--- On Mon, 11/8/10, Matthew Wilcox <willy@xxxxxxxxxxxxxxx> wrote:
> -0700, Luben Tuikov wrote:
> > Eliminate an infinite loop whereby the SCSI layer
> > would reissue a command (which would be failed by
> > the driver) ad infinitum. (Invariably due to the
> > driver's profuse use of the
> > SCSI_MLQUEUE_DEVICE_BUSY returned result in its
> > queuecommand() method.)
> >
> > Also add a debug option and a few debug prints.
>
> Why have you added your own debug scheme instead of using
> dev_dbg?
Because, this debug "scheme" produces copious and otherwise unnecessary volume of debug information in a working driver. And because you can turn it on/off just for this driver. It is intended to be used only for debugging this driver and the UAS device(s) to which the driver communicates. 99.9% of the time, this setting will be a 'N' out there. And this is what the Kconfig help entry says: "If unsure, say 'N'."
> You've made a lot of other random whitespace changes too.
> I'll pick through this and see what I like in it.
Yes, it's my emacs. I didn't find a setting to right-justify a continuing argument list of a function definition, nor have I seen this in the kernel before (since 2000 A.D. at least). Have you tried a function declaration instead, in this style? Do you think it would look good in a header file with more than one declaration?
>
> > Signed-off-by: Luben Tuikov <ltuikov@xxxxxxxxx>
> > ---
> > drivers/usb/storage/Kconfig
> | 10 ++++
> > drivers/usb/storage/Makefile | 4
> ++
> > drivers/usb/storage/uas.c |
> 102 +++++++++++++++++++++++++++--------------
> > 3 files changed, 81 insertions(+), 35
> deletions(-)
> >
> > diff --git a/drivers/usb/storage/Kconfig
> b/drivers/usb/storage/Kconfig
> > index 49a489e..eb9f6af 100644
> > --- a/drivers/usb/storage/Kconfig
> > +++ b/drivers/usb/storage/Kconfig
> > @@ -185,6 +185,16 @@ config USB_UAS
> >
> > If you compile this
> driver as a module, it will be named uas.
> >
> > +config USB_UAS_DEBUG
> > + bool "Compile in
> debug mode"
> > + default n
> > + depends on USB_UAS
> > + help
> > + Compiles the uas driver
> in debug mode. In debug mode,
> > + the driver prints debug
> messages to the console.
> > +
> > + If unsure, say 'N'.
> > +
> > config USB_LIBUSUAL
> > bool "The shared table of
> common (or usual) storage devices"
> > depends on USB
> > diff --git a/drivers/usb/storage/Makefile
> b/drivers/usb/storage/Makefile
> > index fcf14cd..16715ab 100644
> > --- a/drivers/usb/storage/Makefile
> > +++ b/drivers/usb/storage/Makefile
> > @@ -10,6 +10,10 @@ ccflags-y := -Idrivers/scsi
> > obj-$(CONFIG_USB_UAS)
> += uas.o
> > obj-$(CONFIG_USB_STORAGE) +=
> usb-storage.o
> >
> > +ifeq ($(CONFIG_USB_UAS_DEBUG),y)
> > + EXTRA_CFLAGS += -DUAS_DEBUG
> > +endif
> > +
> > usb-storage-y := scsiglue.o protocol.o
> transport.o usb.o
> > usb-storage-y += initializers.o sierra_ms.o
> option_ms.o
> >
> > diff --git a/drivers/usb/storage/uas.c
> b/drivers/usb/storage/uas.c
> > index 48dc2b8..ef6e707 100644
> > --- a/drivers/usb/storage/uas.c
> > +++ b/drivers/usb/storage/uas.c
> > @@ -21,6 +21,14 @@
> > #include <scsi/scsi_host.h>
> > #include <scsi/scsi_tcq.h>
> >
> > +#define uas_printk(fmt, ...)
> printk(KERN_NOTICE "uas: " fmt, ## __VA_ARGS__)
> > +
> > +#ifdef UAS_DEBUG
> > +#define UAS_DPRINTK uas_printk
> > +#else
> > +#define UAS_DPRINTK(fmt, ...)
