[PATCH 4.20 047/171] scsi: scsi_debug: fix write_same with virtual_gb problem

Greg Kroah-Hartman
2019-03-12T17:12:28Z

[ Upstream commit 40d07b523cf434f252b134c86b1f8f2d907ffb0b ]

The WRITE SAME(10) and (16) implementations didn't take account of the
buffer wrap required when the virtual_gb parameter is greater than 0.

Fix that and rename the fake_store() function to lba2fake_store() to lessen
confusion with the global fake_storep pointer. Bump version date.

Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Reported-by: Bart Van Assche <bvanassche@acm.org>
Tested by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/scsi_debug.c | 41 ++++++++++++++++++++-------------------
1 file changed, 21 insertions(+), 20 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 60bcc6df97a9..65305b3848bc 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -62,7 +62,7 @@

/* make sure inq_product_rev string corresponds to this version */
#define SDEBUG_VERSION "0188" /* format to fit INQUIRY revision field */
-static const char *sdebug_version_date = "20180128";
+static const char *sdebug_version_date = "20190125";

#define MY_NAME "scsi_debug"

@@ -735,7 +735,7 @@ static inline bool scsi_debug_lbp(void)
(sdebug_lbpu || sdebug_lbpws || sdebug_lbpws10);
}

-static void *fake_store(unsigned long long lba)
+static void *lba2fake_store(unsigned long long lba)
{
lba = do_div(lba, sdebug_store_sectors);

@@ -2514,8 +2514,8 @@ static int do_device_access(struct scsi_cmnd *scmd, u32 sg_skip, u64 lba,
return ret;
}

-/* If fake_store(lba,num) compares equal to arr(num), then copy top half of
- * arr into fake_store(lba,num) and return true. If comparison fails then
+/* If lba2fake_store(lba,num) compares equal to arr(num), then copy top half of
+ * arr into lba2fake_store(lba,num) and return true. If comparison fails then
* return false. */
static bool comp_write_worker(u64 lba, u32 num, const u8 *arr)
{
@@ -2643,7 +2643,7 @@ static int prot_verify_read(struct scsi_cmnd *SCpnt, sector_t start_sec,
if (sdt->app_tag == cpu_to_be16(0xffff))
continue;

- ret = dif_verify(sdt, fake_store(sector), sector, ei_lba);
+ ret = dif_verify(sdt, lba2fake_store(sector), sector, ei_lba);
if (ret) {
dif_errors++;
return ret;
@@ -3261,10 +3261,12 @@ static int resp_write_scat(struct scsi_cmnd *scp,
static int resp_write_same(struct scsi_cmnd *scp, u64 lba, u32 num,
u32 ei_lba, bool unmap, bool ndob)
{
+ int ret;
unsigned long iflags;
unsigned long long i;
- int ret;
- u64 lba_off;
+ u32 lb_size = sdebug_sector_size;
+ u64 block, lbaa;
+ u8 *fs1p;

ret = check_device_access_params(scp, lba, num);
if (ret)
@@ -3276,31 +3278,30 @@ static int resp_write_same(struct scsi_cmnd *scp, u64 lba, u32 num,
unmap_region(lba, num);
goto out;
}
-
- lba_off = lba * sdebug_sector_size;
+ lbaa = lba;
+ block = do_div(lbaa, sdebug_store_sectors);
/* if ndob then zero 1 logical block, else fetch 1 logical block */
+ fs1p = fake_storep + (block * lb_size);
if (ndob) {
- memset(fake_storep + lba_off, 0, sdebug_sector_size);
+ memset(fs1p, 0, lb_size);
ret = 0;
} else
- ret = fetch_to_dev_buffer(scp, fake_storep + lba_off,
- sdebug_sector_size);
+ ret = fetch_to_dev_buffer(scp, fs1p, lb_size);

if (-1 == ret) {
write_unlock_irqrestore(&atomic_rw, iflags);
return DID_ERROR << 16;
- } else if (sdebug_verbose && !ndob && (ret < sdebug_sector_size))
+ } else if (sdebug_verbose && !ndob && (ret < lb_size))
sdev_printk(KERN_INFO, scp->device,
"%s: %s: lb size=%u, IO sent=%d bytes\n",
- my_name, "write same",
- sdebug_sector_size, ret);
+ my_name, "write same", lb_size, ret);

/* Copy first sector to remaining blocks */
- for (i = 1 ; i < num ; i++)
- memcpy(fake_storep + ((lba + i) * sdebug_sector_size),
- fake_storep + lba_off,
- sdebug_sector_size);
-
+ for (i = 1 ; i < num ; i++) {
+ lbaa = lba + i;
+ block = do_div(lbaa, sdebug_store_sectors);
+ memmove(fake_storep + (block * lb_size), fs1p, lb_size);
+ }
if (scsi_debug_lbp())
map_region(lba, num);
out:
--
2.19.1