From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
This patch (as1233) makes g_file_storage use the "unaligned" accessors.
This is based on work originally done by Harvey Harrison.
Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Acked-by: Harvey Harrison <harvey.harrison@xxxxxxxxx>
Acked-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/usb/gadget/file_storage.c | 93 +++++++++++++++++--------------------
1 files changed, 42 insertions(+), 51 deletions(-)
diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c
index 381a53b..1e6aa50 100644
--- a/drivers/usb/gadget/file_storage.c
+++ b/drivers/usb/gadget/file_storage.c
@@ -248,6 +248,8 @@
#include <linux/freezer.h>
#include <linux/utsname.h>
+#include <asm/unaligned.h>
+
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
@@ -799,29 +801,9 @@ static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
/* Routines for unaligned data access */
-static u16 get_be16(u8 *buf)
-{
- return ((u16) buf[0] << 8) | ((u16) buf[1]);
-}
-
-static u32 get_be32(u8 *buf)
-{
- return ((u32) buf[0] << 24) | ((u32) buf[1] << 16) |
- ((u32) buf[2] << 8) | ((u32) buf[3]);
-}
-
-static void put_be16(u8 *buf, u16 val)
-{
- buf[0] = val >> 8;
- buf[1] = val;
-}
-
-static void put_be32(u8 *buf, u32 val)
+static u32 get_unaligned_be24(u8 *buf)
{
- buf[0] = val >> 24;
- buf[1] = val >> 16;
- buf[2] = val >> 8;
- buf[3] = val & 0xff;
+ return 0xffffff & (u32) get_unaligned_be32(buf - 1);
}
@@ -1582,9 +1564,9 @@ static int do_read(struct fsg_dev *fsg)
/* Get the starting Logical Block Address and check that it's
* not too big */
if (fsg->cmnd[0] == SC_READ_6)
- lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]);
+ lba = get_unaligned_be24(&fsg->cmnd[1]);
else {
- lba = get_be32(&fsg->cmnd[2]);
+ lba = get_unaligned_be32(&fsg->cmnd[2]);
/* We allow DPO (Disable Page Out = don't save data in the
* cache) and FUA (Force Unit Access = don't read from the
@@ -1717,9 +1699,9 @@ static int do_write(struct fsg_dev *fsg)
/* Get the starting Logical Block Address and check that it's
* not too big */
if (fsg->cmnd[0] == SC_WRITE_6)
- lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]);
+ lba = get_unaligned_be24(&fsg->cmnd[1]);
else {
- lba = get_be32(&fsg->cmnd[2]);
+ lba = get_unaligned_be32(&fsg->cmnd[2]);
/* We allow DPO (Disable Page Out = don't save data in the
* cache) and FUA (Force Unit Access = write directly to the
@@ -1940,7 +1922,7 @@ static int do_verify(struct fsg_dev *fsg)
/* Get the starting Logical Block Address and check that it's
* not too big */
- lba = get_be32(&fsg->cmnd[2]);
+ lba = get_unaligned_be32(&fsg->cmnd[2]);
if (lba >= curlun->num_sectors) {
curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
return -EINVAL;
@@ -1953,7 +1935,7 @@ static int do_verify(struct fsg_dev *fsg)
return -EINVAL;
}
- verification_length = get_be16(&fsg->cmnd[7]);
+ verification_length = get_unaligned_be16(&fsg->cmnd[7]);
if (unlikely(verification_length == 0))
return -EIO; // No default reply
@@ -2103,7 +2085,7 @@ static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
memset(buf, 0, 18);
buf[0] = valid | 0x70; // Valid, current error
buf[2] = SK(sd);
- put_be32(&buf[3], sdinfo); // Sense information
+ put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
buf[7] = 18 - 8; // Additional sense length
buf[12] = ASC(sd);
buf[13] = ASCQ(sd);
@@ -2114,7 +2096,7 @@ static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->curlun;
- u32 lba = get_be32(&fsg->cmnd[2]);
+ u32 lba = get_unaligned_be32(&fsg->cmnd[2]);
int pmi = fsg->cmnd[8];
u8 *buf = (u8 *) bh->buf;
@@ -2124,8 +2106,9 @@ static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
return -EINVAL;
}
- put_be32(&buf[0], curlun->num_sectors - 1); // Max logical block
- put_be32(&buf[4], 512); // Block length
+ put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
+ /* Max logical block */
+ put_unaligned_be32(512, &buf[4]); /* Block length */
return 8;
}
@@ -2144,7 +2127,7 @@ static void store_cdrom_address(u8 *dest, int msf, u32 addr)
dest[0] = 0; /* Reserved */
} else {
/* Absolute sector */
- put_be32(dest, addr);
+ put_unaligned_be32(addr, dest);
}
}
@@ -2152,7 +2135,7 @@ static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
struct lun *curlun = fsg->curlun;