> > +#endif
> > +
> > /* Common header for all IUs */
> > struct iu {
> > __u8 iu_id;
> > @@ -128,6 +136,7 @@ static void uas_do_work(struct
> work_struct *work)
> > {
> > struct uas_cmd_info
> *cmdinfo;
> > struct list_head list;
> > + int res;
> >
> >
> spin_lock_irq(&uas_work_lock);
> >
> list_replace_init(&uas_work_list, &list);
> > @@ -136,8 +145,10 @@ static void uas_do_work(struct
> work_struct *work)
> > list_for_each_entry(cmdinfo,
> &list, list) {
> > struct
> scsi_pointer *scp = (void *)cmdinfo;
> > struct
> scsi_cmnd *cmnd = container_of(scp,
> > -
>
> struct scsi_cmnd,
> SCp);
> > -
> uas_submit_urbs(cmnd, cmnd->device->hostdata,
> GFP_KERNEL);
> > +
>
> struct scsi_cmnd,
> SCp);
> > + res =
> uas_submit_urbs(cmnd, cmnd->device->hostdata,
> GFP_KERNEL);
> > +
> UAS_DPRINTK("%s: cmd:%p, res:%d, state:0x%x\n",
> __FUNCTION__,
> > +
> cmnd, res,
> cmdinfo->state);
> > }
> > }
> >
> > @@ -198,13 +209,15 @@ static void uas_sense_old(struct
> urb *urb, struct scsi_cmnd *cmnd)
> > }
> >
> > static void uas_xfer_data(struct urb *urb,
> struct scsi_cmnd *cmnd,
> > -
>
> unsigned direction)
> > +
> unsigned direction)
> > {
> > struct uas_cmd_info *cmdinfo
> = (void *)&cmnd->SCp;
> > int err;
> >
> > cmdinfo->state = direction
> | SUBMIT_STATUS_URB;
> > err = uas_submit_urbs(cmnd,
> cmnd->device->hostdata, GFP_ATOMIC);
> > + UAS_DPRINTK("%s: cmd:%p, err:%d,
> state:0x%x\n", __FUNCTION__,
> > +
> cmnd, err, cmdinfo->state);
> > if (err) {
> >
> spin_lock(&uas_work_lock);
> >
> list_add_tail(&cmdinfo->list, &uas_work_list);
> > @@ -222,7 +235,8 @@ static void uas_stat_cmplt(struct
> urb *urb)
> > u16 tag;
> >
> > if (urb->status) {
> > -
> dev_err(&urb->dev->dev, "URB BAD STATUS %d\n",
> urb->status);
> > +
> dev_err(&urb->dev->dev, "%s: URB BAD STATUS
> %d\n",
> > +
> __FUNCTION__, urb->status);
> >
> usb_free_urb(urb);
> > return;
> > }
> > @@ -259,6 +273,14 @@ static void uas_stat_cmplt(struct
> urb *urb)
> > static void uas_data_cmplt(struct urb *urb)
> > {
> > struct scsi_data_buffer *sdb
> = urb->context;
> > +
> > + if (urb->status) {
> > +
> dev_err(&urb->dev->dev, "%s: URB BAD STATUS
> %d\n",
> > +
> __FUNCTION__, urb->status);
> > +
> usb_free_urb(urb);
> > + return;
> > + }
> > +
> > sdb->resid =
> sdb->length - urb->actual_length;
> > usb_free_urb(urb);
> > }
> > @@ -339,7 +361,7 @@ static struct urb
> *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
> > memcpy(iu->cdb,
> cmnd->cmnd, cmnd->cmd_len);
> >
> > usb_fill_bulk_urb(urb, udev,
> devinfo->cmd_pipe, iu, sizeof(*iu) + len,
> > -
>
> usb_free_urb, NULL);
> > +
> usb_free_urb, NULL);
> > urb->transfer_flags |=
> URB_FREE_BUFFER;
> > out:
> > return urb;
> > @@ -355,23 +377,26 @@ static struct urb
> *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
> > */
> >
> > static int uas_submit_urbs(struct scsi_cmnd
> *cmnd,
> > -
>
> struct uas_dev_info *devinfo, gfp_t gfp)
> > +
> struct uas_dev_info
> *devinfo, gfp_t gfp)
> > {
> > struct uas_cmd_info *cmdinfo
> = (void *)&cmnd->SCp;
> > + int res;
> >
> > if (cmdinfo->state &
> ALLOC_STATUS_URB) {
> >
> cmdinfo->status_urb = uas_alloc_sense_urb(devinfo, gfp,
> cmnd,
> >
>
>
> cmdinfo->stream);
> > if
> (!cmdinfo->status_urb)
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > +
> return -ENOMEM;
> >
> cmdinfo->state &= ~ALLOC_STATUS_URB;
> > }
> >
> > if (cmdinfo->state &
> SUBMIT_STATUS_URB) {
> > - if
> (usb_submit_urb(cmdinfo->status_urb, gfp)) {
> > + res =
> usb_submit_urb(cmdinfo->status_urb, gfp);
> > + if (res) {
> >
> scmd_printk(KERN_INFO, cmnd,
> > -
>
> "sense urb submission failure\n");
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > +
> "sense
> urb submission failure (%d)\n",
> > +
> res);
> > +
> return res;
> > }
> >
> cmdinfo->state &= ~SUBMIT_STATUS_URB;
> > }
> > @@ -381,15 +406,17 @@ static int
> uas_submit_urbs(struct scsi_cmnd *cmnd,
> >
>
> devinfo->data_in_pipe, cmdinfo->stream,
