Hi Jiri Slaby, On 2024-04-05 at 08:08:23 +0200, Jiri Slaby (SUSE) wrote: > Switch from struct circ_buf to proper kfifo. kfifo provides much better > API, esp. when wrap-around of the buffer needs to be taken into account. > Look at pl011_dma_tx_refill() or cpm_uart_tx_pump() changes for example. > > Kfifo API can also fill in scatter-gather DMA structures, so it easier > for that use case too. Look at lpuart_dma_tx() for example. Note that > not all drivers can be converted to that (like atmel_serial), they > handle DMA specially. > > Note that usb-serial uses kfifo for TX for ages. > > omap needed a bit more care as it needs to put a char into FIFO to start > the DMA transfer when OMAP_DMA_TX_KICK is set. In that case, we have to > do kfifo_dma_out_prepare twice: once to find out the tx_size (to find > out if it is worths to do DMA at all -- size >= 4), the second time for > the actual transfer. > > All traces of circ_buf are removed from serial_core.h (and its struct > uart_state). > > Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx> > Cc: Al Cooper <alcooperx@xxxxxxxxx> > Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx> > Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> > Cc: Kumaravel Thiagarajan <kumaravel.thiagarajan@xxxxxxxxxxxxx> > Cc: Tharun Kumar P <tharunkumar.pasumarthi@xxxxxxxxxxxxx> > Cc: Russell King <linux@xxxxxxxxxxxxxxx> > Cc: Vineet Gupta <vgupta@xxxxxxxxxx> > Cc: Richard Genoud <richard.genoud@xxxxxxxxx> > Cc: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx> > Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> > Cc: Claudiu Beznea <claudiu.beznea@xxxxxxxxx> > Cc: Alexander Shiyan <shc_work@xxxxxxx> > Cc: Baruch Siach <baruch@xxxxxxxxxx> > Cc: "Maciej W. Rozycki" <macro@xxxxxxxxxxx> > Cc: Shawn Guo <shawnguo@xxxxxxxxxx> > Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > Cc: Fabio Estevam <festevam@xxxxxxxxx> > Cc: Neil Armstrong <neil.armstrong@xxxxxxxxxx> > Cc: Kevin Hilman <khilman@xxxxxxxxxxxx> > Cc: Jerome Brunet <jbrunet@xxxxxxxxxxxx> > Cc: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> > Cc: Taichi Sugaya <sugaya.taichi@xxxxxxxxxxxxx> > Cc: Takao Orito <orito.takao@xxxxxxxxxxxxx> > Cc: Bjorn Andersson <andersson@xxxxxxxxxx> > Cc: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> > Cc: "Pali Rohár" <pali@xxxxxxxxxx> > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > Cc: Nicholas Piggin <npiggin@xxxxxxxxx> > Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxx> > Cc: "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxx> > Cc: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> > Cc: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > Cc: Alim Akhtar <alim.akhtar@xxxxxxxxxxx> > Cc: Laxman Dewangan <ldewangan@xxxxxxxxxx> > Cc: Thierry Reding <thierry.reding@xxxxxxxxx> > Cc: Jonathan Hunter <jonathanh@xxxxxxxxxx> > Cc: Orson Zhai <orsonzhai@xxxxxxxxx> > Cc: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> > Cc: Chunyan Zhang <zhang.lyra@xxxxxxxxx> > Cc: Patrice Chotard <patrice.chotard@xxxxxxxxxxx> > Cc: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx> > Cc: Alexandre Torgue <alexandre.torgue@xxxxxxxxxxx> > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> > Cc: Hammer Hsieh <hammerh0314@xxxxxxxxx> > Cc: Peter Korsgaard <jacmet@xxxxxxxxxx> > Cc: Timur Tabi <timur@xxxxxxxxxx> > Cc: Michal Simek <michal.simek@xxxxxxx> > Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx> > Cc: "Christian König" <christian.koenig@xxxxxxx> > --- > drivers/tty/serial/8250/8250_bcm7271.c | 14 +++--- > drivers/tty/serial/8250/8250_core.c | 3 +- > drivers/tty/serial/8250/8250_dma.c | 23 ++++++---- > drivers/tty/serial/8250/8250_exar.c | 5 ++- > drivers/tty/serial/8250/8250_mtk.c | 2 +- > drivers/tty/serial/8250/8250_omap.c | 47 +++++++++++++------- > drivers/tty/serial/8250/8250_pci1xxxx.c | 50 ++++++++++------------ > drivers/tty/serial/8250/8250_port.c | 22 ++++++---- > drivers/tty/serial/amba-pl011.c | 46 +++++++++----------- > drivers/tty/serial/ar933x_uart.c | 15 +++---- > drivers/tty/serial/arc_uart.c | 8 ++-- > drivers/tty/serial/atmel_serial.c | 57 +++++++++++++------------ > drivers/tty/serial/clps711x.c | 12 +++--- > drivers/tty/serial/cpm_uart.c | 20 +++------ > drivers/tty/serial/digicolor-usart.c | 12 +++--- > drivers/tty/serial/dz.c | 13 +++--- > drivers/tty/serial/fsl_linflexuart.c | 17 ++++---- > drivers/tty/serial/fsl_lpuart.c | 39 ++++++++--------- > drivers/tty/serial/icom.c | 25 +++-------- > drivers/tty/serial/imx.c | 54 ++++++++++------------- > drivers/tty/serial/ip22zilog.c | 26 ++++++----- > drivers/tty/serial/jsm/jsm_cls.c | 29 ++++--------- > drivers/tty/serial/jsm/jsm_neo.c | 38 ++++++----------- > drivers/tty/serial/max3100.c | 14 +++--- > drivers/tty/serial/max310x.c | 35 +++++++-------- > drivers/tty/serial/men_z135_uart.c | 26 +++++------ > drivers/tty/serial/meson_uart.c | 11 +++-- > drivers/tty/serial/milbeaut_usio.c | 15 ++++--- > drivers/tty/serial/msm_serial.c | 30 ++++++------- > drivers/tty/serial/mvebu-uart.c | 8 ++-- > drivers/tty/serial/mxs-auart.c | 23 +++------- > drivers/tty/serial/pch_uart.c | 21 +++++---- > drivers/tty/serial/pic32_uart.c | 15 +++---- > drivers/tty/serial/pmac_zilog.c | 24 +++++------ > drivers/tty/serial/qcom_geni_serial.c | 36 ++++++++-------- > drivers/tty/serial/rda-uart.c | 17 +++----- > drivers/tty/serial/samsung_tty.c | 54 ++++++++++++----------- > drivers/tty/serial/sb1250-duart.c | 13 +++--- > drivers/tty/serial/sc16is7xx.c | 40 +++++++---------- > drivers/tty/serial/sccnxp.c | 16 ++++--- > drivers/tty/serial/serial-tegra.c | 43 ++++++++++--------- > drivers/tty/serial/serial_core.c | 56 +++++++++--------------- > drivers/tty/serial/serial_port.c | 2 +- > drivers/tty/serial/sh-sci.c | 51 +++++++++++----------- > drivers/tty/serial/sprd_serial.c | 20 ++++----- > drivers/tty/serial/st-asc.c | 4 +- > drivers/tty/serial/stm32-usart.c | 52 +++++++++------------- > drivers/tty/serial/sunhv.c | 35 ++++++++------- > drivers/tty/serial/sunplus-uart.c | 16 ++++--- > drivers/tty/serial/sunsab.c | 30 +++++++------ > drivers/tty/serial/sunsu.c | 15 ++++--- > drivers/tty/serial/sunzilog.c | 27 ++++++------ > drivers/tty/serial/tegra-tcu.c | 10 +++-- > drivers/tty/serial/timbuart.c | 17 +++----- > drivers/tty/serial/uartlite.c | 13 +++--- > drivers/tty/serial/ucc_uart.c | 20 +++------ > drivers/tty/serial/xilinx_uartps.c | 20 ++++----- > drivers/tty/serial/zs.c | 13 +++--- > include/linux/serial_core.h | 49 +++++++++++++-------- > 59 files changed, 688 insertions(+), 780 deletions(-) > Greeting! I used syzkaller and Internal v6.9-rc4 kernel which include Linux next kernel, and found deadlock in console_flush_all issue, bisected the commit is: " 1788cf6a91d9 tty: serial: switch from circ_buf to kfifo " All info: https://github.com/xupengfe/syzkaller_logs/tree/main/240415_195447_console_flush_all Syzkaller reproduced code: https://github.com/xupengfe/syzkaller_logs/blob/main/240415_195447_console_flush_all/repro.c Syzkaller syscall repro steps: https://github.com/xupengfe/syzkaller_logs/blob/main/240415_195447_console_flush_all/repro.prog Syzkaller report: https://github.com/xupengfe/syzkaller_logs/blob/main/240415_195447_console_flush_all/repro.report Bisect info: https://github.com/xupengfe/syzkaller_logs/blob/main/240415_195447_console_flush_all/bisect_info.log Kconfig(make olddefconfig): https://github.com/xupengfe/syzkaller_logs/blob/main/240415_195447_console_flush_all/kconfig_origin Issue dmesg: https://github.com/xupengfe/syzkaller_logs/blob/main/240415_195447_console_flush_all/df0b4fecf9eb384062e52e3b572ee8c431afc63b_dmesg.log Issue bzImage: https://github.com/xupengfe/syzkaller_logs/raw/main/240415_195447_console_flush_all/bzImage_df0b4fecf_v6.9-rc4_next.tar.gz [ 17.841572] ------------[ cut here ]------------ [ 17.841624] [ 17.841628] ====================================================== [ 17.841631] WARNING: possible circular locking dependency detected [ 17.841632] 6.9.0-rc4-df0b4fecf9eb+ #1 Not tainted [ 17.841636] ------------------------------------------------------ [ 17.841638] repro/726 is trying to acquire lock: [ 17.841641] ffffffff86d6da80 (console_owner){....}-{0:0}, at: console_flush_all+0x51a/0xc40 [ 17.841665] [ 17.841665] but task is already holding lock: [ 17.841667] ffffffff89aa52b8 (&port_lock_key){-...}-{2:2}, at: uart_put_char+0x118/0x510 [ 17.841684] [ 17.841684] which lock already depends on the new lock. [ 17.841684] [ 17.841686] [ 17.841686] the existing dependency chain (in reverse order) is: [ 17.841687] [ 17.841687] -> #1 (&port_lock_key){-...}-{2:2}: [ 17.841695] _raw_spin_lock_irqsave+0x52/0x80 [ 17.841707] serial8250_console_write+0xad4/0x10a0 [ 17.841715] univ8250_console_write+0x6f/0x90 [ 17.841723] console_flush_all+0x55c/0xc40 [ 17.841730] console_unlock+0xb6/0x240 [ 17.841738] vprintk_emit+0x2d0/0x680 [ 17.841745] vprintk_default+0x2f/0x40 [ 17.841752] vprintk+0xd0/0x170 [ 17.841758] _printk+0xc4/0x100 [ 17.841764] register_console+0xcb4/0x13e0 [ 17.841771] univ8250_console_init+0x41/0x60 [ 17.841783] console_init+0xae/0x5a0 [ 17.841793] start_kernel+0x275/0x510 [ 17.841799] x86_64_start_reservations+0x1c/0x30 [ 17.841807] x86_64_start_kernel+0xa0/0xb0 [ 17.841815] common_startup_64+0x13e/0x141 [ 17.841826] [ 17.841826] -> #0 (console_owner){....}-{0:0}: [ 17.841833] __lock_acquire+0x2fc1/0x5ca0 [ 17.841843] lock_acquire+0x1c8/0x550 [ 17.841850] console_flush_all+0x52f/0xc40 [ 17.841857] console_unlock+0xb6/0x240 [ 17.841864] vprintk_emit+0x2d0/0x680 [ 17.841870] vprintk_default+0x2f/0x40 [ 17.841877] vprintk+0xd0/0x170 [ 17.841884] _printk+0xc4/0x100 [ 17.841889] report_bug+0x26a/0x4b0 [ 17.841897] handle_bug+0xa2/0x130 [ 17.841905] exc_invalid_op+0x3c/0x80 [ 17.841912] asm_exc_invalid_op+0x1f/0x30 [ 17.841923] uart_put_char+0x3ac/0x510 [ 17.841929] tty_put_char+0xce/0x170 [ 17.841937] do_output_char+0x164/0x890 [ 17.841947] __process_echoes+0x225/0xb30 [ 17.841954] n_tty_receive_buf_common+0x4cb/0x16c0 [ 17.841960] n_tty_receive_buf+0x3a/0x50 [ 17.841966] tty_ioctl+0x529/0x1740 [ 17.841973] __x64_sys_ioctl+0x1b9/0x230 [ 17.841983] x64_sys_call+0x120d/0x20c0 [ 17.841990] do_syscall_64+0x6f/0x150 [ 17.841996] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 17.842004] [ 17.842004] other info that might help us debug this: [ 17.842004] [ 17.842005] Possible unsafe locking scenario: [ 17.842005] [ 17.842007] CPU0 CPU1 [ 17.842008] ---- ---- [ 17.842009] lock(&port_lock_key); [ 17.842013] lock(console_owner); [ 17.842016] lock(&port_lock_key); [ 17.842020] lock(console_owner); [ 17.842023] [ 17.842023] *** DEADLOCK *** [ 17.842023] [ 17.842024] 7 locks held by repro/726: [ 17.842028] #0: ffff888018b120a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3f/0x50 [ 17.842042] #1: ffff88800c6d0ca0 (&buf->lock){+.+.}-{3:3}, at: tty_buffer_lock_exclusive+0x39/0x50 [ 17.842059] #2: ffff888018b122e8 (&tty->termios_rwsem){++++}-{3:3}, at: n_tty_receive_buf_common+0x97/0x16c0 [ 17.842074] #3: ffffc90000bd2380 (&ldata->output_lock){+.+.}-{3:3}, at: n_tty_receive_buf_common+0x495/0x16c0 [ 17.842088] #4: ffffffff89aa52b8 (&port_lock_key){-...}-{2:2}, at: uart_put_char+0x118/0x510 [ 17.842103] #5: ffffffff86e4e0e0 (console_lock){+.+.}-{0:0}, at: vprintk_default+0x2f/0x40 [ 17.842118] #6: ffffffff86e4e150 (console_srcu){....}-{0:0}, at: console_flush_all+0x14d/0xc40 [ 17.842133] [ 17.842133] stack backtrace: [ 17.842136] CPU: 0 PID: 726 Comm: repro Not tainted 6.9.0-rc4-df0b4fecf9eb+ #1 [ 17.842143] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 [ 17.842146] Call Trace: [ 17.842150] <TASK> [ 17.842153] dump_stack_lvl+0xea/0x150 [ 17.842162] dump_stack+0x19/0x20 [ 17.842168] print_circular_bug+0x477/0x740 [ 17.842179] check_noncircular+0x2f4/0x3e0 [ 17.842189] ? __pfx_check_noncircular+0x10/0x10 [ 17.842200] ? lockdep_lock+0xd0/0x1d0 [ 17.842207] ? __pfx_lockdep_lock+0x10/0x10 [ 17.842217] __lock_acquire+0x2fc1/0x5ca0 [ 17.842232] ? __pfx___lock_acquire+0x10/0x10 [ 17.842243] lock_acquire+0x1c8/0x550 [ 17.842252] ? console_flush_all+0x51a/0xc40 [ 17.842261] ? __pfx_lock_acquire+0x10/0x10 [ 17.842269] ? __pfx_lock_release+0x10/0x10 [ 17.842278] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 17.842289] console_flush_all+0x52f/0xc40 [ 17.842296] ? console_flush_all+0x51a/0xc40 [ 17.842307] ? __pfx_console_flush_all+0x10/0x10 [ 17.842316] ? lock_acquire+0x1d8/0x550 [ 17.842326] console_unlock+0xb6/0x240 [ 17.842334] ? __pfx_console_unlock+0x10/0x10 [ 17.842342] ? do_raw_spin_unlock+0x15c/0x210 [ 17.842349] ? _raw_spin_unlock_irqrestore+0x45/0x70 [ 17.842357] ? vprintk_default+0x2f/0x40 [ 17.842366] vprintk_emit+0x2d0/0x680 [ 17.842377] vprintk_default+0x2f/0x40 [ 17.842385] vprintk+0xd0/0x170 [ 17.842394] _printk+0xc4/0x100 [ 17.842400] ? __pfx__printk+0x10/0x10 [ 17.842408] ? __pfx___lock_acquire+0x10/0x10 [ 17.842417] ? lockdep_unlock+0xf5/0x250 [ 17.842424] ? report_bug+0x25e/0x4b0 [ 17.842430] ? report_bug+0x253/0x4b0 [ 17.842437] ? uart_put_char+0x3ac/0x510 [ 17.842444] report_bug+0x26a/0x4b0 [ 17.842451] ? uart_put_char+0x3ac/0x510 [ 17.842461] handle_bug+0xa2/0x130 [ 17.842469] exc_invalid_op+0x3c/0x80 [ 17.842479] asm_exc_invalid_op+0x1f/0x30 [ 17.842487] RIP: 0010:uart_put_char+0x3ac/0x510 [ 17.842495] Code: 49 8b bc 24 08 01 00 00 31 c9 ba 01 00 00 00 be 03 00 00 00 48 81 c7 a0 03 00 00 e8 ce 78 e4 fd e9 63 ff ff ff e8 44 b8 0b fe <0f> 0b e8 3d b8 0b fe 4d 8d ac 24 08 01 00 00 4c 89 f6 4c 89 e7 e8 [ 17.842502] RSP: 0018:ffff888010ec7a40 EFLAGS: 00010093 [ 17.842509] RAX: 0000000000000000 RBX: ffff88800c6d0be8 RCX: ffffffff81420511 [ 17.842514] RDX: ffff88801cd8ca00 RSI: ffffffff83590dec RDI: ffff88800c6d0f48 [ 17.842518] RBP: ffff888010ec7a80 R08: 0000000000000001 R09: ffffed10021d8f34 [ 17.842522] R10: 0000000000000003 R11: 0000000000000001 R12: ffffffff89aa52a0 [ 17.842527] R13: ffff88800c6d0f84 R14: 0000000000000293 R15: ffffffff83590a40 [ 17.842532] ? __pfx_uart_put_char+0x10/0x10 [ 17.842542] ? do_raw_spin_lock+0x141/0x280 [ 17.842549] ? uart_put_char+0x3ac/0x510 [ 17.842560] ? __pfx_uart_put_char+0x10/0x10 [ 17.842567] tty_put_char+0xce/0x170 [ 17.842574] ? __pfx_tty_put_char+0x10/0x10 [ 17.842581] ? _raw_spin_unlock_irqrestore+0x35/0x70 [ 17.842589] ? lockdep_hardirqs_on+0x89/0x110 [ 17.842599] do_output_char+0x164/0x890 [ 17.842609] __process_echoes+0x225/0xb30 [ 17.842622] n_tty_receive_buf_common+0x4cb/0x16c0 [ 17.842629] ? __pfx___mutex_lock+0x10/0x10 [ 17.842643] ? __pfx_n_tty_receive_buf+0x10/0x10 [ 17.842650] n_tty_receive_buf+0x3a/0x50 [ 17.842658] tty_ioctl+0x529/0x1740 [ 17.842667] ? __pfx_tty_ioctl+0x10/0x10 [ 17.842674] ? lock_release+0x415/0x800 [ 17.842683] ? __pfx_lock_release+0x10/0x10 [ 17.842694] ? __this_cpu_preempt_check+0x21/0x30 [ 17.842703] ? seqcount_lockdep_reader_access.constprop.0+0xb4/0xd0 [ 17.842715] ? lockdep_hardirqs_on+0x89/0x110 [ 17.842723] ? trace_hardirqs_on+0x51/0x60 [ 17.842732] ? seqcount_lockdep_reader_access.constprop.0+0xc0/0xd0 [ 17.842741] ? __sanitizer_cov_trace_cmp4+0x1a/0x20 [ 17.842751] ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20 [ 17.842759] ? security_file_ioctl+0x9d/0xd0 [ 17.842771] ? __pfx_tty_ioctl+0x10/0x10 [ 17.842781] __x64_sys_ioctl+0x1b9/0x230 [ 17.842793] x64_sys_call+0x120d/0x20c0 [ 17.842799] do_syscall_64+0x6f/0x150 [ 17.842807] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 17.842817] RIP: 0033:0x7f53ca43ee5d [ 17.842823] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 93 af 1b 00 f7 d8 64 89 01 48 [ 17.842829] RSP: 002b:00007ffce9c89108 EFLAGS: 00000213 ORIG_RAX: 0000000000000010 [ 17.842835] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f53ca43ee5d [ 17.842839] RDX: 0000000020000000 RSI: 0000000000005412 RDI: 0000000000000003 [ 17.842843] RBP: 00007ffce9c89120 R08: 0000000000000800 R09: 0000000000000800 [ 17.842849] R10: 0000000000000000 R11: 0000000000000213 R12: 00007ffce9c89238 [ 17.842853] R13: 0000000000401136 R14: 0000000000403e08 R15: 00007f53ca71e000 [ 17.842863] </TASK> [ 17.879899] WARNING: CPU: 0 PID: 726 at drivers/tty/serial/serial_core.c:561 uart_put_char+0x3ac/0x510 [ 17.880328] Modules linked in: [ 17.880477] CPU: 0 PID: 726 Comm: repro Not tainted 6.9.0-rc4-df0b4fecf9eb+ #1 [ 17.880808] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 [ 17.881320] RIP: 0010:uart_put_char+0x3ac/0x510 [ 17.881538] Code: 49 8b bc 24 08 01 00 00 31 c9 ba 01 00 00 00 be 03 00 00 00 48 81 c7 a0 03 00 00 e8 ce 78 e4 fd e9 63 ff ff ff e8 44 b8 0b fe <0f> 0b e8 3d b8 0b fe 4d 8d ac 24 08 01 00 00 4c 89 f6 4c 89 e7 e8 [ 17.882367] RSP: 0018:ffff888010ec7a40 EFLAGS: 00010093 [ 17.882610] RAX: 0000000000000000 RBX: ffff88800c6d0be8 RCX: ffffffff81420511 [ 17.882935] RDX: ffff88801cd8ca00 RSI: ffffffff83590dec RDI: ffff88800c6d0f48 [ 17.883260] RBP: ffff888010ec7a80 R08: 0000000000000001 R09: ffffed10021d8f34 [ 17.883588] R10: 0000000000000003 R11: 0000000000000001 R12: ffffffff89aa52a0 [ 17.883913] R13: ffff88800c6d0f84 R14: 0000000000000293 R15: ffffffff83590a40 [ 17.884239] FS: 00007f53ca6d7600(0000) GS:ffff88806ca00000(0000) knlGS:0000000000000000 [ 17.884606] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 17.884872] CR2: 0000000020000040 CR3: 00000000118de000 CR4: 0000000000750ef0 [ 17.885198] PKRU: 55555554 [ 17.885329] Call Trace: [ 17.885448] <TASK> [ 17.885554] ? show_regs+0xa8/0xc0 [ 17.885724] ? __warn+0xee/0x380 [ 17.885888] ? report_bug+0x25e/0x4b0 [ 17.886064] ? uart_put_char+0x3ac/0x510 [ 17.886254] ? report_bug+0x2cb/0x4b0 [ 17.886431] ? uart_put_char+0x3ac/0x510 [ 17.886622] ? handle_bug+0xa2/0x130 [ 17.886798] ? exc_invalid_op+0x3c/0x80 [ 17.886985] ? asm_exc_invalid_op+0x1f/0x30 [ 17.887186] ? __pfx_uart_put_char+0x10/0x10 [ 17.887397] ? do_raw_spin_lock+0x141/0x280 [ 17.887604] ? uart_put_char+0x3ac/0x510 [ 17.887795] ? uart_put_char+0x3ac/0x510 [ 17.887987] ? __pfx_uart_put_char+0x10/0x10 [ 17.888193] tty_put_char+0xce/0x170 [ 17.888367] ? __pfx_tty_put_char+0x10/0x10 [ 17.888566] ? _raw_spin_unlock_irqrestore+0x35/0x70 [ 17.888801] ? lockdep_hardirqs_on+0x89/0x110 [ 17.889014] do_output_char+0x164/0x890 [ 17.889203] __process_echoes+0x225/0xb30 [ 17.889403] n_tty_receive_buf_common+0x4cb/0x16c0 [ 17.889629] ? __pfx___mutex_lock+0x10/0x10 [ 17.889836] ? __pfx_n_tty_receive_buf+0x10/0x10 [ 17.890055] n_tty_receive_buf+0x3a/0x50 [ 17.890244] tty_ioctl+0x529/0x1740 [ 17.890417] ? __pfx_tty_ioctl+0x10/0x10 [ 17.890608] ? lock_release+0x415/0x800 [ 17.890797] ? __pfx_lock_release+0x10/0x10 [ 17.891002] ? __this_cpu_preempt_check+0x21/0x30 [ 