int msf = fsg->cmnd[1] & 0x02;
- u32 lba = get_be32(&fsg->cmnd[2]);
+ u32 lba = get_unaligned_be32(&fsg->cmnd[2]);
u8 *buf = (u8 *) bh->buf;
if ((fsg->cmnd[1] & ~0x02) != 0) { /* Mask away MSF */
@@ -2252,10 +2235,13 @@ static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
buf[2] = 0x04; // Write cache enable,
// Read cache not disabled
// No cache retention priorities
- put_be16(&buf[4], 0xffff); // Don't disable prefetch
- // Minimum prefetch = 0
- put_be16(&buf[8], 0xffff); // Maximum prefetch
- put_be16(&buf[10], 0xffff); // Maximum prefetch ceiling
+ put_unaligned_be16(0xffff, &buf[4]);
+ /* Don't disable prefetch */
+ /* Minimum prefetch = 0 */
+ put_unaligned_be16(0xffff, &buf[8]);
+ /* Maximum prefetch */
+ put_unaligned_be16(0xffff, &buf[10]);
+ /* Maximum prefetch ceiling */
}
buf += 12;
}
@@ -2272,7 +2258,7 @@ static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
if (mscmnd == SC_MODE_SENSE_6)
buf0[0] = len - 1;
else
- put_be16(buf0, len - 2);
+ put_unaligned_be16(len - 2, buf0);
return len;
}
@@ -2360,9 +2346,10 @@ static int do_read_format_capacities(struct fsg_dev *fsg,
buf[3] = 8; // Only the Current/Maximum Capacity Descriptor
buf += 4;
- put_be32(&buf[0], curlun->num_sectors); // Number of blocks
- put_be32(&buf[4], 512); // Block length
- buf[4] = 0x02; // Current capacity
+ put_unaligned_be32(curlun->num_sectors, &buf[0]);
+ /* Number of blocks */
+ put_unaligned_be32(512, &buf[4]); /* Block length */
+ buf[4] = 0x02; /* Current capacity */
return 12;
}
@@ -2882,7 +2869,7 @@ static int do_scsi_command(struct fsg_dev *fsg)
break;
case SC_MODE_SELECT_10:
- fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
+ fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
(1<<1) | (3<<7), 0,
"MODE SELECT(10)")) == 0)
@@ -2898,7 +2885,7 @@ static int do_scsi_command(struct fsg_dev *fsg)
break;
case SC_MODE_SENSE_10:
- fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
+ fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(1<<1) | (1<<2) | (3<<7), 0,
"MODE SENSE(10)")) == 0)
@@ -2923,7 +2910,8 @@ static int do_scsi_command(struct fsg_dev *fsg)
break;
case SC_READ_10:
- fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9;
+ fsg->data_size_from_cmnd =
+ get_unaligned_be16(&fsg->cmnd[7]) << 9;
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(1<<1) | (0xf<<2) | (3<<7), 1,
"READ(10)")) == 0)
@@ -2931,7 +2919,8 @@ static int do_scsi_command(struct fsg_dev *fsg)
break;
case SC_READ_12:
- fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9;
+ fsg->data_size_from_cmnd =
+ get_unaligned_be32(&fsg->cmnd[6]) << 9;
if ((reply = check_command(fsg, 12, DATA_DIR_TO_HOST,
(1<<1) | (0xf<<2) | (0xf<<6), 1,
"READ(12)")) == 0)
@@ -2949,7 +2938,7 @@ static int do_scsi_command(struct fsg_dev *fsg)
case SC_READ_HEADER:
if (!mod_data.cdrom)
goto unknown_cmnd;
- fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
+ fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(3<<7) | (0x1f<<1), 1,
"READ HEADER")) == 0)
@@ -2959,7 +2948,7 @@ static int do_scsi_command(struct fsg_dev *fsg)
case SC_READ_TOC:
if (!mod_data.cdrom)
goto unknown_cmnd;
- fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
+ fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(7<<6) | (1<<1), 1,
"READ TOC")) == 0)
@@ -2967,7 +2956,7 @@ static int do_scsi_command(struct fsg_dev *fsg)
break;
case SC_READ_FORMAT_CAPACITIES:
- fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
+ fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
(3<<7), 1,
"READ FORMAT CAPACITIES")) == 0)
@@ -3025,7 +3014,8 @@ static int do_scsi_command(struct fsg_dev *fsg)
break;
case SC_WRITE_10:
- fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9;
+ fsg->data_size_from_cmnd =
+ get_unaligned_be16(&fsg->cmnd[7]) << 9;
if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
(1<<1) | (0xf<<2) | (3<<7), 1,
"WRITE(10)")) == 0)
@@ -3033,7 +3023,8 @@ static int do_scsi_command(struct fsg_dev *fsg)
break;
case SC_WRITE_12:
- fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9;
+ fsg->data_size_from_cmnd =
+ get_unaligned_be32(&fsg->cmnd[6]) << 9;
if ((reply = check_command(fsg, 12, DATA_DIR_FROM_HOST,
(1<<1) | (0xf<<2) | (0xf<<6), 1,
"WRITE(12)")) == 0)
--
1.6.3.2
--
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