[SCSI] sd: Logical Block Provisioning update
SBC3r26 contains many changes to the Logical Block Provisioning
interfaces (formerly known as Thin Provisioning ditto). This patch
implements support for both the old and new schemes using the same
heuristic as before (whether the LBP VPD page is present).
The new code also allows the provisioning mode (i.e. choice of command)
to be overridden on a per-device basis via sysfs. Two additional modes
are supported in this version:
- WRITE SAME(10) with the UNMAP bit set
- WRITE SAME(10) without the UNMAP bit set. This allows us to support
devices that predate the TP/LBP enhancements in SBC3 and which work
by way zero-detection
Switching between modes has been consolidated in a helper function that
also updates the block layer topology according to the limitations of
the chosen command.
I experimented with trying WRITE SAME(16) if UNMAP fails, WRITE SAME(10)
if WRITE SAME(16) fails, etc. but found several devices that got
cranky. So for now we'll disable discard if one of the commands
fail. The user still has the option of selecting a different mode in
sysfs.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
index c9d8f6c..6ad798b 100644
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -43,6 +43,15 @@
SD_MEMPOOL_SIZE = 2, /* CDB pool size */
};
+enum {
+ SD_LBP_FULL = 0, /* Full logical block provisioning */
+ SD_LBP_UNMAP, /* Use UNMAP command */
+ SD_LBP_WS16, /* Use WRITE SAME(16) with UNMAP bit */
+ SD_LBP_WS10, /* Use WRITE SAME(10) with UNMAP bit */
+ SD_LBP_ZERO, /* Use WRITE SAME(10) with zero payload */
+ SD_LBP_DISABLE, /* Discard disabled due to failed cmd */
+};
+
struct scsi_disk {
struct scsi_driver *driver; /* always &sd_template */
struct scsi_device *device;
@@ -50,21 +59,27 @@
struct gendisk *disk;
atomic_t openers;
sector_t capacity; /* size in 512-byte sectors */
+ u32 max_ws_blocks;
+ u32 max_unmap_blocks;
+ u32 unmap_granularity;
+ u32 unmap_alignment;
u32 index;
unsigned int physical_block_size;
u8 media_present;
u8 write_prot;
u8 protection_type;/* Data Integrity Field */
+ u8 provisioning_mode;
unsigned ATO : 1; /* state of disk ATO bit */
unsigned WCE : 1; /* state of disk WCE bit */
unsigned RCD : 1; /* state of disk RCD bit, unused */
unsigned DPOFUA : 1; /* state of disk DPOFUA bit */
unsigned first_scan : 1;
- unsigned thin_provisioning : 1;
- unsigned unmap : 1;
- unsigned tpws : 1;
- unsigned tpu : 1;
- unsigned tpvpd : 1;
+ unsigned lbpme : 1;
+ unsigned lbprz : 1;
+ unsigned lbpu : 1;
+ unsigned lbpws : 1;
+ unsigned lbpws10 : 1;
+ unsigned lbpvpd : 1;
};
#define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)