17.891227] ? seqcount_lockdep_reader_access.constprop.0+0xb4/0xd0 [ 17.891526] ? lockdep_hardirqs_on+0x89/0x110 [ 17.891737] ? trace_hardirqs_on+0x51/0x60 [ 17.891933] ? seqcount_lockdep_reader_access.constprop.0+0xc0/0xd0 [ 17.892227] ? __sanitizer_cov_trace_cmp4+0x1a/0x20 [ 17.892460] ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20 [ 17.892715] ? security_file_ioctl+0x9d/0xd0 [ 17.892921] ? __pfx_tty_ioctl+0x10/0x10 [ 17.893111] __x64_sys_ioctl+0x1b9/0x230 [ 17.893303] x64_sys_call+0x120d/0x20c0 [ 17.893487] do_syscall_64+0x6f/0x150 [ 17.893664] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 17.893904] RIP: 0033:0x7f53ca43ee5d [ 17.894075] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 93 af 1b 00 f7 d8 64 89 01 48 [ 17.894904] RSP: 002b:00007ffce9c89108 EFLAGS: 00000213 ORIG_RAX: 0000000000000010 [ 17.895249] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f53ca43ee5d [ 17.895578] RDX: 0000000020000000 RSI: 0000000000005412 RDI: 0000000000000003 [ 17.895903] RBP: 00007ffce9c89120 R08: 0000000000000800 R09: 0000000000000800 [ 17.896229] R10: 0000000000000000 R11: 0000000000000213 R12: 00007ffce9c89238 [ 17.896553] R13: 0000000000401136 R14: 0000000000403e08 R15: 00007f53ca71e000 [ 17.896884] </TASK> [ 17.896993] irq event stamp: 3868 [ 17.897152] hardirqs last enabled at (3867): [<ffffffff856c5e05>] _raw_spin_unlock_irqrestore+0x35/0x70 [ 17.897582] hardirqs last disabled at (3868): [<ffffffff856c5ab0>] _raw_spin_lock_irqsave+0x70/0x80 [ 17.897994] softirqs last enabled at (1736): [<ffffffff811172dd>] fpu_flush_thread+0x2fd/0x3e0 [ 17.898396] softirqs last disabled at (1734): [<ffffffff8111721e>] fpu_flush_thread+0x23e/0x3e0 [ 17.898797] ---[ end trace 0000000000000000 ]--- Hope reproduced code and bisection is helpful. --- If you don't need the following environment to reproduce the problem or if you already have one reproduced environment, please ignore the following information. How to reproduce: git clone https://gitlab.com/xupengfe/repro_vm_env.git cd repro_vm_env tar -xvf repro_vm_env.tar.gz cd repro_vm_env; ./start3.sh // it needs qemu-system-x86_64 and I used v7.1.0 // start3.sh will load bzImage_2241ab53cbb5cdb08a6b2d4688feb13971058f65 v6.2-rc5 kernel // You could change the bzImage_xxx as you want // Maybe you need to remove line "-drive if=pflash,format=raw,readonly=on,file=./OVMF_CODE.fd \" for different qemu version You could use below command to log in, there is no password for root. ssh -p 10023 root@localhost After login vm(virtual machine) successfully, you could transfer reproduced binary to the vm by below way, and reproduce the problem in vm: gcc -pthread -o repro repro.c scp -P 10023 repro root@localhost:/root/ Get the bzImage for target kernel: Please use target kconfig and copy it to kernel_src/.config make olddefconfig make -jx bzImage //x should equal or less than cpu num your pc has Fill the bzImage file into above start3.sh to load the target kernel in vm. Tips: If you already have qemu-system-x86_64, please ignore below info. If you want to install qemu v7.1.0 version: git clone https://github.com/qemu/qemu.git cd qemu git checkout -f v7.1.0 mkdir build cd build yum install -y ninja-build.x86_64 yum -y install libslirp-devel.x86_64 ../configure --target-list=x86_64-softmmu --enable-kvm --enable-vnc --enable-gtk --enable-sdl --enable-usb-redir --enable-slirp make make install Best Regards, Thanks! > diff --git a/drivers/tty/serial/8250/8250_bcm7271.c b/drivers/tty/serial/8250/8250_bcm7271.c > index 5daa38d9c64e..de270863eb5e 100644 > --- a/drivers/tty/serial/8250/8250_bcm7271.c > +++ b/drivers/tty/serial/8250/8250_bcm7271.c > @@ -413,20 +413,18 @@ static int stop_tx_dma(struct uart_8250_port *p) > static int brcmuart_tx_dma(struct uart_8250_port *p) > { > struct brcmuart_priv *priv = p->port.private_data; > - struct circ_buf *xmit = &p->port.state->xmit; > + struct tty_port *tport = &p->port.state->port; > u32 tx_size; > > if (uart_tx_stopped(&p->port) || priv->tx_running || > - uart_circ_empty(xmit)) { > + kfifo_is_empty(&tport->xmit_fifo)) { > return 0; > } > - tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > > priv->dma.tx_err = 0; > - memcpy(priv->tx_buf, &xmit->buf[xmit->tail], tx_size); > - uart_xmit_advance(&p->port, tx_size); > + tx_size = uart_fifo_out(&p->port, priv->tx_buf, UART_XMIT_SIZE); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&p->port); > > udma_writel(priv, REGS_DMA_TX, UDMA_TX_TRANSFER_LEN, tx_size); > @@ -540,7 +538,7 @@ static void brcmuart_tx_isr(struct uart_port *up, u32 isr) > struct brcmuart_priv *priv = up->private_data; > struct device *dev = up->dev; > struct uart_8250_port *port_8250 = up_to_u8250p(up); > - struct circ_buf *xmit = &port_8250->port.state->xmit; > + struct tty_port *tport = &port_8250->port.state->port; > > if (isr & UDMA_INTR_TX_ABORT) { > if (priv->tx_running) > @@ -548,7 +546,7 @@ static void brcmuart_tx_isr(struct uart_port *up, u32 isr) > return; > } > priv->tx_running = false; > - if (!uart_circ_empty(xmit) && !uart_tx_stopped(up)) > + if (!kfifo_is_empty(&tport->xmit_fifo) && !uart_tx_stopped(up)) > brcmuart_tx_dma(port_8250); > } > > diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c > index b62ad9006780..3a1936b7f05f 100644 > --- a/drivers/tty/serial/8250/8250_core.c > +++ b/drivers/tty/serial/8250/8250_core.c > @@ -280,7 +280,8 @@ static void serial8250_backup_timeout(struct timer_list *t) > */ > lsr = serial_lsr_in(up); > if ((iir & UART_IIR_NO_INT) && (up->ier & UART_IER_THRI) && > - (!uart_circ_empty(&up->port.state->xmit) || up->port.x_char) && > + (!kfifo_is_empty(&up->port.state->port.xmit_fifo) || > + up->port.x_char) && > (lsr & UART_LSR_THRE)) { > iir &= ~(UART_IIR_ID | UART_IIR_NO_INT); > iir |= UART_IIR_THRI; > diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c > index 8b2c3f478b17..8a353e3cc3dd 100644 > --- a/drivers/tty/serial/8250/8250_dma.c > +++ b/drivers/tty/serial/8250/8250_dma.c > @@ -15,7 +15,7 @@ static void __dma_tx_complete(void *param) > { > struct uart_8250_port *p = param; > struct uart_8250_dma *dma = p->dma; > - struct circ_buf *xmit = &p->port.state->xmit; > + struct tty_port *tport = &p->port.state->port; > unsigned long flags; > int ret; > > @@ -28,7 +28,7 @@ static void __dma_tx_complete(void *param) > > uart_xmit_advance(&p->port, dma->tx_size); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&p->port); > > ret = serial8250_tx_dma(p); > @@ -86,7 +86,7 @@ static void dma_rx_complete(void *param) > int serial8250_tx_dma(struct uart_8250_port *p) > { > struct uart_8250_dma *dma = p->dma; > - struct circ_buf *xmit = &p->port.state->xmit; > + struct tty_port *tport = &p->port.state->port; > struct dma_async_tx_descriptor *desc; > struct uart_port *up = &p->port; > struct scatterlist sg; > @@ -103,18 +103,23 @@ int serial8250_tx_dma(struct uart_8250_port *p) > uart_xchar_out(up, UART_TX); > } > > - if (uart_tx_stopped(&p->port) || uart_circ_empty(xmit)) { > + if (uart_tx_stopped(&p->port) || kfifo_is_empty(&tport->xmit_fifo)) { > /* We have been called from __dma_tx_complete() */ > return 0; > } > > - dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > - > serial8250_do_prepare_tx_dma(p); > > sg_init_table(&sg, 1); > - sg_dma_address(&sg) = dma->tx_addr + xmit->tail; > - sg_dma_len(&sg) = dma->tx_size; > + /* kfifo can do more than one sg, we don't (quite yet) */ > + ret = kfifo_dma_out_prepare_mapped(&tport->xmit_fifo, &sg, 1, > + UART_XMIT_SIZE, dma->tx_addr); > + > + /* we already checked empty fifo above, so there should be something */ > + if (WARN_ON_ONCE(ret != 1)) > + return 0; > + > + dma->tx_size = sg_dma_len(&sg); > > desc = dmaengine_prep_slave_sg(dma->txchan, &sg, 1, > DMA_MEM_TO_DEV, > @@ -257,7 +262,7 @@ int serial8250_request_dma(struct uart_8250_port *p) > > /* TX buffer */ > dma->tx_addr = dma_map_single(dma->txchan->device->dev, > - p->port.state->xmit.buf, > + p->port.state->port.xmit_buf, > UART_XMIT_SIZE, > DMA_TO_DEVICE); > if (dma_mapping_error(dma->txchan->device->dev, dma->tx_addr)) { > diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c > index 0440df7de1ed..f89dabfc0f97 100644 > --- a/drivers/tty/serial/8250/8250_exar.c > +++ b/drivers/tty/serial/8250/8250_exar.c > @@ -214,7 +214,7 @@ static void exar_shutdown(struct uart_port *port) > { > bool tx_complete = false; > struct uart_8250_port *up = up_to_u8250p(port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > int i = 0; > u16 lsr; > > @@ -225,7 +225,8 @@ static void exar_shutdown(struct uart_port *port) > else > tx_complete = false; > usleep_range(1000, 1100); > - } while (!uart_circ_empty(xmit) && !tx_complete && i++ < 1000); > + } while (!kfifo_is_empty(&tport->xmit_fifo) && > + !tx_complete && i++ < 1000); > > serial8250_do_shutdown(port); > } > diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c > index 9ff6bbe9c086..c365a349421a 100644 > --- a/drivers/tty/serial/8250/8250_mtk.c > +++ b/drivers/tty/serial/8250/8250_mtk.c > @@ -199,7 +199,7 @@ static int mtk8250_startup(struct uart_port *port) > > if (up->dma) { > data->rx_status = DMA_RX_START; > - uart_circ_clear(&port->state->xmit); > + kfifo_reset(&port->state->port.xmit_fifo); > } > #endif > memset(&port->icount, 0, sizeof(port->icount)); > diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c > index 879e77b30701..c07d924d5add 100644 > --- a/drivers/tty/serial/8250/8250_omap.c > +++ b/drivers/tty/serial/8250/8250_omap.c > @@ -1094,7 +1094,7 @@ static void omap_8250_dma_tx_complete(void *param) > { > struct uart_8250_port *p = param; > struct uart_8250_dma *dma = p->dma; > - struct circ_buf *xmit = &p->port.state->xmit; > + struct tty_port *tport = &p->port.state->port; > unsigned long flags; > bool en_thri = false; > struct omap8250_priv *priv = p->port.private_data; > @@ -1113,10 +1113,10 @@ static void omap_8250_dma_tx_complete(void *param) > omap8250_restore_regs(p); > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&p->port); > > - if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) { > + if (!kfifo_is_empty(&tport->xmit_fifo) && !uart_tx_stopped(&p->port)) { > int ret; > > ret = omap_8250_tx_dma(p); > @@ -1138,15 +1138,15 @@ static int omap_8250_tx_dma(struct uart_8250_port *p) > { > struct uart_8250_dma *dma = p->dma; > struct omap8250_priv *priv = p->port.private_data; > - struct circ_buf *xmit = &p->port.state->xmit; > + struct tty_port *tport = &p->port.state->port; > struct dma_async_tx_descriptor *desc; > struct scatterlist sg; > - unsigned int skip_byte = 0; > + int skip_byte = -1; > int ret; > > if (dma->tx_running) > return 0; > - if (uart_tx_stopped(&p->port) || uart_circ_empty(xmit)) { > + if (uart_tx_stopped(&p->port) || kfifo_is_empty(&tport->xmit_fifo)) { > > /* > * Even if no data, we need to return an error for the two cases > @@ -1161,8 +1161,18 @@ static int omap_8250_tx_dma(struct uart_8250_port *p) > return 0; > } > > - dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + sg_init_table(&sg, 1); > + ret = kfifo_dma_out_prepare_mapped(&tport->xmit_fifo, &sg, 1, > + UART_XMIT_SIZE, dma->tx_addr); > + if (ret != 1) { > + serial8250_clear_THRI(p); > + return 0; > + } > + > + dma->tx_size = sg_dma_len(&sg); > + > if (priv->habit & OMAP_DMA_TX_KICK) { > + unsigned char c; > u8 tx_lvl; > > /* > @@ -1189,13 +1199,16 @@ static int omap_8250_tx_dma(struct uart_8250_port *p) > ret = -EINVAL; > goto err; > } > - skip_byte = 1; > + if (!kfifo_get(&tport->xmit_fifo, &c)) { > + ret = -EINVAL; > + goto err; > + } > + skip_byte = c; > + /* now we need to recompute due to kfifo_get */ > + kfifo_dma_out_prepare_mapped(&tport->xmit_fifo, &sg, 1, > + UART_XMIT_SIZE, dma->tx_addr); > } > > - sg_init_table(&sg, 1); > - sg_dma_address(&sg) = dma->tx_addr + xmit->tail + skip_byte; > - sg_dma_len(&sg) = dma->tx_size - skip_byte; > - > desc = dmaengine_prep_slave_sg(dma->txchan, &sg, 1, DMA_MEM_TO_DEV, > DMA_PREP_INTERRUPT | DMA_CTRL_ACK); > if (!desc) { > @@ -1218,11 +1231,13 @@ static int omap_8250_tx_dma(struct uart_8250_port *p) > dma->tx_err = 0; > > serial8250_clear_THRI(p); > - if (skip_byte) > - serial_out(p, UART_TX, xmit->buf[xmit->tail]); > - return 0; > + ret = 0; > + goto out_skip; > err: > dma->tx_err = 1; > +out_skip: > + if (skip_byte >= 0) > + serial_out(p, UART_TX, skip_byte); > return ret; > } > > @@ -1311,7 +1326,7 @@ static int omap_8250_dma_handle_irq(struct uart_port *port) > serial8250_modem_status(up); > if (status & UART_LSR_THRE && up->dma->tx_err) { > if (uart_tx_stopped(&up->port) || > - uart_circ_empty(&up->port.state->xmit)) { > + kfifo_is_empty(&up->port.state->port.xmit_fifo)) { > up->dma->tx_err = 0; > serial8250_tx_chars(up); > } else { > diff --git a/drivers/tty/serial/8250/8250_pci1xxxx.c b/drivers/tty/serial/8250/8250_pci1xxxx.c > index 2fbb5851f788..d3930bf32fe4 100644 > --- a/drivers/tty/serial/8250/8250_pci1xxxx.c > +++ b/drivers/tty/serial/8250/8250_pci1xxxx.c > @@ -382,10 +382,10 @@ static void pci1xxxx_rx_burst(struct uart_port *port, u32 uart_status) > } > > static void pci1xxxx_process_write_data(struct uart_port *port, > - struct circ_buf *xmit, > int *data_empty_count, > u32 *valid_byte_count) > { > + struct tty_port *tport = &port->state->port; > u32 valid_burst_count = *valid_byte_count / UART_BURST_SIZE; > > /* > @@ -395,41 +395,36 @@ static void pci1xxxx_process_write_data(struct uart_port *port, > * one byte at a time. > */ > while (valid_burst_count) { > + u32 c; > + > if (*data_empty_count - UART_BURST_SIZE < 0) > break; > - if (xmit->tail > (UART_XMIT_SIZE - UART_BURST_SIZE)) > + if (kfifo_len(&tport->xmit_fifo) < UART_BURST_SIZE) > + break; > + if (WARN_ON(kfifo_out(&tport->xmit_fifo, (u8 *)&c, sizeof(c)) != > + sizeof(c))) > break; > - writel(*(unsigned int *)&xmit->buf[xmit->tail], > - port->membase + UART_TX_BURST_FIFO); > + writel(c, port->membase + UART_TX_BURST_FIFO); > *valid_byte_count -= UART_BURST_SIZE; > *data_empty_count -= UART_BURST_SIZE; > valid_burst_count -= UART_BYTE_SIZE; > - > - xmit->tail = (xmit->tail + UART_BURST_SIZE) & > - (UART_XMIT_SIZE - 1); > } > > while (*valid_byte_count) { > - if (*data_empty_count - UART_BYTE_SIZE < 0) > + u8 c; > + > + if (!kfifo_get(&tport->xmit_fifo, &c)) > break; > - writeb(xmit->buf[xmit->tail], port->membase + > - UART_TX_BYTE_FIFO); > + writeb(c, port->membase + UART_TX_BYTE_FIFO); > *data_empty_count -= UART_BYTE_SIZE; > *valid_byte_count -= UART_BYTE_SIZE; > > - /* > - * When the tail of the circular buffer is reached, the next > - * byte is transferred to the beginning of the buffer. > - */ > - xmit->tail = (xmit->tail + UART_BYTE_SIZE) & > - (UART_XMIT_SIZE - 1); > - > /* > * If there are any pending burst count, data is handled by > * transmitting DWORDs at a time. > */ > - if (valid_burst_count && (xmit->tail < > - (UART_XMIT_SIZE - UART_BURST_SIZE))) > + if (valid_burst_count && > + kfifo_len(&tport->xmit_fifo) >= UART_BURST_SIZE) > break; > } > } > @@ -437,11 +432,9 @@ static void pci1xxxx_process_write_data(struct uart_port *port, > static void pci1xxxx_tx_burst(struct uart_port *port, u32 uart_status) > { > struct uart_8250_port *up = up_to_u8250p(port); > + struct tty_port *tport = &port->state->port; > u32 valid_byte_count; > int data_empty_count; > - struct circ_buf *xmit; > - > - xmit = &port->state->xmit; > > if (port->x_char) { > writeb(port->x_char, port->membase + UART_TX); > @@ -450,25 +443,25 @@ static void pci1xxxx_tx_burst(struct uart_port *port, u32 uart_status) > return; > } > > - if ((uart_tx_stopped(port)) || (uart_circ_empty(xmit))) { > + if ((uart_tx_stopped(port)) || kfifo_is_empty(&tport->xmit_fifo)) { > port->ops->stop_tx(port); > } else { > data_empty_count = (pci1xxxx_read_burst_status(port) & > UART_BST_STAT_TX_COUNT_MASK) >> 8; > do { > - valid_byte_count = uart_circ_chars_pending(xmit); > + valid_byte_count = kfifo_len(&tport->xmit_fifo); > > - pci1xxxx_process_write_data(port, xmit, > + pci1xxxx_process_write_data(port, > &data_empty_count, > &valid_byte_count); > > port->icount.tx++; > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > break; > } while (data_empty_count && valid_byte_count); > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > /* > @@ -476,7 +469,8 @@ static void pci1xxxx_tx_burst(struct uart_port *port, u32 uart_status) > * the HW can go idle. So we get here once again with empty FIFO and > * disable the interrupt and RPM in __stop_tx() > */ > - if (uart_circ_empty(xmit) && !(up->capabilities & UART_CAP_RPM)) > + if (kfifo_is_empty(&tport->xmit_fifo) && > + !(up->capabilities & UART_CAP_RPM)) > port->ops->stop_tx(port); > } > > diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c > index fc9dd5d45295..0c19451d0332 100644 > --- a/drivers/tty/serial/8250/8250_port.c > +++ b/drivers/tty/serial/8250/8250_port.c > @@ -1630,7 +1630,7 @@ static void serial8250_start_tx(struct uart_port *port) > /* Port locked to synchronize UART_IER access against the console. */ > lockdep_assert_held_once(&port->lock); > > - if (!port->x_char && uart_circ_empty(&port->state->xmit)) > + if (!port->x_char && kfifo_is_empty(&port->state->port.xmit_fifo)) > return; > > serial8250_rpm_get_tx(up); > @@ -1778,7 +1778,7 @@ EXPORT_SYMBOL_GPL(serial8250_rx_chars); > void serial8250_tx_chars(struct uart_8250_port *up) > { > struct uart_port *port = &up->port; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > int count; > > if (port->x_char) { > @@ -1789,14 +1789,19 @@ void serial8250_tx_chars(struct uart_8250_port *up) > serial8250_stop_tx(port); > return; > } > - if (uart_circ_empty(xmit)) { > + if (kfifo_is_empty(&tport->xmit_fifo)) { > __stop_tx(up); > return; > } > > count = up->tx_loadsz; > do { > - serial_out(up, UART_TX, xmit->buf[xmit->tail]); > + unsigned char c; > + > + if (!uart_fifo_get(port, &c)) > + break; > + > + serial_out(up, UART_TX, c); > if (up->bugs & UART_BUG_TXRACE) { > /* > * The Aspeed BMC virtual UARTs have a bug where data > @@ -1809,9 +1814,7 @@ void serial8250_tx_chars(struct uart_8250_port *up) > */ > serial_in(up, UART_SCR); > } > - uart_xmit_advance(port, 1); > - if (uart_circ_empty(xmit)) > - break; > + > if ((up->capabilities & UART_CAP_HFIFO) && > !uart_lsr_tx_empty(serial_in(up, UART_LSR))) > break; > @@ -1821,7 +1824,7 @@ void serial8250_tx_chars(struct uart_8250_port *up) > break; > } while (--count > 0); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > /* > @@ -1829,7 +1832,8 @@ void serial8250_tx_chars(struct uart_8250_port *up) > * HW can go idle. So we get here once again with empty FIFO and disable > * the interrupt and RPM in __stop_tx() > */ > - if (uart_circ_empty(xmit) && !