> >
>
> scsi_in(cmnd), DMA_FROM_DEVICE);
> > if
> (!cmdinfo->data_in_urb)
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > +
> return -ENOMEM;
> >
> cmdinfo->state &= ~ALLOC_DATA_IN_URB;
> > }
> >
> > if (cmdinfo->state &
> SUBMIT_DATA_IN_URB) {
> > - if
> (usb_submit_urb(cmdinfo->data_in_urb, gfp)) {
> > + res =
> usb_submit_urb(cmdinfo->data_in_urb, gfp);
> > + if (res) {
> >
> scmd_printk(KERN_INFO, cmnd,
> > -
>
> "data in urb submission failure\n");
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > +
> "data in
> urb submission failure (%d)\n",
> > +
> res);
> > +
> return res;
> > }
> >
> cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
> > }
> > @@ -399,15 +426,17 @@ static int
> uas_submit_urbs(struct scsi_cmnd *cmnd,
> >
>
> devinfo->data_out_pipe, cmdinfo->stream,
> >
>
> scsi_out(cmnd), DMA_TO_DEVICE);
> > if
> (!cmdinfo->data_out_urb)
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > +
> return -ENOMEM;
> >
> cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
> > }
> >
> > if (cmdinfo->state &
> SUBMIT_DATA_OUT_URB) {
> > - if
> (usb_submit_urb(cmdinfo->data_out_urb, gfp)) {
> > + res =
> usb_submit_urb(cmdinfo->data_out_urb, gfp);
> > + if (res) {
> >
> scmd_printk(KERN_INFO, cmnd,
> > -
>
> "data out urb submission failure\n");
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > +
> "data
> out urb submission failure (%d)\n",
> > +
> res);
> > +
> return res;
> > }
> >
> cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
> > }
> > @@ -416,15 +445,16 @@ static int
> uas_submit_urbs(struct scsi_cmnd *cmnd,
> >
> cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, gfp, cmnd,
> >
>
> cmdinfo->stream);
> > if
> (!cmdinfo->cmd_urb)
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > +
> return -ENOMEM;
> >
> cmdinfo->state &= ~ALLOC_CMD_URB;
> > }
> >
> > if (cmdinfo->state &
> SUBMIT_CMD_URB) {
> > - if
> (usb_submit_urb(cmdinfo->cmd_urb, gfp)) {
> > + res =
> usb_submit_urb(cmdinfo->cmd_urb, gfp);
> > + if (res) {
> >
> scmd_printk(KERN_INFO, cmnd,
> > -
>
> "cmd urb submission failure\n");
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > +
> "cmd urb
> submission failure (%d)\n", res);
> > +
> return res;
> > }
> >
> cmdinfo->state &= ~SUBMIT_CMD_URB;
> > }
> > @@ -433,12 +463,12 @@ static int
> uas_submit_urbs(struct scsi_cmnd *cmnd,
> > }
> >
> > static int uas_queuecommand(struct scsi_cmnd
> *cmnd,
> > -
>
> void (*done)(struct scsi_cmnd *))
> > +
> void (*done)(struct
> scsi_cmnd *))
> > {
> > struct scsi_device *sdev =
> cmnd->device;
> > struct uas_dev_info *devinfo
> = sdev->hostdata;
> > struct uas_cmd_info *cmdinfo
> = (void *)&cmnd->SCp;
> > - int err;
> > + int res;
> >
> > BUILD_BUG_ON(sizeof(struct
> uas_cmd_info) > sizeof(struct scsi_pointer));
> >
> > @@ -474,17 +504,19 @@ static int
> uas_queuecommand(struct scsi_cmnd *cmnd,
> >
> cmdinfo->stream = 0;
> > }
> >
> > - err = uas_submit_urbs(cmnd,
> devinfo, GFP_ATOMIC);
> > - if (err) {
> > - /* If we did
> nothing, give up now */
> > - if
> (cmdinfo->state & SUBMIT_STATUS_URB) {
> > -
> usb_free_urb(cmdinfo->status_urb);
> > -
> return SCSI_MLQUEUE_DEVICE_BUSY;
> > - }
> > -
> spin_lock(&uas_work_lock);
> > -
> list_add_tail(&cmdinfo->list, &uas_work_list);
> > -
> spin_unlock(&uas_work_lock);
> > -
> schedule_work(&uas_work);
> > + res = uas_submit_urbs(cmnd,
> devinfo, GFP_ATOMIC);
> > + UAS_DPRINTK("%s: cmd:%p (0x%02x),
> err:%d, state:0x%x\n", __FUNCTION__,
> > +
> cmnd, cmnd->cmnd[0], res, cmdinfo->state);
> > + if (res) {
> > +
> usb_unlink_urb(cmdinfo->status_urb);
> > +
> usb_unlink_urb(cmdinfo->data_in_urb);
> > +
> usb_unlink_urb(cmdinfo->data_out_urb);
> > +
> usb_unlink_urb(cmdinfo->cmd_urb);
> > +
> > +
> sdev->current_cmnd = NULL;
> > +
> > + cmnd->result
> = DID_NO_CONNECT << 16;
> > + done(cmnd);
> > }
> >
> > return 0;
> > --
> > 1.7.0.1
>
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