Due to reported problems with Write Same on ATA devices,
commit 0ce1b18c42a5 ("libata: Some drives failing on SCT Write Same")
strived to report non-support for Write Same on non-zoned ATA devices.
However, due to the following control flow in sd_config_write_same() this
doesn't always take effect, namely if the ->max_ws_blocks as set in the
by the ATA Identify Device exceeds SD_WS10_BLOCKS:
if (sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS)
[...]
else if (sdkp->ws16 || sdkp->ws10 || sdkp->device->no_report_opcodes)
[...]
else {
sdkp->device->no_write_same = 1;
sdkp->max_ws_blocks = 0;
}
Since commit e73c23ff736e ("block: add async variant of
blkdev_issue_zeroout"), blkdev_issue_zeroout() got a little bit more
sensitive towards failing Write Sames on devices that claim to support them
and this results in messages like
EXT4-fs (dm-1): Delayed block allocation failed for inode 2625094 at
logical offset 2032 with max blocks 2 with error 121
EXT4-fs (dm-1): This should not happen!! Data will be lost
The block limits VPD page of the device in question quotes a value of
0x3fffc0 > 0xffff == SD_MAX_WS10_BLOCKS for the device in question.
The error code 121 is EREMOTEIO which gets asserted by scsi_io_completion()
in case of invalid requests due to invalid command opcodes.
Fix this by doing the sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS handling
only if some kind of Write Same support is reported, i.e. only if
sdkp->ws16 || sdkp->ws10 || sdkp->device->no_report_opcodes
holds. Let the handling code for the non-support case thus take effect,
if needed.
Fixes: e73c23ff736e ("block: add async variant of blkdev_issue_zeroout")
Fixes: 0ce1b18c42a5 ("libata: Some drives failing on SCT Write Same")
Signed-off-by: Nicolai Stange <nicsta...@gmail.com>
---
Applicable to next-20161202.
drivers/scsi/sd.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 2cfeb3c..ef1bab5 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -806,18 +806,21 @@ static void sd_config_write_same(struct scsi_disk *sdkp)
goto out;
}
- /* Some devices can not handle block counts above 0xffff despite
- * supporting WRITE SAME(16). Consequently we default to 64k
- * blocks per I/O unless the device explicitly advertises a
- * bigger limit.
- */
- if (sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS)
- sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
- (u32)SD_MAX_WS16_BLOCKS);
- else if (sdkp->ws16 || sdkp->ws10 || sdkp->device->no_report_opcodes)
- sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
- (u32)SD_MAX_WS10_BLOCKS);
- else {
+ if (sdkp->ws16 || sdkp->ws10 || sdkp->device->no_report_opcodes) {
+ /*
+ * Some devices can not handle block counts above 0xffff despite
+ * supporting WRITE SAME(16). Consequently we default to 64k
+ * blocks per I/O unless the device explicitly advertises a
+ * bigger limit.
+ */
+ if (sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS) {
+ sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
+ (u32)SD_MAX_WS16_BLOCKS);
+ } else {
+ sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
+ (u32)SD_MAX_WS10_BLOCKS);
+ }
+ } else {
sdkp->device->no_write_same = 1;
sdkp->max_ws_blocks = 0;
}
--
2.10.2