(up->capabilities & UART_CAP_RPM)) > + if (kfifo_is_empty(&tport->xmit_fifo) && > + !(up->capabilities & UART_CAP_RPM)) > __stop_tx(up); > } > EXPORT_SYMBOL_GPL(serial8250_tx_chars); > diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c > index 2fa3fb30dc6c..51b202eb8296 100644 > --- a/drivers/tty/serial/amba-pl011.c > +++ b/drivers/tty/serial/amba-pl011.c > @@ -535,6 +535,7 @@ static void pl011_start_tx_pio(struct uart_amba_port *uap); > static void pl011_dma_tx_callback(void *data) > { > struct uart_amba_port *uap = data; > + struct tty_port *tport = &uap->port.state->port; > struct pl011_dmatx_data *dmatx = &uap->dmatx; > unsigned long flags; > u16 dmacr; > @@ -558,7 +559,7 @@ static void pl011_dma_tx_callback(void *data) > * get further refills (hence we check dmacr). > */ > if (!(dmacr & UART011_TXDMAE) || uart_tx_stopped(&uap->port) || > - uart_circ_empty(&uap->port.state->xmit)) { > + kfifo_is_empty(&tport->xmit_fifo)) { > uap->dmatx.queued = false; > uart_port_unlock_irqrestore(&uap->port, flags); > return; > @@ -588,7 +589,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap) > struct dma_chan *chan = dmatx->chan; > struct dma_device *dma_dev = chan->device; > struct dma_async_tx_descriptor *desc; > - struct circ_buf *xmit = &uap->port.state->xmit; > + struct tty_port *tport = &uap->port.state->port; > unsigned int count; > > /* > @@ -597,7 +598,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap) > * the standard interrupt handling. This ensures that we > * issue a uart_write_wakeup() at the appropriate time. > */ > - count = uart_circ_chars_pending(xmit); > + count = kfifo_len(&tport->xmit_fifo); > if (count < (uap->fifosize >> 1)) { > uap->dmatx.queued = false; > return 0; > @@ -613,21 +614,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap) > if (count > PL011_DMA_BUFFER_SIZE) > count = PL011_DMA_BUFFER_SIZE; > > - if (xmit->tail < xmit->head) { > - memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], count); > - } else { > - size_t first = UART_XMIT_SIZE - xmit->tail; > - size_t second; > - > - if (first > count) > - first = count; > - second = count - first; > - > - memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], first); > - if (second) > - memcpy(&dmatx->buf[first], &xmit->buf[0], second); > - } > - > + count = kfifo_out_peek(&tport->xmit_fifo, dmatx->buf, count); > dmatx->len = count; > dmatx->dma = dma_map_single(dma_dev->dev, dmatx->buf, count, > DMA_TO_DEVICE); > @@ -670,7 +657,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap) > */ > uart_xmit_advance(&uap->port, count); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&uap->port); > > return 1; > @@ -1454,7 +1441,7 @@ static bool pl011_tx_char(struct uart_amba_port *uap, unsigned char c, > /* Returns true if tx interrupts have to be (kept) enabled */ > static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) > { > - struct circ_buf *xmit = &uap->port.state->xmit; > + struct tty_port *tport = &uap->port.state->port; > int count = uap->fifosize >> 1; > > if (uap->port.x_char) { > @@ -1463,7 +1450,7 @@ static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) > uap->port.x_char = 0; > --count; > } > - if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(&uap->port)) { > pl011_stop_tx(&uap->port); > return false; > } > @@ -1472,20 +1459,25 @@ static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) > if (pl011_dma_tx_irq(uap)) > return true; > > - do { > + while (1) { > + unsigned char c; > + > if (likely(from_irq) && count-- == 0) > break; > > - if (!pl011_tx_char(uap, xmit->buf[xmit->tail], from_irq)) > + if (!kfifo_peek(&tport->xmit_fifo, &c)) > + break; > + > + if (!pl011_tx_char(uap, c, from_irq)) > break; > > - xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); > - } while (!uart_circ_empty(xmit)); > + kfifo_skip(&tport->xmit_fifo); > + } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&uap->port); > > - if (uart_circ_empty(xmit)) { > + if (kfifo_is_empty(&tport->xmit_fifo)) { > pl011_stop_tx(&uap->port); > return false; > } > diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c > index 7790cbc57391..f2836ecc5c19 100644 > --- a/drivers/tty/serial/ar933x_uart.c > +++ b/drivers/tty/serial/ar933x_uart.c > @@ -390,7 +390,7 @@ static void ar933x_uart_rx_chars(struct ar933x_uart_port *up) > > static void ar933x_uart_tx_chars(struct ar933x_uart_port *up) > { > - struct circ_buf *xmit = &up->port.state->xmit; > + struct tty_port *tport = &up->port.state->port; > struct serial_rs485 *rs485conf = &up->port.rs485; > int count; > bool half_duplex_send = false; > @@ -399,7 +399,7 @@ static void ar933x_uart_tx_chars(struct ar933x_uart_port *up) > return; > > if ((rs485conf->flags & SER_RS485_ENABLED) && > - (up->port.x_char || !uart_circ_empty(xmit))) { > + (up->port.x_char || !kfifo_is_empty(&tport->xmit_fifo))) { > ar933x_uart_stop_rx_interrupt(up); > gpiod_set_value(up->rts_gpiod, !!(rs485conf->flags & SER_RS485_RTS_ON_SEND)); > half_duplex_send = true; > @@ -408,6 +408,7 @@ static void ar933x_uart_tx_chars(struct ar933x_uart_port *up) > count = up->port.fifosize; > do { > unsigned int rdata; > + unsigned char c; > > rdata = ar933x_uart_read(up, AR933X_UART_DATA_REG); > if ((rdata & AR933X_UART_DATA_TX_CSR) == 0) > @@ -420,18 +421,16 @@ static void ar933x_uart_tx_chars(struct ar933x_uart_port *up) > continue; > } > > - if (uart_circ_empty(xmit)) > + if (!uart_fifo_get(&up->port, &c)) > break; > > - ar933x_uart_putc(up, xmit->buf[xmit->tail]); > - > - uart_xmit_advance(&up->port, 1); > + ar933x_uart_putc(up, c); > } while (--count > 0); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&up->port); > > - if (!uart_circ_empty(xmit)) { > + if (!kfifo_is_empty(&tport->xmit_fifo)) { > ar933x_uart_start_tx_interrupt(up); > } else if (half_duplex_send) { > ar933x_uart_wait_tx_complete(up); > diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c > index 1aa5b2b49c26..5c4895d154c0 100644 > --- a/drivers/tty/serial/arc_uart.c > +++ b/drivers/tty/serial/arc_uart.c > @@ -155,7 +155,7 @@ static unsigned int arc_serial_tx_empty(struct uart_port *port) > */ > static void arc_serial_tx_chars(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > int sent = 0; > unsigned char ch; > > @@ -164,9 +164,7 @@ static void arc_serial_tx_chars(struct uart_port *port) > port->icount.tx++; > port->x_char = 0; > sent = 1; > - } else if (!uart_circ_empty(xmit)) { > - ch = xmit->buf[xmit->tail]; > - uart_xmit_advance(port, 1); > + } else if (uart_fifo_get(port, &ch)) { > while (!(UART_GET_STATUS(port) & TXEMPTY)) > cpu_relax(); > UART_SET_DATA(port, ch); > @@ -177,7 +175,7 @@ static void arc_serial_tx_chars(struct uart_port *port) > * If num chars in xmit buffer are too few, ask tty layer for more. > * By Hard ISR to schedule processing in software interrupt part > */ > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > if (sent) > diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c > index 85667f709515..5bb5e4303754 100644 > --- a/drivers/tty/serial/atmel_serial.c > +++ b/drivers/tty/serial/atmel_serial.c > @@ -857,7 +857,7 @@ static void atmel_complete_tx_dma(void *arg) > { > struct atmel_uart_port *atmel_port = arg; > struct uart_port *port = &atmel_port->uart; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > struct dma_chan *chan = atmel_port->chan_tx; > unsigned long flags; > > @@ -873,15 +873,15 @@ static void atmel_complete_tx_dma(void *arg) > atmel_port->desc_tx = NULL; > spin_unlock(&atmel_port->lock_tx); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > /* > - * xmit is a circular buffer so, if we have just send data from > - * xmit->tail to the end of xmit->buf, now we have to transmit the > - * remaining data from the beginning of xmit->buf to xmit->head. > + * xmit is a circular buffer so, if we have just send data from the > + * tail to the end, now we have to transmit the remaining data from the > + * beginning to the head. > */ > - if (!uart_circ_empty(xmit)) > + if (!kfifo_is_empty(&tport->xmit_fifo)) > atmel_tasklet_schedule(atmel_port, &atmel_port->tasklet_tx); > else if (atmel_uart_is_half_duplex(port)) { > /* > @@ -919,18 +919,18 @@ static void atmel_release_tx_dma(struct uart_port *port) > static void atmel_tx_dma(struct uart_port *port) > { > struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > struct dma_chan *chan = atmel_port->chan_tx; > struct dma_async_tx_descriptor *desc; > struct scatterlist sgl[2], *sg, *sg_tx = &atmel_port->sg_tx; > - unsigned int tx_len, part1_len, part2_len, sg_len; > + unsigned int tx_len, tail, part1_len, part2_len, sg_len; > dma_addr_t phys_addr; > > /* Make sure we have an idle channel */ > if (atmel_port->desc_tx != NULL) > return; > > - if (!uart_circ_empty(xmit) && !uart_tx_stopped(port)) { > + if (!kfifo_is_empty(&tport->xmit_fifo) && !uart_tx_stopped(port)) { > /* > * DMA is idle now. > * Port xmit buffer is already mapped, > @@ -940,9 +940,8 @@ static void atmel_tx_dma(struct uart_port *port) > * Take the port lock to get a > * consistent xmit buffer state. > */ > - tx_len = CIRC_CNT_TO_END(xmit->head, > - xmit->tail, > - UART_XMIT_SIZE); > + tx_len = kfifo_out_linear(&tport->xmit_fifo, &tail, > + UART_XMIT_SIZE); > > if (atmel_port->fifo_size) { > /* multi data mode */ > @@ -956,7 +955,7 @@ static void atmel_tx_dma(struct uart_port *port) > > sg_init_table(sgl, 2); > sg_len = 0; > - phys_addr = sg_dma_address(sg_tx) + xmit->tail; > + phys_addr = sg_dma_address(sg_tx) + tail; > if (part1_len) { > sg = &sgl[sg_len++]; > sg_dma_address(sg) = phys_addr; > @@ -973,7 +972,7 @@ static void atmel_tx_dma(struct uart_port *port) > > /* > * save tx_len so atmel_complete_tx_dma() will increase > - * xmit->tail correctly > + * tail correctly > */ > atmel_port->tx_len = tx_len; > > @@ -1003,13 +1002,14 @@ static void atmel_tx_dma(struct uart_port *port) > dma_async_issue_pending(chan); > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > } > > static int atmel_prepare_tx_dma(struct uart_port *port) > { > struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); > + struct tty_port *tport = &port->state->port; > struct device *mfd_dev = port->dev->parent; > dma_cap_mask_t mask; > struct dma_slave_config config; > @@ -1031,11 +1031,11 @@ static int atmel_prepare_tx_dma(struct uart_port *port) > spin_lock_init(&atmel_port->lock_tx); > sg_init_table(&atmel_port->sg_tx, 1); > /* UART circular tx buffer is an aligned page. */ > - BUG_ON(!PAGE_ALIGNED(port->state->xmit.buf)); > + BUG_ON(!PAGE_ALIGNED(tport->xmit_buf)); > sg_set_page(&atmel_port->sg_tx, > - virt_to_page(port->state->xmit.buf), > + virt_to_page(tport->xmit_buf), > UART_XMIT_SIZE, > - offset_in_page(port->state->xmit.buf)); > + offset_in_page(tport->xmit_buf)); > nent = dma_map_sg(port->dev, > &atmel_port->sg_tx, > 1, > @@ -1047,7 +1047,7 @@ static int atmel_prepare_tx_dma(struct uart_port *port) > } else { > dev_dbg(port->dev, "%s: mapped %d@%p to %pad\n", __func__, > sg_dma_len(&atmel_port->sg_tx), > - port->state->xmit.buf, > + tport->xmit_buf, > &sg_dma_address(&atmel_port->sg_tx)); > } > > @@ -1459,9 +1459,8 @@ static void atmel_release_tx_pdc(struct uart_port *port) > static void atmel_tx_pdc(struct uart_port *port) > { > struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx; > - int count; > > /* nothing left to transmit? */ > if (atmel_uart_readl(port, ATMEL_PDC_TCR)) > @@ -1474,17 +1473,19 @@ static void atmel_tx_pdc(struct uart_port *port) > /* disable PDC transmit */ > atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS); > > - if (!uart_circ_empty(xmit) && !uart_tx_stopped(port)) { > + if (!kfifo_is_empty(&tport->xmit_fifo) && !uart_tx_stopped(port)) { > + unsigned int count, tail; > + > dma_sync_single_for_device(port->dev, > pdc->dma_addr, > pdc->dma_size, > DMA_TO_DEVICE); > > - count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + count = kfifo_out_linear(&tport->xmit_fifo, &tail, > + UART_XMIT_SIZE); > pdc->ofs = count; > > - atmel_uart_writel(port, ATMEL_PDC_TPR, > - pdc->dma_addr + xmit->tail); > + atmel_uart_writel(port, ATMEL_PDC_TPR, pdc->dma_addr + tail); > atmel_uart_writel(port, ATMEL_PDC_TCR, count); > /* re-enable PDC transmit */ > atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN); > @@ -1498,7 +1499,7 @@ static void atmel_tx_pdc(struct uart_port *port) > } > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > } > > @@ -1506,9 +1507,9 @@ static int atmel_prepare_tx_pdc(struct uart_port *port) > { > struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); > struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > - pdc->buf = xmit->buf; > + pdc->buf = tport->xmit_buf; > pdc->dma_addr = dma_map_single(port->dev, > pdc->buf, > UART_XMIT_SIZE, > diff --git a/drivers/tty/serial/clps711x.c b/drivers/tty/serial/clps711x.c > index 7927725b8957..30425a3d19fb 100644 > --- a/drivers/tty/serial/clps711x.c > +++ b/drivers/tty/serial/clps711x.c > @@ -146,7 +146,8 @@ static irqreturn_t uart_clps711x_int_tx(int irq, void *dev_id) > { > struct uart_port *port = dev_id; > struct clps711x_port *s = dev_get_drvdata(port->dev); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > + unsigned char c; > > if (port->x_char) { > writew(port->x_char, port->membase + UARTDR_OFFSET); > @@ -155,7 +156,7 @@ static irqreturn_t uart_clps711x_int_tx(int irq, void *dev_id) > return IRQ_HANDLED; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > if (s->tx_enabled) { > disable_irq_nosync(port->irq); > s->tx_enabled = 0; > @@ -163,18 +164,17 @@ static irqreturn_t uart_clps711x_int_tx(int irq, void *dev_id) > return IRQ_HANDLED; > } > > - while (!uart_circ_empty(xmit)) { > + while (uart_fifo_get(port, &c)) { > u32 sysflg = 0; > > - writew(xmit->buf[xmit->tail], port->membase + UARTDR_OFFSET); > - uart_xmit_advance(port, 1); > + writew(c, port->membase + UARTDR_OFFSET); > > regmap_read(s->syscon, SYSFLG_OFFSET, &sysflg); > if (sysflg & SYSFLG_UTXFF) > break; > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > return IRQ_HANDLED; > diff --git a/drivers/tty/serial/cpm_uart.c b/drivers/tty/serial/cpm_uart.c > index df56c6c5afd0..a927478f581d 100644 > --- a/drivers/tty/serial/cpm_uart.c > +++ b/drivers/tty/serial/cpm_uart.c > @@ -648,7 +648,7 @@ static int cpm_uart_tx_pump(struct uart_port *port) > int count; > struct uart_cpm_port *pinfo = > container_of(port, struct uart_cpm_port, port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > /* Handle xon/xoff */ > if (port->x_char) { > @@ -673,7 +673,7 @@ static int cpm_uart_tx_pump(struct uart_port *port) > return 1; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > cpm_uart_stop_tx(port); > return 0; > } > @@ -681,16 +681,10 @@ static int cpm_uart_tx_pump(struct uart_port *port) > /* Pick next descriptor and fill from buffer */ > bdp = pinfo->tx_cur; > > - while (!(in_be16(&bdp->cbd_sc) & BD_SC_READY) && !uart_circ_empty(xmit)) { > - count = 0; > + while (!(in_be16(&bdp->cbd_sc) & BD_SC_READY) && > + !kfifo_is_empty(&tport->xmit_fifo)) { > p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo); > - while (count < pinfo->tx_fifosize) { > - *p++ = xmit->buf[xmit->tail]; > - uart_xmit_advance(port, 1); > - count++; > - if (uart_circ_empty(xmit)) > - break; > - } > + count = uart_fifo_out(port, p, pinfo->tx_fifosize); > out_be16(&bdp->cbd_datlen, count); > setbits16(&bdp->cbd_sc, BD_SC_READY); > /* Get next BD. */ > @@ -701,10 +695,10 @@ static int cpm_uart_tx_pump(struct uart_port *port) > } > pinfo->tx_cur = bdp; > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit)) { > + if (kfifo_is_empty(&tport->xmit_fifo)) { > cpm_uart_stop_tx(port); > return 0; > } > diff --git a/drivers/tty/serial/digicolor-usart.c b/drivers/tty/serial/digicolor-usart.c > index e419c4bde8b7..2ccd13cc0a89 100644 > --- a/drivers/tty/serial/digicolor-usart.c > +++ b/drivers/tty/serial/digicolor-usart.c > @@ -179,8 +179,9 @@ static void digicolor_uart_rx(struct uart_port *port) > > static void digicolor_uart_tx(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > unsigned long flags; > + unsigned char c; > > if (digicolor_uart_tx_full(port)) > return; > @@ -194,20 +195,19 @@ static void digicolor_uart_tx(struct uart_port *port) > goto out; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > digicolor_uart_stop_tx(port); > goto out; > } > > - while (!uart_circ_empty(xmit)) { > - writeb(xmit->buf[xmit->tail], port->membase + UA_EMI_REC); > - uart_xmit_advance(port, 1); > + while (uart_fifo_get(port, &c)) { > + writeb(c, port->membase + UA_EMI_REC); > > if (digicolor_uart_tx_full(port)) > break; > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > out: > diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c > index 6df7af9edc1c..eba91daedef8 100644 > --- a/drivers/tty/serial/dz.c > +++ b/drivers/tty/serial/dz.c > @@ -252,13 +252,13 @@ static inline void dz_receive_chars(struct dz_mux *mux) > static inline void dz_transmit_chars(struct dz_mux *mux) > { > struct dz_port *dport = &mux->dport[0]; > - struct circ_buf *xmit; > + struct tty_port *tport; > unsigned char tmp; > u16 status; > > status = dz_in(dport, DZ_CSR); > dport = &mux->dport[LINE(status)]; > - xmit = &dport->port.state->xmit; > + tport = &dport->port.state->port; > > if (dport->port.x_char) { /* XON/XOFF chars */ > dz_out(dport, DZ_TDR, dport->port.x_char); > @@ -267,7 +267,8 @@ static inline void dz_transmit_chars(struct dz_mux *mux) > return; > } > /* If nothing to do or stopped or hardware stopped. */ > - if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) { > + if (uart_tx_stopped(&dport->port) || > + !uart_fifo_get(&dport->port, &tmp)) { > uart_port_lock(&dport->port); > dz_stop_tx(&dport->port); > uart_port_unlock(&dport->port); > @@ -278,15 +279,13 @@ static inline void dz_transmit_chars(struct dz_mux *mux) > * If something to do... (remember the dz has no output fifo, > * so we go one char at a time) :-< > */ > - tmp = xmit->buf[xmit->tail]; > dz_out(dport, DZ_TDR, tmp); > - uart_xmit_advance(&dport->port, 1); > > - if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < DZ_WAKEUP_CHARS) > uart_write_wakeup(&dport->port); > > /* Are we are done. */ > - if (uart_circ_empty(xmit)) { > + if (kfifo_is_empty(&tport->xmit_fifo)) { > uart_port_lock(&dport->port); > dz_stop_tx(&dport->port); > uart_port_unlock(&dport->port); > diff --git a/drivers/tty/serial/fsl_linflexuart.c b/drivers/tty/serial/fsl_linflexuart.c > index 5426322b5f0c..e972df4b188d 100644 > --- a/drivers/tty/serial/fsl_linflexuart.c > +++ b/drivers/tty/serial/fsl_linflexuart.c > @@ -174,17 +174,18 @@ static void linflex_put_char(struct uart_port *sport, unsigned char c) > > static inline void linflex_transmit_buffer(struct uart_port *sport) > { > - struct circ_buf *xmit = &sport->state->xmit; > + struct tty_port *tport = &sport->state->port; > + unsigned char c; > > - while (!uart_circ_empty(xmit)) { > - linflex_put_char(sport, xmit->buf[xmit->tail]); > - uart_xmit_advance(sport, 1); > + while (uart_fifo_get(sport, &c)) { > + linflex_put_char(sport, c); > + sport->icount.tx++; > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(sport); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > linflex_stop_tx(sport); > } > > @@ -200,7 +201,7 @@ static void linflex_start_tx(struct uart_port *port) > static irqreturn_t linflex_txint(int irq, void *dev_id) > { > struct uart_port *sport = dev_id; > - struct circ_buf *xmit = &sport->state->xmit; > + struct tty_port *tport = &sport->state->port; > unsigned long flags; > > uart_port_lock_irqsave(sport, &flags); > @@ -210,7 +211,7 @@ static irqreturn_t linflex_txint(int irq, void *dev_id) > goto out; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(sport)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(sport)) { > linflex_stop_tx(sport); > goto out; > } > diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c > index bbcbc91482af..ae5e1ecc48fc 100644 > --- a/drivers/tty/serial/fsl_lpuart.c > +++ b/drivers/tty/serial/fsl_lpuart.c > @@ -7,6 +7,7 @@ > > #include <linux/bitfield.h> > #include <linux/bits.h> > +#include <linux/circ_buf.h> > #include <linux/clk.h> > #include <linux/console.h> > #include <linux/delay.h> > @@ -473,7 +474,7 @@ static void lpuart32_stop_rx(struct uart_port *port) > > static void lpuart_dma_tx(struct lpuart_port *sport) > { > - struct circ_buf *xmit = &sport->port.state->xmit; > + struct tty_port *tport = &sport->port.state->port; > struct scatterlist *sgl = sport->tx_sgl; > struct device *dev = sport->port.dev; > struct dma_chan *chan = sport->dma_tx_chan; > @@ -482,18 +483,10 @@ static void lpuart_dma_tx(struct lpuart_port *sport) > if (sport->dma_tx_in_progress) > return; > > - sport->dma_tx_bytes = uart_circ_chars_pending(xmit); > - > - if (xmit->tail < xmit->head || xmit->head == 0) { > - sport->dma_tx_nents = 1; > - sg_init_one(sgl, xmit->buf + xmit->tail, sport->dma_tx_bytes); > - } else { > - sport->dma_tx_nents = 2; > - sg_init_table(sgl, 2); > - sg_set_buf(sgl, xmit->buf + xmit->tail, > - UART_XMIT_SIZE - xmit->tail); > - sg_set_buf(sgl + 1, xmit->buf, xmit->head); > - } > + sg_init_table(sgl, ARRAY_SIZE(sport->tx_sgl)); > + sport->dma_tx_bytes = kfifo_len(&tport->xmit_fifo); > + sport->dma_tx_nents = kfifo_dma_out_prepare(&tport->xmit_fifo, sgl, > + ARRAY_SIZE(sport->tx_sgl), sport->dma_tx_bytes); > > ret = dma_map_sg(chan->device->dev, sgl, sport->dma_tx_nents, > DMA_TO_DEVICE); > @@ -521,14 +514,15 @@ static void lpuart_dma_tx(struct lpuart_port *sport) > > static bool lpuart_stopped_or_empty(struct uart_port *port) > { > - return uart_circ_empty(&port->state->xmit) || uart_tx_stopped(port); > + return kfifo_is_empty(&port->state->port.xmit_fifo) || > + uart_tx_stopped(port); > } > > static void lpuart_dma_tx_complete(void *arg) > { > struct lpuart_port *sport = arg; > struct scatterlist *sgl = &sport->tx_sgl[0]; > - struct circ_buf *xmit = &sport->port.state->xmit; > + struct tty_port *tport = &sport->port.state->port; > struct dma_chan *chan = sport->dma_tx_chan; > unsigned long flags; > > @@ -545,7 +539,7 @@ static void lpuart_dma_tx_complete(void *arg) > sport->dma_tx_in_progress = false; > uart_port_unlock_irqrestore(&sport->port, flags); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&sport->port); > > if (waitqueue_active(&sport->dma_wait)) { > @@ -756,8 +750,9 @@ static inline void lpuart_transmit_buffer(struct lpuart_port *sport) > > static inline void lpuart32_transmit_buffer(struct lpuart_port *sport) > { > - struct circ_buf *xmit = &sport->port.state->xmit; > + struct tty_port *tport = &sport->port.state->port; > unsigned long txcnt; > + unsigned char c; > > if (sport->port.x_char) { > lpuart32_write(&sport->port, sport->port.x_char, UARTDATA); > @@ -774,18 +769,18 @@ static inline void lpuart32_transmit_buffer(struct lpuart_port *sport) > txcnt = lpuart32_read(&sport->port, UARTWATER); > txcnt = txcnt >> UARTWATER_TXCNT_OFF; > txcnt &= UARTWATER_COUNT_MASK; > - while (!uart_circ_empty(xmit) && (txcnt < sport->txfifo_size)) { > - lpuart32_write(&sport->port, xmit->buf[xmit->tail], UARTDATA); > - uart_xmit_advance(&sport->port, 1); > + while (txcnt < sport->txfifo_size && > + uart_fifo_get(&sport->port, &c)) { > + lpuart32_write(&sport->port, c, UARTDATA); > txcnt = lpuart32_read(&sport->port, UARTWATER); > txcnt = txcnt >> UARTWATER_TXCNT_OFF; > txcnt &= UARTWATER_COUNT_MASK; > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&sport->port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > lpuart32_stop_tx(&sport->port); > } > > diff --git a/drivers/tty/serial/icom.c b/drivers/tty/serial/icom.c > index a75eafbcbea3..29e42831df39 100644 > --- a/drivers/tty/serial/icom.c > +++ b/drivers/tty/serial/icom.c > @@ -877,10 +877,10 @@ static void shutdown(struct icom_port *icom_port) > static int icom_write(struct uart_port *port) > { > struct icom_port *icom_port = to_icom_port(port); > + struct tty_port *tport = &port->state->port; > unsigned long data_count; > unsigned char cmdReg; > unsigned long offset; > - int temp_tail = port->state->xmit.tail; > > trace(icom_port, "WRITE", 0); > > @@ -890,16 +890,8 @@ static int icom_write(struct uart_port *port) > return 0; > } > > - data_count = 0; > - while ((port->state->xmit.head != temp_tail) && > - (data_count <= XMIT_BUFF_SZ)) { > - > - icom_port->xmit_buf[data_count++] = > - port->state->xmit.buf[temp_tail]; > - > - temp_tail++; > - temp_tail &= (UART_XMIT_SIZE - 1); > - } > + data_count = kfifo_out_peek(&tport->xmit_fifo, icom_port->xmit_buf, > + XMIT_BUFF_SZ); > > if (data_count) { > icom_port->statStg->xmit[0].flags = > @@ -956,7 +948,8 @@ static inline void check_modem_status(struct icom_port *icom_port) > > static void xmit_interrupt(u16 port_int_reg, struct icom_port *icom_port) > { > - u16 count, i; > + struct tty_port *tport = &icom_port->uart_port.state->port; > + u16 count; > > if (port_int_reg & (INT_XMIT_COMPLETED)) { > trace(icom_port, "XMIT_COMPLETE", 0); > @@ -968,13 +961,7 @@ static void xmit_interrupt(u16 port_int_reg, struct icom_port *icom_port) > count = le16_to_cpu(icom_port->statStg->xmit[0].leLength); > icom_port->uart_port.icount.tx += count; > > - for (i=0; i<count && > - !uart_circ_empty(&icom_port->uart_port.state->xmit); i++) { > - > - icom_port->uart_port.state->xmit.tail++; > - icom_port->uart_port.state->xmit.tail &= > - (UART_XMIT_SIZE - 1); > - } > + kfifo_skip_count(&tport->xmit_fifo, count); > > if (!icom_write(&icom_port->uart_port)) > /* activate write queue */ > diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c > index e14813250616..56b76a221082 100644 > --- a/drivers/tty/serial/imx.c > +++ b/drivers/tty/serial/imx.c > @@ -8,6 +8,7 @@ > * Copyright (C) 2004 Pengutronix > */ > > +#include <linux/circ_buf.h> > #include <linux/module.h> > #include <linux/ioport.h> > #include <linux/init.h> > @@ -521,7 +522,8 @@ static void imx_uart_dma_tx(struct imx_port *sport); > /* called with port.lock taken and irqs off */ > static inline void imx_uart_transmit_buffer(struct imx_port *sport) > { > - struct circ_buf *xmit = &sport->port.state->xmit; > + struct tty_port *tport = &sport->port.state->port; > + unsigned char c; > > if (sport->port.x_char) { > /* Send next char */ > @@ -531,7 +533,8 @@ static inline void imx_uart_transmit_buffer(struct imx_port *sport) > return; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || > + uart_tx_stopped(&sport->port)) { > imx_uart_stop_tx(&sport->port); > return; > } > @@ -555,26 +558,22 @@ static inline void imx_uart_transmit_buffer(struct imx_port *sport) > return; > } > > - while (!uart_circ_empty(xmit) && > - !(imx_uart_readl(sport, imx_uart_uts_reg(sport)) & UTS_TXFULL)) { > - /* send xmit->buf[xmit->tail] > - * out the port here */ > - imx_uart_writel(sport, xmit->buf[xmit->tail], URTX0); > - uart_xmit_advance(&sport->port, 1); > - } > + while (!(imx_uart_readl(sport, imx_uart_uts_reg(sport)) & UTS_TXFULL) && > + uart_fifo_get(&sport->port, &c)) > + imx_uart_writel(sport, c, URTX0); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&sport->port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > imx_uart_stop_tx(&sport->port); > } > > static void imx_uart_dma_tx_callback(void *data) > { > struct imx_port *sport = data; > + struct tty_port *tport = &sport->port.state->port; > struct scatterlist *sgl = &sport->tx_sgl[0]; > - struct circ_buf *xmit = &sport->port.state->xmit; > unsigned long flags; > u32 ucr1; > > @@ -592,10 +591,11 @@ static void imx_uart_dma_tx_callback(void *data) > > sport->dma_is_txing = 0; > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&sport->port); > > - if (!uart_circ_empty(xmit) && !uart_tx_stopped(&sport->port)) > + if (!kfifo_is_empty(&tport->xmit_fifo) && > + !uart_tx_stopped(&sport->port)) > imx_uart_dma_tx(sport); > else if (sport->port.rs485.flags & SER_RS485_ENABLED) { > u32 ucr4 = imx_uart_readl(sport, UCR4); > @@ -609,7 +609,7 @@ static void imx_uart_dma_tx_callback(void *data) > /* called with port.lock taken and irqs off */ > static void imx_uart_dma_tx(struct imx_port *sport) > { > - struct circ_buf *xmit = &sport->port.state->xmit; > + struct tty_port *tport = &sport->port.state->port; > struct scatterlist *sgl = sport->tx_sgl; > struct dma_async_tx_descriptor *desc; > struct dma_chan *chan = sport->dma_chan_tx; > @@ -624,18 +624,10 @@ static void imx_uart_dma_tx(struct imx_port *sport) > ucr4 &= ~UCR4_TCEN; > imx_uart_writel(sport, ucr4, UCR4); > > - sport->tx_bytes = uart_circ_chars_pending(xmit); > - > - if (xmit->tail < xmit->head || xmit->head == 0) { > - sport->dma_tx_nents = 1; > - sg_init_one(sgl, xmit->buf + xmit->tail, sport->tx_bytes); > - } else { > - sport->dma_tx_nents = 2; > - sg_init_table(sgl, 2); > - sg_set_buf(sgl, xmit->buf + xmit->tail, > - UART_XMIT_SIZE - xmit->tail); > - sg_set_buf(sgl + 1, xmit->buf, xmit->head); > - } > + sg_init_table(sgl, ARRAY_SIZE(sport->tx_sgl)); > + sport->tx_bytes = kfifo_len(&tport->xmit_fifo); > + sport->dma_tx_nents = kfifo_dma_out_prepare(&tport->xmit_fifo, sgl, > + ARRAY_SIZE(sport->tx_sgl), sport->tx_bytes); > > ret = dma_map_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE); > if (ret == 0) { > @@ -653,8 +645,7 @@ static void imx_uart_dma_tx(struct imx_port *sport) > desc->callback = imx_uart_dma_tx_callback; > desc->callback_param = sport; > > - dev_dbg(dev, "TX: prepare to send %lu bytes by DMA.\n", > - uart_circ_chars_pending(xmit)); > + dev_dbg(dev, "TX: prepare to send %u bytes by DMA.\n", sport->tx_bytes); > > ucr1 = imx_uart_readl(sport, UCR1); > ucr1 |= UCR1_TXDMAEN; > @@ -671,9 +662,10 @@ static void imx_uart_dma_tx(struct imx_port *sport) > static void imx_uart_start_tx(struct uart_port *port) > { > struct imx_port *sport = (struct imx_port *)port; > + struct tty_port *tport = &sport->port.state->port; > u32 ucr1; > > - if (!sport->port.x_char && uart_circ_empty(&port->state->xmit)) > + if (!sport->port.x_char && kfifo_is_empty(&tport->xmit_fifo)) > return; > > /* > @@ -749,7 +741,7 @@ static void imx_uart_start_tx(struct uart_port *port) > return; > } > > - if (!uart_circ_empty(&port->state->xmit) && > + if (!kfifo_is_empty(&tport->xmit_fifo) && > !uart_tx_stopped(port)) > imx_uart_dma_tx(sport); > return; > diff --git a/drivers/tty/serial/ip22zilog.c b/drivers/tty/serial/ip22zilog.c > index 320b29cd4683..c2cae50f06f3 100644 > --- a/drivers/tty/serial/ip22zilog.c > +++ b/drivers/tty/serial/ip22zilog.c > @@ -355,7 +355,8 @@ static void ip22zilog_status_handle(struct uart_ip22zilog_port *up, > static void ip22zilog_transmit_chars(struct uart_ip22zilog_port *up, > struct zilog_channel *channel) > { > - struct circ_buf *xmit; > + struct tty_port *tport; > + unsigned char c; > > if (ZS_IS_CONS(up)) { > unsigned char status = readb(&channel->control); > @@ -398,20 +399,18 @@ static void ip22zilog_transmit_chars(struct uart_ip22zilog_port *up, > > if (up->port.state == NULL) > goto ack_tx_int; > - xmit = &up->port.state->xmit; > - if (uart_circ_empty(xmit)) > - goto ack_tx_int; > + tport = &up->port.state->port; > if (uart_tx_stopped(&up->port)) > goto ack_tx_int; > + if (!uart_fifo_get(&up->port, &c)) > + goto ack_tx_int; > > up->flags |= IP22ZILOG_FLAG_TX_ACTIVE; > - writeb(xmit->buf[xmit->tail], &channel->data); > + writeb(c, &channel->data); > ZSDELAY(); > ZS_WSYNC(channel); > > - uart_xmit_advance(&up->port, 1); > - > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&up->port); > > return; > @@ -600,17 +599,16 @@ static void ip22zilog_start_tx(struct uart_port *port) > port->icount.tx++; > port->x_char = 0; > } else { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > + unsigned char c; > > - if (uart_circ_empty(xmit)) > + if (!uart_fifo_get(port, &c)) > return; > - writeb(xmit->buf[xmit->tail], &channel->data); > + writeb(c, &channel->data); > ZSDELAY(); > ZS_WSYNC(channel); > > - uart_xmit_advance(port, 1); > - > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&up->port); > } > } > diff --git a/drivers/tty/serial/jsm/jsm_cls.c b/drivers/tty/serial/jsm/jsm_cls.c > index ddbd42c09637..6e40792f92cf 100644 > --- a/drivers/tty/serial/jsm/jsm_cls.c > +++ b/drivers/tty/serial/jsm/jsm_cls.c > @@ -443,20 +443,14 @@ static void cls_copy_data_from_uart_to_queue(struct jsm_channel *ch) > > static void cls_copy_data_from_queue_to_uart(struct jsm_channel *ch) > { > - u16 tail; > + struct tty_port *tport; > int n; > - int qlen; > u32 len_written = 0; > - struct circ_buf *circ; > > if (!ch) > return; > > - circ = &ch->uart_port.state->xmit; > - > - /* No data to write to the UART */ > - if (uart_circ_empty(circ)) > - return; > + tport = &ch->uart_port.state->port; > > /* If port is "stopped", don't send any data to the UART */ > if ((ch->ch_flags & CH_STOP) || (ch->ch_flags & CH_BREAK_SENDING)) > @@ -467,29 +461,22 @@ static void cls_copy_data_from_queue_to_uart(struct jsm_channel *ch) > return; > > n = 32; > + while (n > 0) { > + unsigned char c; > > - /* cache tail of queue */ > - tail = circ->tail & (UART_XMIT_SIZE - 1); > - qlen = uart_circ_chars_pending(circ); > - > - /* Find minimum of the FIFO space, versus queue length */ > - n = min(n, qlen); > + if (!kfifo_get(&tport->xmit_fifo, &c)) > + break; > > - while (n > 0) { > - writeb(circ->buf[tail], &ch->ch_cls_uart->txrx); > - tail = (tail + 1) & (UART_XMIT_SIZE - 1); > + writeb(c, &ch->ch_cls_uart->txrx); > n--; > ch->ch_txcount++; > len_written++; > } > > - /* Update the final tail */ > - circ->tail = tail & (UART_XMIT_SIZE - 1); > - > if (len_written > ch->ch_t_tlevel) > ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); > > - if (uart_circ_empty(circ)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > uart_write_wakeup(&ch->uart_port); > } > > diff --git a/drivers/tty/serial/jsm/jsm_neo.c b/drivers/tty/serial/jsm/jsm_neo.c > index 1fa10f19368f..e8e13bf056e2 100644 > --- a/drivers/tty/serial/jsm/jsm_neo.c > +++ b/drivers/tty/serial/jsm/jsm_neo.c > @@ -474,21 +474,21 @@ static void neo_copy_data_from_uart_to_queue(struct jsm_channel *ch) > > static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch) > { > - u16 head; > - u16 tail; > + struct tty_port *tport; > + unsigned char *tail; > + unsigned char c; > int n; > int s; > int qlen; > u32 len_written = 0; > - struct circ_buf *circ; > > if (!ch) > return; > > - circ = &ch->uart_port.state->xmit; > + tport = &ch->uart_port.state->port; > > /* No data to write to the UART */ > - if (uart_circ_empty(circ)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > return; > > /* If port is "stopped", don't send any data to the UART */ > @@ -504,10 +504,9 @@ static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch) > if (ch->ch_cached_lsr & UART_LSR_THRE) { > ch->ch_cached_lsr &= ~(UART_LSR_THRE); > > - writeb(circ->buf[circ->tail], &ch->ch_neo_uart->txrx); > - jsm_dbg(WRITE, &ch->ch_bd->pci_dev, > - "Tx data: %x\n", circ->buf[circ->tail]); > - circ->tail = (circ->tail + 1) & (UART_XMIT_SIZE - 1); > + WARN_ON_ONCE(!kfifo_get(&tport->xmit_fifo, &c)); > + writeb(c, &ch->ch_neo_uart->txrx); > + jsm_dbg(WRITE, &ch->ch_bd->pci_dev, "Tx data: %x\n", c); > ch->ch_txcount++; > } > return; > @@ -520,38 +519,27 @@ static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch) > return; > > n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel; > - > - /* cache head and tail of queue */ > - head = circ->head & (UART_XMIT_SIZE - 1); > - tail = circ->tail & (UART_XMIT_SIZE - 1); > - qlen = uart_circ_chars_pending(circ); > + qlen = kfifo_len(&tport->xmit_fifo); > > /* Find minimum of the FIFO space, versus queue length */ > n = min(n, qlen); > > while (n > 0) { > - > - s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail; > - s = min(s, n); > - > + s = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, n); > if (s <= 0) > break; > > - memcpy_toio(&ch->ch_neo_uart->txrxburst, circ->buf + tail, s); > - /* Add and flip queue if needed */ > - tail = (tail + s) & (UART_XMIT_SIZE - 1); > + memcpy_toio(&ch->ch_neo_uart->txrxburst, tail, s); > + kfifo_skip_count(&tport->xmit_fifo, s); > n -= s; > ch->ch_txcount += s; > len_written += s; > } > > - /* Update the final tail */ > - circ->tail = tail & (UART_XMIT_SIZE - 1); > - > if (len_written >= ch->ch_t_tlevel) > ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM); > > - if (uart_circ_empty(circ)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > uart_write_wakeup(&ch->uart_port); > } > > diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c > index 5efb2b593be3..b83eee37c17d 100644 > --- a/drivers/tty/serial/max3100.c > +++ b/drivers/tty/serial/max3100.c > @@ -257,10 +257,11 @@ static int max3100_handlerx(struct max3100_port *s, u16 rx) > static void max3100_work(struct work_struct *w) > { > struct max3100_port *s = container_of(w, struct max3100_port, work); > + struct tty_port *tport = &s->port.state->port; > + unsigned char ch; > int rxchars; > u16 tx, rx; > int conf, cconf, crts; > - struct circ_buf *xmit = &s->port.state->xmit; > > dev_dbg(&s->spi->dev, "%s\n", __func__); > > @@ -290,10 +291,9 @@ static void max3100_work(struct work_struct *w) > tx = s->port.x_char; > s->port.icount.tx++; > s->port.x_char = 0; > - } else if (!uart_circ_empty(xmit) && > - !uart_tx_stopped(&s->port)) { > - tx = xmit->buf[xmit->tail]; > - uart_xmit_advance(&s->port, 1); > + } else if (!uart_tx_stopped(&s->port) && > + uart_fifo_get(&s->port, &ch)) { > + tx = ch; > } > if (tx != 0xffff) { > max3100_calc_parity(s, &tx); > @@ -307,13 +307,13 @@ static void max3100_work(struct work_struct *w) > tty_flip_buffer_push(&s->port.state->port); > rxchars = 0; > } > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&s->port); > > } while (!s->force_end_work && > !freezing(current) && > ((rx & MAX3100_R) || > - (!uart_circ_empty(xmit) && > + (!kfifo_is_empty(&tport->xmit_fifo) && > !uart_tx_stopped(&s->port)))); > > if (rxchars > 0) > diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c > index 14dd9cfaa9f7..f0eb96429dae 100644 > --- a/drivers/tty/serial/max310x.c > +++ b/drivers/tty/serial/max310x.c > @@ -747,8 +747,9 @@ static void max310x_handle_rx(struct uart_port *port, unsigned int rxlen) > > static void max310x_handle_tx(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > - unsigned int txlen, to_send, until_end; > + struct tty_port *tport = &port->state->port; > + unsigned int txlen, to_send; > + unsigned char *tail; > > if (unlikely(port->x_char)) { > max310x_port_write(port, MAX310X_THR_REG, port->x_char); > @@ -757,32 +758,26 @@ static void max310x_handle_tx(struct uart_port *port) > return; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) > return; > > - /* Get length of data pending in circular buffer */ > - to_send = uart_circ_chars_pending(xmit); > - until_end = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > - if (likely(to_send)) { > + /* > + * It's a circ buffer -- wrap around. > + * We could do that in one SPI transaction, but meh. > + */ > + while (!kfifo_is_empty(&tport->xmit_fifo)) { > /* Limit to space available in TX FIFO */ > txlen = max310x_port_read(port, MAX310X_TXFIFOLVL_REG); > txlen = port->fifosize - txlen; > - to_send = (to_send > txlen) ? txlen : to_send; > - > - if (until_end < to_send) { > - /* > - * It's a circ buffer -- wrap around. > - * We could do that in one SPI transaction, but meh. > - */ > - max310x_batch_write(port, xmit->buf + xmit->tail, until_end); > - max310x_batch_write(port, xmit->buf, to_send - until_end); > - } else { > - max310x_batch_write(port, xmit->buf + xmit->tail, to_send); > - } > + if (!txlen) > + break; > + > + to_send = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen); > + max310x_batch_write(port, tail, to_send); > uart_xmit_advance(port, to_send); > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > } > > diff --git a/drivers/tty/serial/men_z135_uart.c b/drivers/tty/serial/men_z135_uart.c > index 8048fa542fc4..4bff422bb1bc 100644 > --- a/drivers/tty/serial/men_z135_uart.c > +++ b/drivers/tty/serial/men_z135_uart.c > @@ -293,17 +293,14 @@ static void men_z135_handle_rx(struct men_z135_port *uart) > static void men_z135_handle_tx(struct men_z135_port *uart) > { > struct uart_port *port = &uart->port; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > + unsigned char *tail; > + unsigned int n, txfree; > u32 txc; > u32 wptr; > int qlen; > - int n; > - int txfree; > - int head; > - int tail; > - int s; > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > goto out; > > if (uart_tx_stopped(port)) > @@ -313,7 +310,7 @@ static void men_z135_handle_tx(struct men_z135_port *uart) > goto out; > > /* calculate bytes to copy */ > - qlen = uart_circ_chars_pending(xmit); > + qlen = kfifo_len(&tport->xmit_fifo); > if (qlen <= 0) > goto out; > > @@ -345,21 +342,18 @@ static void men_z135_handle_tx(struct men_z135_port *uart) > if (n <= 0) > goto irq_en; > > - head = xmit->head & (UART_XMIT_SIZE - 1); > - tail = xmit->tail & (UART_XMIT_SIZE - 1); > - > - s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail; > - n = min(n, s); > + n = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, > + min_t(unsigned int, UART_XMIT_SIZE, n)); > + memcpy_toio(port->membase + MEN_Z135_TX_RAM, tail, n); > > - memcpy_toio(port->membase + MEN_Z135_TX_RAM, &xmit->buf[xmit->tail], n); > iowrite32(n & 0x3ff, port->membase + MEN_Z135_TX_CTRL); > uart_xmit_advance(port, n); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > irq_en: > - if (!uart_circ_empty(xmit)) > + if (!kfifo_is_empty(&tport->xmit_fifo)) > men_z135_reg_set(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN); > else > men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN); > diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c > index 6feac459c0cf..4587ed4d4d5d 100644 > --- a/drivers/tty/serial/meson_uart.c > +++ b/drivers/tty/serial/meson_uart.c > @@ -141,8 +141,8 @@ static void meson_uart_shutdown(struct uart_port *port) > > static void meson_uart_start_tx(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > - unsigned int ch; > + struct tty_port *tport = &port->state->port; > + unsigned char ch; > u32 val; > > if (uart_tx_stopped(port)) { > @@ -158,21 +158,20 @@ static void meson_uart_start_tx(struct uart_port *port) > continue; > } > > - if (uart_circ_empty(xmit)) > + if (!uart_fifo_get(port, &ch)) > break; > > - ch = xmit->buf[xmit->tail]; > writel(ch, port->membase + AML_UART_WFIFO); > uart_xmit_advance(port, 1); > } > > - if (!uart_circ_empty(xmit)) { > + if (!kfifo_is_empty(&tport->xmit_fifo)) { > val = readl(port->membase + AML_UART_CONTROL); > val |= AML_UART_TX_INT_EN; > writel(val, port->membase + AML_UART_CONTROL); > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > } > > diff --git a/drivers/tty/serial/milbeaut_usio.c b/drivers/tty/serial/milbeaut_usio.c > index da4c6f7e2a30..fb082ee73d5b 100644 > --- a/drivers/tty/serial/milbeaut_usio.c > +++ b/drivers/tty/serial/milbeaut_usio.c > @@ -72,7 +72,7 @@ static void mlb_usio_stop_tx(struct uart_port *port) > > static void mlb_usio_tx_chars(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > int count; > > writew(readw(port->membase + MLB_USIO_REG_FCR) & ~MLB_USIO_FCR_FTIE, > @@ -87,7 +87,7 @@ static void mlb_usio_tx_chars(struct uart_port *port) > port->x_char = 0; > return; > } > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > mlb_usio_stop_tx(port); > return; > } > @@ -96,12 +96,13 @@ static void mlb_usio_tx_chars(struct uart_port *port) > (readw(port->membase + MLB_USIO_REG_FBYTE) & 0xff); > > do { > - writew(xmit->buf[xmit->tail], port->membase + MLB_USIO_REG_DR); > + unsigned char ch; > > - uart_xmit_advance(port, 1); > - if (uart_circ_empty(xmit)) > + if (!uart_fifo_get(port, &ch)) > break; > > + writew(ch, port->membase + MLB_USIO_REG_DR); > + port->icount.tx++; > } while (--count > 0); > > writew(readw(port->membase + MLB_USIO_REG_FCR) & ~MLB_USIO_FCR_FDRQ, > @@ -110,10 +111,10 @@ static void mlb_usio_tx_chars(struct uart_port *port) > writeb(readb(port->membase + MLB_USIO_REG_SCR) | MLB_USIO_SCR_TBIE, > port->membase + MLB_USIO_REG_SCR); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > mlb_usio_stop_tx(port); > } > > diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c > index 7bf30e632313..ae7a8e3cf467 100644 > --- a/drivers/tty/serial/msm_serial.c > +++ b/drivers/tty/serial/msm_serial.c > @@ -452,7 +452,7 @@ static void msm_complete_tx_dma(void *args) > { > struct msm_port *msm_port = args; > struct uart_port *port = &msm_port->uart; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > struct msm_dma *dma = &msm_port->tx_dma; > struct dma_tx_state state; > unsigned long flags; > @@ -486,7 +486,7 @@ static void msm_complete_tx_dma(void *args) > msm_port->imr |= MSM_UART_IMR_TXLEV; > msm_write(port, msm_port->imr, MSM_UART_IMR); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > msm_handle_tx(port); > @@ -496,14 +496,14 @@ static void msm_complete_tx_dma(void *args) > > static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count) > { > - struct circ_buf *xmit = &msm_port->uart.state->xmit; > struct uart_port *port = &msm_port->uart; > + struct tty_port *tport = &port->state->port; > struct msm_dma *dma = &msm_port->tx_dma; > int ret; > u32 val; > > sg_init_table(&dma->tx_sg, 1); > - sg_set_buf(&dma->tx_sg, &xmit->buf[xmit->tail], count); > + kfifo_dma_out_prepare(&tport->xmit_fifo, &dma->tx_sg, 1, count); > > ret = dma_map_sg(port->dev, &dma->tx_sg, 1, dma->dir); > if (ret) > @@ -843,8 +843,8 @@ static void msm_handle_rx(struct uart_port *port) > > static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count) > { > - struct circ_buf *xmit = &port->state->xmit; > struct msm_port *msm_port = to_msm_port(port); > + struct tty_port *tport = &port->state->port; > unsigned int num_chars; > unsigned int tf_pointer = 0; > void __iomem *tf; > @@ -858,8 +858,7 @@ static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count) > msm_reset_dm_count(port, tx_count); > > while (tf_pointer < tx_count) { > - int i; > - char buf[4] = { 0 }; > + unsigned char buf[4] = { 0 }; > > if (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY)) > break; > @@ -870,26 +869,23 @@ static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count) > else > num_chars = 1; > > - for (i = 0; i < num_chars; i++) > - buf[i] = xmit->buf[xmit->tail + i]; > - > + num_chars = uart_fifo_out(port, buf, num_chars); > iowrite32_rep(tf, buf, 1); > - uart_xmit_advance(port, num_chars); > tf_pointer += num_chars; > } > > /* disable tx interrupts if nothing more to send */ > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > msm_stop_tx(port); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > } > > static void msm_handle_tx(struct uart_port *port) > { > struct msm_port *msm_port = to_msm_port(port); > - struct circ_buf *xmit = &msm_port->uart.state->xmit; > + struct tty_port *tport = &port->state->port; > struct msm_dma *dma = &msm_port->tx_dma; > unsigned int pio_count, dma_count, dma_min; > char buf[4] = { 0 }; > @@ -913,13 +909,13 @@ static void msm_handle_tx(struct uart_port *port) > return; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > msm_stop_tx(port); > return; > } > > - pio_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > - dma_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + dma_count = pio_count = kfifo_out_linear(&tport->xmit_fifo, NULL, > + UART_XMIT_SIZE); > > dma_min = 1; /* Always DMA */ > if (msm_port->is_uartdm > UARTDM_1P3) { > diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c > index 0255646bc175..5de57b77abdb 100644 > --- a/drivers/tty/serial/mvebu-uart.c > +++ b/drivers/tty/serial/mvebu-uart.c > @@ -219,12 +219,10 @@ static void mvebu_uart_stop_tx(struct uart_port *port) > static void mvebu_uart_start_tx(struct uart_port *port) > { > unsigned int ctl; > - struct circ_buf *xmit = &port->state->xmit; > + unsigned char c; > > - if (IS_EXTENDED(port) && !uart_circ_empty(xmit)) { > - writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port)); > - uart_xmit_advance(port, 1); > - } > + if (IS_EXTENDED(port) && uart_fifo_get(port, &c)) > + writel(c, port->membase + UART_TSH(port)); > > ctl = readl(port->membase + UART_INTR(port)); > ctl |= CTRL_TX_RDY_INT(port); > diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c > index 4749331fe618..144b35d31497 100644 > --- a/drivers/tty/serial/mxs-auart.c > +++ b/drivers/tty/serial/mxs-auart.c > @@ -517,7 +517,7 @@ static void mxs_auart_tx_chars(struct mxs_auart_port *s); > static void dma_tx_callback(void *param) > { > struct mxs_auart_port *s = param; > - struct circ_buf *xmit = &s->port.state->xmit; > + struct tty_port *tport = &s->port.state->port; > > dma_unmap_sg(s->dev, &s->tx_sgl, 1, DMA_TO_DEVICE); > > @@ -526,7 +526,7 @@ static void dma_tx_callback(void *param) > smp_mb__after_atomic(); > > /* wake up the possible processes. */ > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&s->port); > > mxs_auart_tx_chars(s); > @@ -568,33 +568,22 @@ static int mxs_auart_dma_tx(struct mxs_auart_port *s, int size) > > static void mxs_auart_tx_chars(struct mxs_auart_port *s) > { > - struct circ_buf *xmit = &s->port.state->xmit; > + struct tty_port *tport = &s->port.state->port; > bool pending; > u8 ch; > > if (auart_dma_enabled(s)) { > u32 i = 0; > - int size; > void *buffer = s->tx_dma_buf; > > if (test_and_set_bit(MXS_AUART_DMA_TX_SYNC, &s->flags)) > return; > > - while (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) { > - size = min_t(u32, UART_XMIT_SIZE - i, > - CIRC_CNT_TO_END(xmit->head, > - xmit->tail, > - UART_XMIT_SIZE)); > - memcpy(buffer + i, xmit->buf + xmit->tail, size); > - xmit->tail = (xmit->tail + size) & (UART_XMIT_SIZE - 1); > - > - i += size; > - if (i >= UART_XMIT_SIZE) > - break; > - } > - > if (uart_tx_stopped(&s->port)) > mxs_auart_stop_tx(&s->port); > + else > + i = kfifo_out(&tport->xmit_fifo, buffer, > + UART_XMIT_SIZE); > > if (i) { > mxs_auart_dma_tx(s, i); > diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c > index 89257cddf540..c7cee5fee603 100644 > --- a/drivers/tty/serial/pch_uart.c > +++ b/drivers/tty/serial/pch_uart.c > @@ -808,7 +808,7 @@ static int dma_handle_rx(struct eg20t_port *priv) > static unsigned int handle_tx(struct eg20t_port *priv) > { > struct uart_port *port = &priv->port; > - struct circ_buf *xmit = &port->state->xmit; > + unsigned char ch; > int fifo_size; > int tx_empty; > > @@ -830,9 +830,9 @@ static unsigned int handle_tx(struct eg20t_port *priv) > fifo_size--; > } > > - while (!uart_tx_stopped(port) && !uart_circ_empty(xmit) && fifo_size) { > - iowrite8(xmit->buf[xmit->tail], priv->membase + PCH_UART_THR); > - uart_xmit_advance(port, 1); > + while (!uart_tx_stopped(port) && fifo_size && > + uart_fifo_get(port, &ch)) { > + iowrite8(ch, priv->membase + PCH_UART_THR); > fifo_size--; > tx_empty = 0; > } > @@ -850,14 +850,14 @@ static unsigned int handle_tx(struct eg20t_port *priv) > static unsigned int dma_handle_tx(struct eg20t_port *priv) > { > struct uart_port *port = &priv->port; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > struct scatterlist *sg; > int nent; > int fifo_size; > struct dma_async_tx_descriptor *desc; > + unsigned int bytes, tail; > int num; > int i; > - int bytes; > int size; > int rem; > > @@ -886,7 +886,7 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv) > fifo_size--; > } > > - bytes = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + bytes = kfifo_out_linear(&tport->xmit_fifo, &tail, UART_XMIT_SIZE); > if (!bytes) { > dev_dbg(priv->port.dev, "%s 0 bytes return\n", __func__); > pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT); > @@ -920,10 +920,10 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv) > > for (i = 0; i < num; i++, sg++) { > if (i == (num - 1)) > - sg_set_page(sg, virt_to_page(xmit->buf), > + sg_set_page(sg, virt_to_page(tport->xmit_buf), > rem, fifo_size * i); > else > - sg_set_page(sg, virt_to_page(xmit->buf), > + sg_set_page(sg, virt_to_page(tport->xmit_buf), > size, fifo_size * i); > } > > @@ -937,8 +937,7 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv) > priv->nent = nent; > > for (i = 0; i < nent; i++, sg++) { > - sg->offset = (xmit->tail & (UART_XMIT_SIZE - 1)) + > - fifo_size * i; > + sg->offset = tail + fifo_size * i; > sg_dma_address(sg) = (sg_dma_address(sg) & > ~(UART_XMIT_SIZE - 1)) + sg->offset; > if (i == (nent - 1)) > diff --git a/drivers/tty/serial/pic32_uart.c b/drivers/tty/serial/pic32_uart.c > index bbb46e6e98a2..f5af336a869b 100644 > --- a/drivers/tty/serial/pic32_uart.c > +++ b/drivers/tty/serial/pic32_uart.c > @@ -342,7 +342,7 @@ static void pic32_uart_do_rx(struct uart_port *port) > static void pic32_uart_do_tx(struct uart_port *port) > { > struct pic32_sport *sport = to_pic32_sport(port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > unsigned int max_count = PIC32_UART_TX_FIFO_DEPTH; > > if (port->x_char) { > @@ -357,7 +357,7 @@ static void pic32_uart_do_tx(struct uart_port *port) > return; > } > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > goto txq_empty; > > /* keep stuffing chars into uart tx buffer > @@ -371,21 +371,20 @@ static void pic32_uart_do_tx(struct uart_port *port) > */ > while (!(PIC32_UART_STA_UTXBF & > pic32_uart_readl(sport, PIC32_UART_STA))) { > - unsigned int c = xmit->buf[xmit->tail]; > + unsigned char c; > > + if (!uart_fifo_get(port, &c)) > + break; > pic32_uart_writel(sport, PIC32_UART_TX, c); > > - uart_xmit_advance(port, 1); > - if (uart_circ_empty(xmit)) > - break; > if (--max_count == 0) > break; > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > goto txq_empty; > > return; > diff --git a/drivers/tty/serial/pmac_zilog.c b/drivers/tty/serial/pmac_zilog.c > index 05d97e89511e..63bc726273fd 100644 > --- a/drivers/tty/serial/pmac_zilog.c > +++ b/drivers/tty/serial/pmac_zilog.c > @@ -347,7 +347,8 @@ static void pmz_status_handle(struct uart_pmac_port *uap) > > static void pmz_transmit_chars(struct uart_pmac_port *uap) > { > - struct circ_buf *xmit; > + struct tty_port *tport; > + unsigned char ch; > > if (ZS_IS_CONS(uap)) { > unsigned char status = read_zsreg(uap, R0); > @@ -398,8 +399,8 @@ static void pmz_transmit_chars(struct uart_pmac_port *uap) > > if (uap->port.state == NULL) > goto ack_tx_int; > - xmit = &uap->port.state->xmit; > - if (uart_circ_empty(xmit)) { > + tport = &uap->port.state->port; > + if (kfifo_is_empty(&tport->xmit_fifo)) { > uart_write_wakeup(&uap->port); > goto ack_tx_int; > } > @@ -407,12 +408,11 @@ static void pmz_transmit_chars(struct uart_pmac_port *uap) > goto ack_tx_int; > > uap->flags |= PMACZILOG_FLAG_TX_ACTIVE; > - write_zsdata(uap, xmit->buf[xmit->tail]); > + WARN_ON(!uart_fifo_get(&uap->port, &ch)); > + write_zsdata(uap, ch); > zssync(uap); > > - uart_xmit_advance(&uap->port, 1); > - > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&uap->port); > > return; > @@ -620,15 +620,15 @@ static void pmz_start_tx(struct uart_port *port) > port->icount.tx++; > port->x_char = 0; > } else { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > + unsigned char ch; > > - if (uart_circ_empty(xmit)) > + if (!uart_fifo_get(&uap->port, &ch)) > return; > - write_zsdata(uap, xmit->buf[xmit->tail]); > + write_zsdata(uap, ch); > zssync(uap); > - uart_xmit_advance(port, 1); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&uap->port); > } > } > diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c > index f9f7ac1a10df..7814982f1921 100644 > --- a/drivers/tty/serial/qcom_geni_serial.c > +++ b/drivers/tty/serial/qcom_geni_serial.c > @@ -505,7 +505,7 @@ static void qcom_geni_serial_console_write(struct console *co, const char *s, > */ > qcom_geni_serial_poll_tx_done(uport); > > - if (!uart_circ_empty(&uport->state->xmit)) { > + if (!kfifo_is_empty(&uport->state->port.xmit_fifo)) { > irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN); > writel(irq_en | M_TX_FIFO_WATERMARK_EN, > uport->membase + SE_GENI_M_IRQ_EN); > @@ -620,22 +620,24 @@ static void qcom_geni_serial_stop_tx_dma(struct uart_port *uport) > static void qcom_geni_serial_start_tx_dma(struct uart_port *uport) > { > struct qcom_geni_serial_port *port = to_dev_port(uport); > - struct circ_buf *xmit = &uport->state->xmit; > + struct tty_port *tport = &uport->state->port; > unsigned int xmit_size; > + u8 *tail; > int ret; > > if (port->tx_dma_addr) > return; > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > return; > > - xmit_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + xmit_size = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, > + UART_XMIT_SIZE); > > qcom_geni_serial_setup_tx(uport, xmit_size); > > - ret = geni_se_tx_dma_prep(&port->se, &xmit->buf[xmit->tail], > - xmit_size, &port->tx_dma_addr); > + ret = geni_se_tx_dma_prep(&port->se, tail, xmit_size, > + &port->tx_dma_addr); > if (ret) { > dev_err(uport->dev, "unable to start TX SE DMA: %d\n", ret); > qcom_geni_serial_stop_tx_dma(uport); > @@ -853,18 +855,16 @@ static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport, > unsigned int chunk) > { > struct qcom_geni_serial_port *port = to_dev_port(uport); > - struct circ_buf *xmit = &uport->state->xmit; > - unsigned int tx_bytes, c, remaining = chunk; > + struct tty_port *tport = &uport->state->port; > + unsigned int tx_bytes, remaining = chunk; > u8 buf[BYTES_PER_FIFO_WORD]; > > while (remaining) { > memset(buf, 0, sizeof(buf)); > tx_bytes = min(remaining, BYTES_PER_FIFO_WORD); > > - for (c = 0; c < tx_bytes ; c++) { > - buf[c] = xmit->buf[xmit->tail]; > - uart_xmit_advance(uport, 1); > - } > + tx_bytes = kfifo_out(&tport->xmit_fifo, buf, tx_bytes); > + uart_xmit_advance(uport, tx_bytes); > > iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1); > > @@ -877,7 +877,7 @@ static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport, > bool done, bool active) > { > struct qcom_geni_serial_port *port = to_dev_port(uport); > - struct circ_buf *xmit = &uport->state->xmit; > + struct tty_port *tport = &uport->state->port; > size_t avail; > size_t pending; > u32 status; > @@ -890,7 +890,7 @@ static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport, > if (active) > pending = port->tx_remaining; > else > - pending = uart_circ_chars_pending(xmit); > + pending = kfifo_len(&tport->xmit_fifo); > > /* All data has been transmitted and acknowledged as received */ > if (!pending && !status && done) { > @@ -933,24 +933,24 @@ static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport, > uport->membase + SE_GENI_M_IRQ_EN); > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(uport); > } > > static void qcom_geni_serial_handle_tx_dma(struct uart_port *uport) > { > struct qcom_geni_serial_port *port = to_dev_port(uport); > - struct circ_buf *xmit = &uport->state->xmit; > + struct tty_port *tport = &uport->state->port; > > uart_xmit_advance(uport, port->tx_remaining); > geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr, port->tx_remaining); > port->tx_dma_addr = 0; > port->tx_remaining = 0; > > - if (!uart_circ_empty(xmit)) > + if (!kfifo_is_empty(&tport->xmit_fifo)) > qcom_geni_serial_start_tx_dma(uport); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(uport); > } > > diff --git a/drivers/tty/serial/rda-uart.c b/drivers/tty/serial/rda-uart.c > index 82def9b8632a..663e35e424bd 100644 > --- a/drivers/tty/serial/rda-uart.c > +++ b/drivers/tty/serial/rda-uart.c > @@ -330,8 +330,8 @@ static void rda_uart_set_termios(struct uart_port *port, > > static void rda_uart_send_chars(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > - unsigned int ch; > + struct tty_port *tport = &port->state->port; > + unsigned char ch; > u32 val; > > if (uart_tx_stopped(port)) > @@ -347,19 +347,14 @@ static void rda_uart_send_chars(struct uart_port *port) > port->x_char = 0; > } > > - while (rda_uart_read(port, RDA_UART_STATUS) & RDA_UART_TX_FIFO_MASK) { > - if (uart_circ_empty(xmit)) > - break; > - > - ch = xmit->buf[xmit->tail]; > + while ((rda_uart_read(port, RDA_UART_STATUS) & RDA_UART_TX_FIFO_MASK) && > + uart_fifo_get(port, &ch)) > rda_uart_write(port, ch, RDA_UART_RXTX_BUFFER); > - uart_xmit_advance(port, 1); > - } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (!uart_circ_empty(xmit)) { > + if (!kfifo_is_empty(&tport->xmit_fifo)) { > /* Re-enable Tx FIFO interrupt */ > val = rda_uart_read(port, RDA_UART_IRQ_MASK); > val |= RDA_UART_TX_DATA_NEEDED; > diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c > index a2d07e05c502..dc35eb77d2ef 100644 > --- a/drivers/tty/serial/samsung_tty.c > +++ b/drivers/tty/serial/samsung_tty.c > @@ -329,7 +329,7 @@ static void s3c24xx_serial_tx_dma_complete(void *args) > { > struct s3c24xx_uart_port *ourport = args; > struct uart_port *port = &ourport->port; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > struct s3c24xx_uart_dma *dma = ourport->dma; > struct dma_tx_state state; > unsigned long flags; > @@ -348,7 +348,7 @@ static void s3c24xx_serial_tx_dma_complete(void *args) > uart_xmit_advance(port, count); > ourport->tx_in_progress = 0; > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > s3c24xx_serial_start_next_tx(ourport); > @@ -431,17 +431,15 @@ static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport) > } > > static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport, > - unsigned int count) > + unsigned int count, unsigned int tail) > { > - struct uart_port *port = &ourport->port; > - struct circ_buf *xmit = &port->state->xmit; > struct s3c24xx_uart_dma *dma = ourport->dma; > > if (ourport->tx_mode != S3C24XX_TX_DMA) > enable_tx_dma(ourport); > > dma->tx_size = count & ~(dma_get_cache_alignment() - 1); > - dma->tx_transfer_addr = dma->tx_addr + xmit->tail; > + dma->tx_transfer_addr = dma->tx_addr + tail; > > dma_sync_single_for_device(dma->tx_chan->device->dev, > dma->tx_transfer_addr, dma->tx_size, > @@ -468,11 +466,11 @@ static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport, > static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport) > { > struct uart_port *port = &ourport->port; > - struct circ_buf *xmit = &port->state->xmit; > - unsigned long count; > + struct tty_port *tport = &port->state->port; > + unsigned int count, tail; > > /* Get data size up to the end of buffer */ > - count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + count = kfifo_out_linear(&tport->xmit_fifo, &tail, UART_XMIT_SIZE); > > if (!count) { > s3c24xx_serial_stop_tx(port); > @@ -481,16 +479,16 @@ static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport) > > if (!ourport->dma || !ourport->dma->tx_chan || > count < ourport->min_dma_size || > - xmit->tail & (dma_get_cache_alignment() - 1)) > + tail & (dma_get_cache_alignment() - 1)) > s3c24xx_serial_start_tx_pio(ourport); > else > - s3c24xx_serial_start_tx_dma(ourport, count); > + s3c24xx_serial_start_tx_dma(ourport, count, tail); > } > > static void s3c24xx_serial_start_tx(struct uart_port *port) > { > struct s3c24xx_uart_port *ourport = to_ourport(port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > if (!ourport->tx_enabled) { > if (port->flags & UPF_CONS_FLOW) > @@ -502,7 +500,8 @@ static void s3c24xx_serial_start_tx(struct uart_port *port) > } > > if (ourport->dma && ourport->dma->tx_chan) { > - if (!uart_circ_empty(xmit) && !ourport->tx_in_progress) > + if (!kfifo_is_empty(&tport->xmit_fifo) && > + !ourport->tx_in_progress) > s3c24xx_serial_start_next_tx(ourport); > } > } > @@ -868,18 +867,19 @@ static irqreturn_t s3c24xx_serial_rx_irq(int irq, void *dev_id) > static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport) > { > struct uart_port *port = &ourport->port; > - struct circ_buf *xmit = &port->state->xmit; > - int count, dma_count = 0; > + struct tty_port *tport = &port->state->port; > + unsigned int count, dma_count = 0, tail; > > - count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + count = kfifo_out_linear(&tport->xmit_fifo, &tail, UART_XMIT_SIZE); > > if (ourport->dma && ourport->dma->tx_chan && > count >= ourport->min_dma_size) { > int align = dma_get_cache_alignment() - > - (xmit->tail & (dma_get_cache_alignment() - 1)); > + (tail & (dma_get_cache_alignment() - 1)); > if (count - align >= ourport->min_dma_size) { > dma_count = count - align; > count = align; > + tail += align; > } > } > > @@ -894,7 +894,7 @@ static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport) > * stopped, disable the uart and exit > */ > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > s3c24xx_serial_stop_tx(port); > return; > } > @@ -906,24 +906,25 @@ static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport) > dma_count = 0; > } > > - while (!uart_circ_empty(xmit) && count > 0) { > - if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull) > + while (!(rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)) { > + unsigned char ch; > + > + if (!uart_fifo_get(port, &ch)) > break; > > - wr_reg(port, S3C2410_UTXH, xmit->buf[xmit->tail]); > - uart_xmit_advance(port, 1); > + wr_reg(port, S3C2410_UTXH, ch); > count--; > } > > if (!count && dma_count) { > - s3c24xx_serial_start_tx_dma(ourport, dma_count); > + s3c24xx_serial_start_tx_dma(ourport, dma_count, tail); > return; > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > s3c24xx_serial_stop_tx(port); > } > > @@ -1118,7 +1119,8 @@ static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p) > > /* TX buffer */ > dma->tx_addr = dma_map_single(dma->tx_chan->device->dev, > - p->port.state->xmit.buf, UART_XMIT_SIZE, > + p->port.state->port.xmit_buf, > + UART_XMIT_SIZE, > DMA_TO_DEVICE); > if (dma_mapping_error(dma->tx_chan->device->dev, dma->tx_addr)) { > reason = "DMA mapping error for TX buffer"; > diff --git a/drivers/tty/serial/sb1250-duart.c b/drivers/tty/serial/sb1250-duart.c > index dbec29d9a6c3..b4e1b90e5960 100644 > --- a/drivers/tty/serial/sb1250-duart.c > +++ b/drivers/tty/serial/sb1250-duart.c > @@ -382,7 +382,8 @@ static void sbd_receive_chars(struct sbd_port *sport) > static void sbd_transmit_chars(struct sbd_port *sport) > { > struct uart_port *uport = &sport->port; > - struct circ_buf *xmit = &sport->port.state->xmit; > + struct tty_port *tport = &sport->port.state->port; > + unsigned char ch; > unsigned int mask; > int stop_tx; > > @@ -395,19 +396,19 @@ static void sbd_transmit_chars(struct sbd_port *sport) > } > > /* If nothing to do or stopped or hardware stopped. */ > - stop_tx = (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)); > + stop_tx = uart_tx_stopped(&sport->port) || > + !uart_fifo_get(&sport->port, &ch); > > /* Send char. */ > if (!stop_tx) { > - write_sbdchn(sport, R_DUART_TX_HOLD, xmit->buf[xmit->tail]); > - uart_xmit_advance(&sport->port, 1); > + write_sbdchn(sport, R_DUART_TX_HOLD, ch); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&sport->port); > } > > /* Are we are done? */ > - if (stop_tx || uart_circ_empty(xmit)) { > + if (stop_tx || kfifo_is_empty(&tport->xmit_fifo)) { > /* Disable tx interrupts. */ > mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2)); > mask &= ~M_DUART_IMR_TX; > diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c > index 929206a9a6e1..c6983b7bd78c 100644 > --- a/drivers/tty/serial/sc16is7xx.c > +++ b/drivers/tty/serial/sc16is7xx.c > @@ -676,9 +676,9 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen, > static void sc16is7xx_handle_tx(struct uart_port *port) > { > struct sc16is7xx_port *s = dev_get_drvdata(port->dev); > - struct circ_buf *xmit = &port->state->xmit; > - unsigned int txlen, to_send, i; > + struct tty_port *tport = &port->state->port; > unsigned long flags; > + unsigned int txlen; > > if (unlikely(port->x_char)) { > sc16is7xx_port_write(port, SC16IS7XX_THR_REG, port->x_char); > @@ -687,40 +687,30 @@ static void sc16is7xx_handle_tx(struct uart_port *port) > return; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > uart_port_lock_irqsave(port, &flags); > sc16is7xx_stop_tx(port); > uart_port_unlock_irqrestore(port, flags); > return; > } > > - /* Get length of data pending in circular buffer */ > - to_send = uart_circ_chars_pending(xmit); > - if (likely(to_send)) { > - /* Limit to space available in TX FIFO */ > - txlen = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG); > - if (txlen > SC16IS7XX_FIFO_SIZE) { > - dev_err_ratelimited(port->dev, > - "chip reports %d free bytes in TX fifo, but it only has %d", > - txlen, SC16IS7XX_FIFO_SIZE); > - txlen = 0; > - } > - to_send = (to_send > txlen) ? txlen : to_send; > - > - /* Convert to linear buffer */ > - for (i = 0; i < to_send; ++i) { > - s->buf[i] = xmit->buf[xmit->tail]; > - uart_xmit_advance(port, 1); > - } > - > - sc16is7xx_fifo_write(port, s->buf, to_send); > + /* Limit to space available in TX FIFO */ > + txlen = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG); > + if (txlen > SC16IS7XX_FIFO_SIZE) { > + dev_err_ratelimited(port->dev, > + "chip reports %d free bytes in TX fifo, but it only has %d", > + txlen, SC16IS7XX_FIFO_SIZE); > + txlen = 0; > } > > + txlen = uart_fifo_out(port, s->buf, txlen); > + sc16is7xx_fifo_write(port, s->buf, txlen); > + > uart_port_lock_irqsave(port, &flags); > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > sc16is7xx_stop_tx(port); > else > sc16is7xx_ier_set(port, SC16IS7XX_IER_THRI_BIT); > diff --git a/drivers/tty/serial/sccnxp.c b/drivers/tty/serial/sccnxp.c > index f24217a560d7..6d1d142fd216 100644 > --- a/drivers/tty/serial/sccnxp.c > +++ b/drivers/tty/serial/sccnxp.c > @@ -439,7 +439,7 @@ static void sccnxp_handle_rx(struct uart_port *port) > static void sccnxp_handle_tx(struct uart_port *port) > { > u8 sr; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > struct sccnxp_port *s = dev_get_drvdata(port->dev); > > if (unlikely(port->x_char)) { > @@ -449,7 +449,7 @@ static void sccnxp_handle_tx(struct uart_port *port) > return; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > /* Disable TX if FIFO is empty */ > if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXEMT) { > sccnxp_disable_irq(port, IMR_TXRDY); > @@ -461,16 +461,20 @@ static void sccnxp_handle_tx(struct uart_port *port) > return; > } > > - while (!uart_circ_empty(xmit)) { > + while (1) { > + unsigned char ch; > + > sr = sccnxp_port_read(port, SCCNXP_SR_REG); > if (!(sr & SR_TXRDY)) > break; > > - sccnxp_port_write(port, SCCNXP_THR_REG, xmit->buf[xmit->tail]); > - uart_xmit_advance(port, 1); > + if (!uart_fifo_get(port, &ch)) > + break; > + > + sccnxp_port_write(port, SCCNXP_THR_REG, ch); > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > } > > diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c > index 525f3a2f7bd4..1183ca54ab92 100644 > --- a/drivers/tty/serial/serial-tegra.c > +++ b/drivers/tty/serial/serial-tegra.c > @@ -484,18 +484,18 @@ static void tegra_uart_release_port(struct uart_port *u) > > static void tegra_uart_fill_tx_fifo(struct tegra_uart_port *tup, int max_bytes) > { > - struct circ_buf *xmit = &tup->uport.state->xmit; > + unsigned char ch; > int i; > > for (i = 0; i < max_bytes; i++) { > - BUG_ON(uart_circ_empty(xmit)); > if (tup->cdata->tx_fifo_full_status) { > unsigned long lsr = tegra_uart_read(tup, UART_LSR); > if ((lsr & TEGRA_UART_LSR_TXFIFO_FULL)) > break; > } > - tegra_uart_write(tup, xmit->buf[xmit->tail], UART_TX); > - uart_xmit_advance(&tup->uport, 1); > + if (WARN_ON_ONCE(!uart_fifo_get(&tup->uport, &ch))) > + break; > + tegra_uart_write(tup, ch, UART_TX); > } > } > > @@ -514,7 +514,7 @@ static void tegra_uart_start_pio_tx(struct tegra_uart_port *tup, > static void tegra_uart_tx_dma_complete(void *args) > { > struct tegra_uart_port *tup = args; > - struct circ_buf *xmit = &tup->uport.state->xmit; > + struct tty_port *tport = &tup->uport.state->port; > struct dma_tx_state state; > unsigned long flags; > unsigned int count; > @@ -525,7 +525,7 @@ static void tegra_uart_tx_dma_complete(void *args) > uart_port_lock_irqsave(&tup->uport, &flags); > uart_xmit_advance(&tup->uport, count); > tup->tx_in_progress = 0; > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&tup->uport); > tegra_uart_start_next_tx(tup); > uart_port_unlock_irqrestore(&tup->uport, flags); > @@ -534,11 +534,14 @@ static void tegra_uart_tx_dma_complete(void *args) > static int tegra_uart_start_tx_dma(struct tegra_uart_port *tup, > unsigned long count) > { > - struct circ_buf *xmit = &tup->uport.state->xmit; > + struct tty_port *tport = &tup->uport.state->port; > dma_addr_t tx_phys_addr; > + unsigned int tail; > > tup->tx_bytes = count & ~(0xF); > - tx_phys_addr = tup->tx_dma_buf_phys + xmit->tail; > + WARN_ON_ONCE(kfifo_out_linear(&tport->xmit_fifo, &tail, > + UART_XMIT_SIZE) < count); > + tx_phys_addr = tup->tx_dma_buf_phys + tail; > > dma_sync_single_for_device(tup->uport.dev, tx_phys_addr, > tup->tx_bytes, DMA_TO_DEVICE); > @@ -562,18 +565,21 @@ static int tegra_uart_start_tx_dma(struct tegra_uart_port *tup, > > static void tegra_uart_start_next_tx(struct tegra_uart_port *tup) > { > + struct tty_port *tport = &tup->uport.state->port; > + unsigned char *tail_ptr; > unsigned long tail; > - unsigned long count; > - struct circ_buf *xmit = &tup->uport.state->xmit; > + unsigned int count; > > if (!tup->current_baud) > return; > > - tail = (unsigned long)&xmit->buf[xmit->tail]; > - count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + count = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail_ptr, > + UART_XMIT_SIZE); > if (!count) > return; > > + tail = (unsigned long)tail_ptr; > + > if (tup->use_tx_pio || count < TEGRA_UART_MIN_DMA) > tegra_uart_start_pio_tx(tup, count); > else if (BYTES_TO_ALIGN(tail) > 0) > @@ -586,9 +592,9 @@ static void tegra_uart_start_next_tx(struct tegra_uart_port *tup) > static void tegra_uart_start_tx(struct uart_port *u) > { > struct tegra_uart_port *tup = to_tegra_uport(u); > - struct circ_buf *xmit = &u->state->xmit; > + struct tty_port *tport = &u->state->port; > > - if (!uart_circ_empty(xmit) && !tup->tx_in_progress) > + if (!kfifo_is_empty(&tport->xmit_fifo) && !tup->tx_in_progress) > tegra_uart_start_next_tx(tup); > } > > @@ -628,11 +634,11 @@ static void tegra_uart_stop_tx(struct uart_port *u) > > static void tegra_uart_handle_tx_pio(struct tegra_uart_port *tup) > { > - struct circ_buf *xmit = &tup->uport.state->xmit; > + struct tty_port *tport = &tup->uport.state->port; > > tegra_uart_fill_tx_fifo(tup, tup->tx_bytes); > tup->tx_in_progress = 0; > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&tup->uport); > tegra_uart_start_next_tx(tup); > } > @@ -1169,15 +1175,14 @@ static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, > tup->rx_dma_buf_virt = dma_buf; > tup->rx_dma_buf_phys = dma_phys; > } else { > + dma_buf = tup->uport.state->port.xmit_buf; > dma_phys = dma_map_single(tup->uport.dev, > - tup->uport.state->xmit.buf, UART_XMIT_SIZE, > - DMA_TO_DEVICE); > + dma_buf, UART_XMIT_SIZE, DMA_TO_DEVICE); > if (dma_mapping_error(tup->uport.dev, dma_phys)) { > dev_err(tup->uport.dev, "dma_map_single tx failed\n"); > dma_release_channel(dma_chan); > return -ENOMEM; > } > - dma_buf = tup->uport.state->xmit.buf; > dma_sconfig.dst_addr = tup->uport.mapbase; > dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; > dma_sconfig.dst_maxburst = 16; > diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c > index ff85ebd3a007..3c0931fba1c6 100644 > --- a/drivers/tty/serial/serial_core.c > +++ b/drivers/tty/serial/serial_core.c > @@ -272,9 +272,10 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state, > return -ENOMEM; > > uart_port_lock(state, flags); > - if (!state->xmit.buf) { > - state->xmit.buf = (unsigned char *) page; > - uart_circ_clear(&state->xmit); > + if (!state->port.xmit_buf) { > + state->port.xmit_buf = (unsigned char *)page; > + kfifo_init(&state->port.xmit_fifo, state->port.xmit_buf, > + PAGE_SIZE); > uart_port_unlock(uport, flags); > } else { > uart_port_unlock(uport, flags); > @@ -387,8 +388,9 @@ static void uart_shutdown(struct tty_struct *tty, struct uart_state *state) > * can endup in printk() recursion. > */ > uart_port_lock(state, flags); > - xmit_buf = state->xmit.buf; > - state->xmit.buf = NULL; > + xmit_buf = port->xmit_buf; > + port->xmit_buf = NULL; > + INIT_KFIFO(port->xmit_fifo); > uart_port_unlock(uport, flags); > > free_page((unsigned long)xmit_buf); > @@ -552,22 +554,17 @@ static int uart_put_char(struct tty_struct *tty, u8 c) > { > struct uart_state *state = tty->driver_data; > struct uart_port *port; > - struct circ_buf *circ; > unsigned long flags; > int ret = 0; > > - circ = &state->xmit; > port = uart_port_lock(state, flags); > - if (!circ->buf) { > + if (WARN_ON_ONCE(!state->port.xmit_buf)) { > uart_port_unlock(port, flags); > return 0; > } > > - if (port && uart_circ_chars_free(circ) != 0) { > - circ->buf[circ->head] = c; > - circ->head = (circ->head + 1) & (UART_XMIT_SIZE - 1); > - ret = 1; > - } > + if (port) > + ret = kfifo_put(&state->port.xmit_fifo, c); > uart_port_unlock(port, flags); > return ret; > } > @@ -581,9 +578,8 @@ static ssize_t uart_write(struct tty_struct *tty, const u8 *buf, size_t count) > { > struct uart_state *state = tty->driver_data; > struct uart_port *port; > - struct circ_buf *circ; > unsigned long flags; > - int c, ret = 0; > + int ret = 0; > > /* > * This means you called this function _after_ the port was > @@ -593,24 +589,13 @@ static ssize_t uart_write(struct tty_struct *tty, const u8 *buf, size_t count) > return -EL3HLT; > > port = uart_port_lock(state, flags); > - circ = &state->xmit; > - if (!circ->buf) { > + if (WARN_ON_ONCE(!state->port.xmit_buf)) { > uart_port_unlock(port, flags); > return 0; > } > > - while (port) { > - c = CIRC_SPACE_TO_END(circ->head, circ->tail, UART_XMIT_SIZE); > - if (count < c) > - c = count; > - if (c <= 0) > - break; > - memcpy(circ->buf + circ->head, buf, c); > - circ->head = (circ->head + c) & (UART_XMIT_SIZE - 1); > - buf += c; > - count -= c; > - ret += c; > - } > + if (port) > + ret = kfifo_in(&state->port.xmit_fifo, buf, count); > > __uart_start(state); > uart_port_unlock(port, flags); > @@ -625,7 +610,7 @@ static unsigned int uart_write_room(struct tty_struct *tty) > unsigned int ret; > > port = uart_port_lock(state, flags); > - ret = uart_circ_chars_free(&state->xmit); > + ret = kfifo_avail(&state->port.xmit_fifo); > uart_port_unlock(port, flags); > return ret; > } > @@ -638,7 +623,7 @@ static unsigned int uart_chars_in_buffer(struct tty_struct *tty) > unsigned int ret; > > port = uart_port_lock(state, flags); > - ret = uart_circ_chars_pending(&state->xmit); > + ret = kfifo_len(&state->port.xmit_fifo); > uart_port_unlock(port, flags); > return ret; > } > @@ -661,7 +646,7 @@ static void uart_flush_buffer(struct tty_struct *tty) > port = uart_port_lock(state, flags); > if (!port) > return; > - uart_circ_clear(&state->xmit); > + kfifo_reset(&state->port.xmit_fifo); > if (port->ops->flush_buffer) > port->ops->flush_buffer(port); > uart_port_unlock(port, flags); > @@ -1064,7 +1049,7 @@ static int uart_get_lsr_info(struct tty_struct *tty, > * interrupt happens). > */ > if (uport->x_char || > - ((uart_circ_chars_pending(&state->xmit) > 0) && > + (!kfifo_is_empty(&state->port.xmit_fifo) && > !uart_tx_stopped(uport))) > result &= ~TIOCSER_TEMT; > > @@ -1788,8 +1773,9 @@ static void uart_tty_port_shutdown(struct tty_port *port) > * Free the transmit buffer. > */ > uart_port_lock_irq(uport); > - buf = state->xmit.buf; > - state->xmit.buf = NULL; > + buf = port->xmit_buf; > + port->xmit_buf = NULL; > + INIT_KFIFO(port->xmit_fifo); > uart_port_unlock_irq(uport); > > free_page((unsigned long)buf); > diff --git a/drivers/tty/serial/serial_port.c b/drivers/tty/serial/serial_port.c > index 22b9eeb23e68..3408c8827561 100644 > --- a/drivers/tty/serial/serial_port.c > +++ b/drivers/tty/serial/serial_port.c > @@ -23,7 +23,7 @@ > static int __serial_port_busy(struct uart_port *port) > { > return !uart_tx_stopped(port) && > - uart_circ_chars_pending(&port->state->xmit); > + !kfifo_is_empty(&port->state->port.xmit_fifo); > } > > static int serial_port_runtime_resume(struct device *dev) > diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c > index e512eaa57ed5..97031db26ae4 100644 > --- a/drivers/tty/serial/sh-sci.c > +++ b/drivers/tty/serial/sh-sci.c > @@ -585,7 +585,7 @@ static void sci_start_tx(struct uart_port *port) > sci_serial_out(port, SCSCR, new); > } > > - if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) && > + if (s->chan_tx && !kfifo_is_empty(&port->state->port.xmit_fifo) && > dma_submit_error(s->cookie_tx)) { > if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) > /* Switch irq from SCIF to DMA */ > @@ -817,7 +817,7 @@ static int sci_rxfill(struct uart_port *port) > > static void sci_transmit_chars(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > unsigned int stopped = uart_tx_stopped(port); > unsigned short status; > unsigned short ctrl; > @@ -826,7 +826,7 @@ static void sci_transmit_chars(struct uart_port *port) > status = sci_serial_in(port, SCxSR); > if (!(status & SCxSR_TDxE(port))) { > ctrl = sci_serial_in(port, SCSCR); > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > ctrl &= ~SCSCR_TIE; > else > ctrl |= SCSCR_TIE; > @@ -842,15 +842,14 @@ static void sci_transmit_chars(struct uart_port *port) > if (port->x_char) { > c = port->x_char; > port->x_char = 0; > - } else if (!uart_circ_empty(xmit) && !stopped) { > - c = xmit->buf[xmit->tail]; > - xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); > - } else if (port->type == PORT_SCI && uart_circ_empty(xmit)) { > - ctrl = sci_serial_in(port, SCSCR); > - ctrl &= ~SCSCR_TE; > - sci_serial_out(port, SCSCR, ctrl); > - return; > - } else { > + } else if (stopped || !kfifo_get(&tport->xmit_fifo, &c)) { > + if (port->type == PORT_SCI && > + kfifo_is_empty(&tport->xmit_fifo)) { > + ctrl = sci_serial_in(port, SCSCR); > + ctrl &= ~SCSCR_TE; > + sci_serial_out(port, SCSCR, ctrl); > + return; > + } > break; > } > > @@ -861,9 +860,9 @@ static void sci_transmit_chars(struct uart_port *port) > > sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port)); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > - if (uart_circ_empty(xmit)) { > + if (kfifo_is_empty(&tport->xmit_fifo)) { > if (port->type == PORT_SCI) { > ctrl = sci_serial_in(port, SCSCR); > ctrl &= ~SCSCR_TIE; > @@ -1199,7 +1198,7 @@ static void sci_dma_tx_complete(void *arg) > { > struct sci_port *s = arg; > struct uart_port *port = &s->port; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > unsigned long flags; > > dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); > @@ -1208,10 +1207,10 @@ static void sci_dma_tx_complete(void *arg) > > uart_xmit_advance(port, s->tx_dma_len); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (!uart_circ_empty(xmit)) { > + if (!kfifo_is_empty(&tport->xmit_fifo)) { > s->cookie_tx = 0; > schedule_work(&s->work_tx); > } else { > @@ -1424,10 +1423,10 @@ static void sci_dma_tx_work_fn(struct work_struct *work) > struct dma_async_tx_descriptor *desc; > struct dma_chan *chan = s->chan_tx; > struct uart_port *port = &s->port; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > unsigned long flags; > + unsigned int tail; > dma_addr_t buf; > - int head, tail; > > /* > * DMA is idle now. > @@ -1437,10 +1436,9 @@ static void sci_dma_tx_work_fn(struct work_struct *work) > * consistent xmit buffer state. > */ > uart_port_lock_irq(port); > - head = xmit->head; > - tail = xmit->tail; > + s->tx_dma_len = kfifo_out_linear(&tport->xmit_fifo, &tail, > + UART_XMIT_SIZE); > buf = s->tx_dma_addr + tail; > - s->tx_dma_len = CIRC_CNT_TO_END(head, tail, UART_XMIT_SIZE); > if (!s->tx_dma_len) { > /* Transmit buffer has been flushed */ > uart_port_unlock_irq(port); > @@ -1469,8 +1467,8 @@ static void sci_dma_tx_work_fn(struct work_struct *work) > } > > uart_port_unlock_irq(port); > - dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n", > - __func__, xmit->buf, tail, head, s->cookie_tx); > + dev_dbg(port->dev, "%s: %p: %u, cookie %d\n", > + __func__, tport->xmit_buf, tail, s->cookie_tx); > > dma_async_issue_pending(chan); > return; > @@ -1585,6 +1583,7 @@ static struct dma_chan *sci_request_dma_chan(struct uart_port *port, > static void sci_request_dma(struct uart_port *port) > { > struct sci_port *s = to_sci_port(port); > + struct tty_port *tport = &port->state->port; > struct dma_chan *chan; > > dev_dbg(port->dev, "%s: port %d\n", __func__, port->line); > @@ -1613,7 +1612,7 @@ static void sci_request_dma(struct uart_port *port) > if (chan) { > /* UART circular tx buffer is an aligned page. */ > s->tx_dma_addr = dma_map_single(chan->device->dev, > - port->state->xmit.buf, > + tport->xmit_buf, > UART_XMIT_SIZE, > DMA_TO_DEVICE); > if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) { > @@ -1622,7 +1621,7 @@ static void sci_request_dma(struct uart_port *port) > } else { > dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n", > __func__, UART_XMIT_SIZE, > - port->state->xmit.buf, &s->tx_dma_addr); > + tport->xmit_buf, &s->tx_dma_addr); > > INIT_WORK(&s->work_tx, sci_dma_tx_work_fn); > s->chan_tx_saved = s->chan_tx = chan; > diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c > index 15f14fa593da..3fc54cc02a1f 100644 > --- a/drivers/tty/serial/sprd_serial.c > +++ b/drivers/tty/serial/sprd_serial.c > @@ -227,13 +227,13 @@ static int sprd_tx_buf_remap(struct uart_port *port) > { > struct sprd_uart_port *sp = > container_of(port, struct sprd_uart_port, port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > + unsigned char *tail; > > - sp->tx_dma.trans_len = > - CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + sp->tx_dma.trans_len = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, > + UART_XMIT_SIZE); > > - sp->tx_dma.phys_addr = dma_map_single(port->dev, > - (void *)&(xmit->buf[xmit->tail]), > + sp->tx_dma.phys_addr = dma_map_single(port->dev, tail, > sp->tx_dma.trans_len, > DMA_TO_DEVICE); > return dma_mapping_error(port->dev, sp->tx_dma.phys_addr); > @@ -244,7 +244,7 @@ static void sprd_complete_tx_dma(void *data) > struct uart_port *port = (struct uart_port *)data; > struct sprd_uart_port *sp = > container_of(port, struct sprd_uart_port, port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > unsigned long flags; > > uart_port_lock_irqsave(port, &flags); > @@ -253,10 +253,10 @@ static void sprd_complete_tx_dma(void *data) > > uart_xmit_advance(port, sp->tx_dma.trans_len); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit) || sprd_tx_buf_remap(port) || > + if (kfifo_is_empty(&tport->xmit_fifo) || sprd_tx_buf_remap(port) || > sprd_tx_dma_config(port)) > sp->tx_dma.trans_len = 0; > > @@ -319,7 +319,7 @@ static void sprd_start_tx_dma(struct uart_port *port) > { > struct sprd_uart_port *sp = > container_of(port, struct sprd_uart_port, port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > if (port->x_char) { > serial_out(port, SPRD_TXD, port->x_char); > @@ -328,7 +328,7 @@ static void sprd_start_tx_dma(struct uart_port *port) > return; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > sprd_stop_tx_dma(port); > return; > } > diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c > index a23e59551848..f91753a40a69 100644 > --- a/drivers/tty/serial/st-asc.c > +++ b/drivers/tty/serial/st-asc.c > @@ -387,9 +387,9 @@ static unsigned int asc_get_mctrl(struct uart_port *port) > /* There are probably characters waiting to be transmitted. */ > static void asc_start_tx(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > - if (!uart_circ_empty(xmit)) > + if (!kfifo_is_empty(&tport->xmit_fifo)) > asc_enable_tx_interrupts(port); > } > > diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c > index 58d169e5c1db..8c66abcfe6ca 100644 > --- a/drivers/tty/serial/stm32-usart.c > +++ b/drivers/tty/serial/stm32-usart.c > @@ -696,18 +696,23 @@ static void stm32_usart_transmit_chars_pio(struct uart_port *port) > { > struct stm32_port *stm32_port = to_stm32_port(port); > const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > + > + while (1) { > + unsigned char ch; > > - while (!uart_circ_empty(xmit)) { > /* Check that TDR is empty before filling FIFO */ > if (!(readl_relaxed(port->membase + ofs->isr) & USART_SR_TXE)) > break; > - writel_relaxed(xmit->buf[xmit->tail], port->membase + ofs->tdr); > - uart_xmit_advance(port, 1); > + > + if (!uart_fifo_get(port, &ch)) > + break; > + > + writel_relaxed(ch, port->membase + ofs->tdr); > } > > /* rely on TXE irq (mask or unmask) for sending remaining data */ > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > stm32_usart_tx_interrupt_disable(port); > else > stm32_usart_tx_interrupt_enable(port); > @@ -716,7 +721,7 @@ static void stm32_usart_transmit_chars_pio(struct uart_port *port) > static void stm32_usart_transmit_chars_dma(struct uart_port *port) > { > struct stm32_port *stm32port = to_stm32_port(port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > struct dma_async_tx_descriptor *desc = NULL; > unsigned int count; > int ret; > @@ -728,25 +733,8 @@ static void stm32_usart_transmit_chars_dma(struct uart_port *port) > return; > } > > - count = uart_circ_chars_pending(xmit); > - > - if (count > TX_BUF_L) > - count = TX_BUF_L; > - > - if (xmit->tail < xmit->head) { > - memcpy(&stm32port->tx_buf[0], &xmit->buf[xmit->tail], count); > - } else { > - size_t one = UART_XMIT_SIZE - xmit->tail; > - size_t two; > - > - if (one > count) > - one = count; > - two = count - one; > - > - memcpy(&stm32port->tx_buf[0], &xmit->buf[xmit->tail], one); > - if (two) > - memcpy(&stm32port->tx_buf[one], &xmit->buf[0], two); > - } > + count = kfifo_out_peek(&tport->xmit_fifo, &stm32port->tx_buf[0], > + TX_BUF_L); > > desc = dmaengine_prep_slave_single(stm32port->tx_ch, > stm32port->tx_dma_buf, > @@ -792,14 +780,14 @@ static void stm32_usart_transmit_chars(struct uart_port *port) > { > struct stm32_port *stm32_port = to_stm32_port(port); > const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > u32 isr; > int ret; > > if (!stm32_port->hw_flow_control && > port->rs485.flags & SER_RS485_ENABLED && > (port->x_char || > - !(uart_circ_empty(xmit) || uart_tx_stopped(port)))) { > + !(kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)))) { > stm32_usart_tc_interrupt_disable(port); > stm32_usart_rs485_rts_enable(port); > } > @@ -826,7 +814,7 @@ static void stm32_usart_transmit_chars(struct uart_port *port) > return; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > stm32_usart_tx_interrupt_disable(port); > return; > } > @@ -841,10 +829,10 @@ static void stm32_usart_transmit_chars(struct uart_port *port) > else > stm32_usart_transmit_chars_pio(port); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit)) { > + if (kfifo_is_empty(&tport->xmit_fifo)) { > stm32_usart_tx_interrupt_disable(port); > if (!stm32_port->hw_flow_control && > port->rs485.flags & SER_RS485_ENABLED) { > @@ -967,9 +955,9 @@ static void stm32_usart_stop_tx(struct uart_port *port) > /* There are probably characters waiting to be transmitted. */ > static void stm32_usart_start_tx(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > - if (uart_circ_empty(xmit) && !port->x_char) { > + if (kfifo_is_empty(&tport->xmit_fifo) && !port->x_char) { > stm32_usart_rs485_rts_disable(port); > return; > } > diff --git a/drivers/tty/serial/sunhv.c b/drivers/tty/serial/sunhv.c > index 8d612ab80680..7f60679fdde1 100644 > --- a/drivers/tty/serial/sunhv.c > +++ b/drivers/tty/serial/sunhv.c > @@ -39,10 +39,13 @@ static char *con_read_page; > > static int hung_up = 0; > > -static void transmit_chars_putchar(struct uart_port *port, struct circ_buf *xmit) > +static void transmit_chars_putchar(struct uart_port *port, > + struct tty_port *tport) > { > - while (!uart_circ_empty(xmit)) { > - long status = sun4v_con_putchar(xmit->buf[xmit->tail]); > + unsigned char ch; > + > + while (kfifo_peek(&tport->xmit_fifo, &ch)) { > + long status = sun4v_con_putchar(ch); > > if (status != HV_EOK) > break; > @@ -51,14 +54,16 @@ static void transmit_chars_putchar(struct uart_port *port, struct circ_buf *xmit > } > } > > -static void transmit_chars_write(struct uart_port *port, struct circ_buf *xmit) > +static void transmit_chars_write(struct uart_port *port, struct tty_port *tport) > { > - while (!uart_circ_empty(xmit)) { > - unsigned long ra = __pa(xmit->buf + xmit->tail); > - unsigned long len, status, sent; > + while (!kfifo_is_empty(&tport->xmit_fifo)) { > + unsigned long len, ra, status, sent; > + unsigned char *tail; > + > + len = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, > + UART_XMIT_SIZE); > + ra = __pa(tail); > > - len = CIRC_CNT_TO_END(xmit->head, xmit->tail, > - UART_XMIT_SIZE); > status = sun4v_con_write(ra, len, &sent); > if (status != HV_EOK) > break; > @@ -165,7 +170,7 @@ static int receive_chars_read(struct uart_port *port) > } > > struct sunhv_ops { > - void (*transmit_chars)(struct uart_port *port, struct circ_buf *xmit); > + void (*transmit_chars)(struct uart_port *port, struct tty_port *tport); > int (*receive_chars)(struct uart_port *port); > }; > > @@ -196,18 +201,18 @@ static struct tty_port *receive_chars(struct uart_port *port) > > static void transmit_chars(struct uart_port *port) > { > - struct circ_buf *xmit; > + struct tty_port *tport; > > if (!port->state) > return; > > - xmit = &port->state->xmit; > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) > + tport = &port->state->port; > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) > return; > > - sunhv_ops->transmit_chars(port, xmit); > + sunhv_ops->transmit_chars(port, tport); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > } > > diff --git a/drivers/tty/serial/sunplus-uart.c b/drivers/tty/serial/sunplus-uart.c > index f5e29eb4a4ce..abf7c449308d 100644 > --- a/drivers/tty/serial/sunplus-uart.c > +++ b/drivers/tty/serial/sunplus-uart.c > @@ -200,7 +200,7 @@ static void sunplus_break_ctl(struct uart_port *port, int ctl) > > static void transmit_chars(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > if (port->x_char) { > sp_uart_put_char(port, port->x_char); > @@ -209,22 +209,24 @@ static void transmit_chars(struct uart_port *port) > return; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > sunplus_stop_tx(port); > return; > } > > do { > - sp_uart_put_char(port, xmit->buf[xmit->tail]); > - uart_xmit_advance(port, 1); > - if (uart_circ_empty(xmit)) > + unsigned char ch; > + > + if (!uart_fifo_get(port, &ch)) > break; > + > + sp_uart_put_char(port, ch); > } while (sunplus_tx_buf_not_full(port)); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > sunplus_stop_tx(port); > } > > diff --git a/drivers/tty/serial/sunsab.c b/drivers/tty/serial/sunsab.c > index 1ea2f33a07a7..1acbe2fba746 100644 > --- a/drivers/tty/serial/sunsab.c > +++ b/drivers/tty/serial/sunsab.c > @@ -232,7 +232,7 @@ static void sunsab_tx_idle(struct uart_sunsab_port *); > static void transmit_chars(struct uart_sunsab_port *up, > union sab82532_irq_status *stat) > { > - struct circ_buf *xmit = &up->port.state->xmit; > + struct tty_port *tport = &up->port.state->port; > int i; > > if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) { > @@ -252,7 +252,7 @@ static void transmit_chars(struct uart_sunsab_port *up, > set_bit(SAB82532_XPR, &up->irqflags); > sunsab_tx_idle(up); > > - if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(&up->port)) { > up->interrupt_mask1 |= SAB82532_IMR1_XPR; > writeb(up->interrupt_mask1, &up->regs->w.imr1); > return; > @@ -265,21 +265,22 @@ static void transmit_chars(struct uart_sunsab_port *up, > /* Stuff 32 bytes into Transmit FIFO. */ > clear_bit(SAB82532_XPR, &up->irqflags); > for (i = 0; i < up->port.fifosize; i++) { > - writeb(xmit->buf[xmit->tail], > - &up->regs->w.xfifo[i]); > - uart_xmit_advance(&up->port, 1); > - if (uart_circ_empty(xmit)) > + unsigned char ch; > + > + if (!uart_fifo_get(&up->port, &ch)) > break; > + > + writeb(ch, &up->regs->w.xfifo[i]); > } > > /* Issue a Transmit Frame command. */ > sunsab_cec_wait(up); > writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&up->port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > sunsab_stop_tx(&up->port); > } > > @@ -435,10 +436,10 @@ static void sunsab_start_tx(struct uart_port *port) > { > struct uart_sunsab_port *up = > container_of(port, struct uart_sunsab_port, port); > - struct circ_buf *xmit = &up->port.state->xmit; > + struct tty_port *tport = &up->port.state->port; > int i; > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) > return; > > up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR); > @@ -451,11 +452,12 @@ static void sunsab_start_tx(struct uart_port *port) > clear_bit(SAB82532_XPR, &up->irqflags); > > for (i = 0; i < up->port.fifosize; i++) { > - writeb(xmit->buf[xmit->tail], > - &up->regs->w.xfifo[i]); > - uart_xmit_advance(&up->port, 1); > - if (uart_circ_empty(xmit)) > + unsigned char ch; > + > + if (!uart_fifo_get(&up->port, &ch)) > break; > + > + writeb(ch, &up->regs->w.xfifo[i]); > } > > /* Issue a Transmit Frame command. */ > diff --git a/drivers/tty/serial/sunsu.c b/drivers/tty/serial/sunsu.c > index c8b65f4b2710..67a5fc70bb4b 100644 > --- a/drivers/tty/serial/sunsu.c > +++ b/drivers/tty/serial/sunsu.c > @@ -396,7 +396,8 @@ receive_chars(struct uart_sunsu_port *up, unsigned char *status) > > static void transmit_chars(struct uart_sunsu_port *up) > { > - struct circ_buf *xmit = &up->port.state->xmit; > + struct tty_port *tport = &up->port.state->port; > + unsigned char ch; > int count; > > if (up->port.x_char) { > @@ -409,23 +410,23 @@ static void transmit_chars(struct uart_sunsu_port *up) > sunsu_stop_tx(&up->port); > return; > } > - if (uart_circ_empty(xmit)) { > + if (kfifo_is_empty(&tport->xmit_fifo)) { > __stop_tx(up); > return; > } > > count = up->port.fifosize; > do { > - serial_out(up, UART_TX, xmit->buf[xmit->tail]); > - uart_xmit_advance(&up->port, 1); > - if (uart_circ_empty(xmit)) > + if (!uart_fifo_get(&up->port, &ch)) > break; > + > + serial_out(up, UART_TX, ch); > } while (--count > 0); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&up->port); > > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > __stop_tx(up); > } > > diff --git a/drivers/tty/serial/sunzilog.c b/drivers/tty/serial/sunzilog.c > index c99289c6c8f8..71758ad4241c 100644 > --- a/drivers/tty/serial/sunzilog.c > +++ b/drivers/tty/serial/sunzilog.c > @@ -453,7 +453,8 @@ static void sunzilog_status_handle(struct uart_sunzilog_port *up, > static void sunzilog_transmit_chars(struct uart_sunzilog_port *up, > struct zilog_channel __iomem *channel) > { > - struct circ_buf *xmit; > + struct tty_port *tport; > + unsigned char ch; > > if (ZS_IS_CONS(up)) { > unsigned char status = readb(&channel->control); > @@ -496,21 +497,20 @@ static void sunzilog_transmit_chars(struct uart_sunzilog_port *up, > > if (up->port.state == NULL) > goto ack_tx_int; > - xmit = &up->port.state->xmit; > - if (uart_circ_empty(xmit)) > - goto ack_tx_int; > + tport = &up->port.state->port; > > if (uart_tx_stopped(&up->port)) > goto ack_tx_int; > > + if (!uart_fifo_get(&up->port, &ch)) > + goto ack_tx_int; > + > up->flags |= SUNZILOG_FLAG_TX_ACTIVE; > - writeb(xmit->buf[xmit->tail], &channel->data); > + writeb(ch, &channel->data); > ZSDELAY(); > ZS_WSYNC(channel); > > - uart_xmit_advance(&up->port, 1); > - > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&up->port); > > return; > @@ -700,17 +700,16 @@ static void sunzilog_start_tx(struct uart_port *port) > port->icount.tx++; > port->x_char = 0; > } else { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > + unsigned char ch; > > - if (uart_circ_empty(xmit)) > + if (!uart_fifo_get(&up->port, &ch)) > return; > - writeb(xmit->buf[xmit->tail], &channel->data); > + writeb(ch, &channel->data); > ZSDELAY(); > ZS_WSYNC(channel); > > - uart_xmit_advance(port, 1); > - > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&up->port); > } > } > diff --git a/drivers/tty/serial/tegra-tcu.c b/drivers/tty/serial/tegra-tcu.c > index d9c78320eb02..21ca5fcadf49 100644 > --- a/drivers/tty/serial/tegra-tcu.c > +++ b/drivers/tty/serial/tegra-tcu.c > @@ -91,15 +91,17 @@ static void tegra_tcu_write(struct tegra_tcu *tcu, const char *s, > static void tegra_tcu_uart_start_tx(struct uart_port *port) > { > struct tegra_tcu *tcu = port->private_data; > - struct circ_buf *xmit = &port->state->xmit; > - unsigned long count; > + struct tty_port *tport = &port->state->port; > + unsigned char *tail; > + unsigned int count; > > for (;;) { > - count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); > + count = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, > + UART_XMIT_SIZE); > if (!count) > break; > > - tegra_tcu_write(tcu, &xmit->buf[xmit->tail], count); > + tegra_tcu_write(tcu, tail, count); > uart_xmit_advance(port, count); > } > > diff --git a/drivers/tty/serial/timbuart.c b/drivers/tty/serial/timbuart.c > index 4bc89a9b380a..43fa0938b5e3 100644 > --- a/drivers/tty/serial/timbuart.c > +++ b/drivers/tty/serial/timbuart.c > @@ -95,14 +95,11 @@ static void timbuart_rx_chars(struct uart_port *port) > > static void timbuart_tx_chars(struct uart_port *port) > { > - struct circ_buf *xmit = &port->state->xmit; > + unsigned char ch; > > while (!(ioread32(port->membase + TIMBUART_ISR) & TXBF) && > - !uart_circ_empty(xmit)) { > - iowrite8(xmit->buf[xmit->tail], > - port->membase + TIMBUART_TXFIFO); > - uart_xmit_advance(port, 1); > - } > + uart_fifo_get(port, &ch)) > + iowrite8(ch, port->membase + TIMBUART_TXFIFO); > > dev_dbg(port->dev, > "%s - total written %d bytes, CTL: %x, RTS: %x, baud: %x\n", > @@ -117,9 +114,9 @@ static void timbuart_handle_tx_port(struct uart_port *port, u32 isr, u32 *ier) > { > struct timbuart_port *uart = > container_of(port, struct timbuart_port, port); > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) > return; > > if (port->x_char) > @@ -130,7 +127,7 @@ static void timbuart_handle_tx_port(struct uart_port *port, u32 isr, u32 *ier) > /* clear all TX interrupts */ > iowrite32(TXFLAGS, port->membase + TIMBUART_ISR); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > } else > /* Re-enable any tx interrupt */ > @@ -141,7 +138,7 @@ static void timbuart_handle_tx_port(struct uart_port *port, u32 isr, u32 *ier) > * we wake up the upper layer later when we got the interrupt > * to give it some time to go out... > */ > - if (!uart_circ_empty(xmit)) > + if (!kfifo_is_empty(&tport->xmit_fifo)) > *ier |= TXBAE; > > dev_dbg(port->dev, "%s - leaving\n", __func__); > diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c > index 10ba41b7be99..68357ac8ffe3 100644 > --- a/drivers/tty/serial/uartlite.c > +++ b/drivers/tty/serial/uartlite.c > @@ -189,7 +189,8 @@ static int ulite_receive(struct uart_port *port, int stat) > > static int ulite_transmit(struct uart_port *port, int stat) > { > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > + unsigned char ch; > > if (stat & ULITE_STATUS_TXFULL) > return 0; > @@ -201,14 +202,16 @@ static int ulite_transmit(struct uart_port *port, int stat) > return 1; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) > + if (uart_tx_stopped(port)) > + return 0; > + > + if (!uart_fifo_get(port, &ch)) > return 0; > > - uart_out32(xmit->buf[xmit->tail], ULITE_TX, port); > - uart_xmit_advance(port, 1); > + uart_out32(ch, ULITE_TX, port); > > /* wake up */ > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > return 1; > diff --git a/drivers/tty/serial/ucc_uart.c b/drivers/tty/serial/ucc_uart.c > index 397b95dff7ed..53bb8c5ef499 100644 > --- a/drivers/tty/serial/ucc_uart.c > +++ b/drivers/tty/serial/ucc_uart.c > @@ -334,7 +334,7 @@ static int qe_uart_tx_pump(struct uart_qe_port *qe_port) > unsigned char *p; > unsigned int count; > struct uart_port *port = &qe_port->port; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > > /* Handle xon/xoff */ > if (port->x_char) { > @@ -358,7 +358,7 @@ static int qe_uart_tx_pump(struct uart_qe_port *qe_port) > return 1; > } > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > qe_uart_stop_tx(port); > return 0; > } > @@ -366,16 +366,10 @@ static int qe_uart_tx_pump(struct uart_qe_port *qe_port) > /* Pick next descriptor and fill from buffer */ > bdp = qe_port->tx_cur; > > - while (!(ioread16be(&bdp->status) & BD_SC_READY) && !uart_circ_empty(xmit)) { > - count = 0; > + while (!(ioread16be(&bdp->status) & BD_SC_READY) && > + !kfifo_is_empty(&tport->xmit_fifo)) { > p = qe2cpu_addr(ioread32be(&bdp->buf), qe_port); > - while (count < qe_port->tx_fifosize) { > - *p++ = xmit->buf[xmit->tail]; > - uart_xmit_advance(port, 1); > - count++; > - if (uart_circ_empty(xmit)) > - break; > - } > + count = uart_fifo_out(port, p, qe_port->tx_fifosize); > > iowrite16be(count, &bdp->length); > qe_setbits_be16(&bdp->status, BD_SC_READY); > @@ -388,10 +382,10 @@ static int qe_uart_tx_pump(struct uart_qe_port *qe_port) > } > qe_port->tx_cur = bdp; > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > - if (uart_circ_empty(xmit)) { > + if (kfifo_is_empty(&tport->xmit_fifo)) { > /* The kernel buffer is empty, so turn off TX interrupts. We > don't need to be told when the QE is finished transmitting > the data. */ > diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c > index 5f48ec37cb25..de3487206bcb 100644 > --- a/drivers/tty/serial/xilinx_uartps.c > +++ b/drivers/tty/serial/xilinx_uartps.c > @@ -425,32 +425,32 @@ static void cdns_uart_handle_tx(void *dev_id) > { > struct uart_port *port = (struct uart_port *)dev_id; > struct cdns_uart *cdns_uart = port->private_data; > - struct circ_buf *xmit = &port->state->xmit; > + struct tty_port *tport = &port->state->port; > unsigned int numbytes; > + unsigned char ch; > > - if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { > + if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { > /* Disable the TX Empty interrupt */ > writel(CDNS_UART_IXR_TXEMPTY, port->membase + CDNS_UART_IDR); > return; > } > > numbytes = port->fifosize; > - while (numbytes && !uart_circ_empty(xmit) && > - !(readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL)) { > - > - writel(xmit->buf[xmit->tail], port->membase + CDNS_UART_FIFO); > - uart_xmit_advance(port, 1); > + while (numbytes && > + !(readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL) && > + uart_fifo_get(port, &ch)) { > + writel(ch, port->membase + CDNS_UART_FIFO); > numbytes--; > } > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(port); > > /* Enable the TX Empty interrupt */ > writel(CDNS_UART_IXR_TXEMPTY, cdns_uart->port->membase + CDNS_UART_IER); > > if (cdns_uart->port->rs485.flags & SER_RS485_ENABLED && > - (uart_circ_empty(xmit) || uart_tx_stopped(port))) { > + (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port))) { > cdns_uart->tx_timer.function = &cdns_rs485_rx_callback; > hrtimer_start(&cdns_uart->tx_timer, > ns_to_ktime(cdns_calc_after_tx_delay(cdns_uart)), HRTIMER_MODE_REL); > @@ -723,7 +723,7 @@ static void cdns_uart_start_tx(struct uart_port *port) > status |= CDNS_UART_CR_TX_EN; > writel(status, port->membase + CDNS_UART_CR); > > - if (uart_circ_empty(&port->state->xmit)) > + if (kfifo_is_empty(&port->state->port.xmit_fifo)) > return; > > /* Clear the TX Empty interrupt */ > diff --git a/drivers/tty/serial/zs.c b/drivers/tty/serial/zs.c > index 65ca4da6e368..79ea7108a0f3 100644 > --- a/drivers/tty/serial/zs.c > +++ b/drivers/tty/serial/zs.c > @@ -606,7 +606,8 @@ static void zs_receive_chars(struct zs_port *zport) > > static void zs_raw_transmit_chars(struct zs_port *zport) > { > - struct circ_buf *xmit = &zport->port.state->xmit; > + struct tty_port *tport = &zport->port.state->port; > + unsigned char ch; > > /* XON/XOFF chars. */ > if (zport->port.x_char) { > @@ -617,20 +618,20 @@ static void zs_raw_transmit_chars(struct zs_port *zport) > } > > /* If nothing to do or stopped or hardware stopped. */ > - if (uart_circ_empty(xmit) || uart_tx_stopped(&zport->port)) { > + if (uart_tx_stopped(&zport->port) || > + !uart_fifo_get(&zport->port, &ch)) { > zs_raw_stop_tx(zport); > return; > } > > /* Send char. */ > - write_zsdata(zport, xmit->buf[xmit->tail]); > - uart_xmit_advance(&zport->port, 1); > + write_zsdata(zport, ch); > > - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) > uart_write_wakeup(&zport->port); > > /* Are we are done? */ > - if (uart_circ_empty(xmit)) > + if (kfifo_is_empty(&tport->xmit_fifo)) > zs_raw_stop_tx(zport); > } > > diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h > index 0a0f6e21d40e..8cb65f50e830 100644 > --- a/include/linux/serial_core.h > +++ b/include/linux/serial_core.h > @@ -11,7 +11,6 @@ > #include <linux/compiler.h> > #include <linux/console.h> > #include <linux/interrupt.h> > -#include <linux/circ_buf.h> > #include <linux/spinlock.h> > #include <linux/sched.h> > #include <linux/tty.h> > @@ -699,7 +698,6 @@ struct uart_state { > struct tty_port port; > > enum uart_pm_state pm_state; > - struct circ_buf xmit; > > atomic_t refcount; > wait_queue_head_t remove_wait; > @@ -723,12 +721,35 @@ struct uart_state { > */ > static inline void uart_xmit_advance(struct uart_port *up, unsigned int chars) > { > - struct circ_buf *xmit = &up->state->xmit; > + struct tty_port *tport = &up->state->port; > > - xmit->tail = (xmit->tail + chars) & (UART_XMIT_SIZE - 1); > + kfifo_skip_count(&tport->xmit_fifo, chars); > up->icount.tx += chars; > } > > +static inline unsigned int uart_fifo_out(struct uart_port *up, > + unsigned char *buf, unsigned int chars) > +{ > + struct tty_port *tport = &up->state->port; > + > + chars = kfifo_out(&tport->xmit_fifo, buf, chars); > + up->icount.tx += chars; > + > + return chars; > +} > + > +static inline unsigned int uart_fifo_get(struct uart_port *up, > + unsigned char *ch) > +{ > + struct tty_port *tport = &up->state->port; > + unsigned int chars; > + > + chars = kfifo_get(&tport->xmit_fifo, ch); > + up->icount.tx += chars; > + > + return chars; > +} > + > struct module; > struct tty_driver; > > @@ -764,7 +785,7 @@ enum UART_TX_FLAGS { > for_test, for_post) \ > ({ \ > struct uart_port *__port = (uport); \ > - struct circ_buf *xmit = &__port->state->xmit; \ > + struct tty_port *__tport = &__port->state->port; \ > unsigned int pending; \ > \ > for (; (for_test) && (tx_ready); (for_post), __port->icount.tx++) { \ > @@ -775,17 +796,18 @@ enum UART_TX_FLAGS { > continue; \ > } \ > \ > - if (uart_circ_empty(xmit) || uart_tx_stopped(__port)) \ > + if (uart_tx_stopped(__port)) \ > + break; \ > + \ > + if (!kfifo_get(&__tport->xmit_fifo, &(ch))) \ > break; \ > \ > - (ch) = xmit->buf[xmit->tail]; \ > (put_char); \ > - xmit->tail = (xmit->tail + 1) % UART_XMIT_SIZE; \ > } \ > \ > (tx_done); \ > \ > - pending = uart_circ_chars_pending(xmit); \ > + pending = kfifo_len(&__tport->xmit_fifo); \ > if (pending < WAKEUP_CHARS) { \ > uart_write_wakeup(__port); \ > \ > @@ -974,15 +996,6 @@ bool uart_match_port(const struct uart_port *port1, > int uart_suspend_port(struct uart_driver *reg, struct uart_port *port); > int uart_resume_port(struct uart_driver *reg, struct uart_port *port); > > -#define uart_circ_empty(circ) ((circ)->head == (circ)->tail) > -#define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0) > - > -#define uart_circ_chars_pending(circ) \ > - (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE)) > - > -#define uart_circ_chars_free(circ) \ > - (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE)) > - > static inline int uart_tx_stopped(struct uart_port *port) > { > struct tty_struct *tty = port->state->port.tty; > -- > 2.44.0 >
