libata: SCT Write Same / DSM Trim

Correct handling of devices with sector_size other that 512 bytes.

In the case of a 4Kn device sector_size it is possible to describe a much
larger DSM Trim than the current fixed default of 512 bytes.

This patch assumes the minimum descriptor is sector_size and fills out
the descriptor accordingly.

The ACS-2 specification is quite clear that the DSM command payload is
sized as number of 512 byte transfers so a 4Kn device will operate
correctly without this patch.

Signed-off-by: Shaun Tancheff <shaun.tancheff@seagate.com>
Acked-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Shaun Tancheff 2016-08-24 13:08:14 -05:00 committed by Tejun Heo
parent 7b20309428
commit ef2d7392c4

View file

@ -3283,7 +3283,7 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
/**
* ata_format_dsm_trim_descr() - SATL Write Same to DSM Trim
* @cmd: SCSI command being translated
* @num: Maximum number of entries (nominally 64).
* @trmax: Maximum number of entries that will fit in sector_size bytes.
* @sector: Starting sector
* @count: Total Range of request in logical sectors
*
@ -3298,63 +3298,80 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
* LBA's should be sorted order and not overlap.
*
* NOTE: this is the same format as ADD LBA(S) TO NV CACHE PINNED SET
*
* Return: Number of bytes copied into sglist.
*/
static unsigned int ata_format_dsm_trim_descr(struct scsi_cmnd *cmd, u32 num,
u64 sector, u32 count)
static size_t ata_format_dsm_trim_descr(struct scsi_cmnd *cmd, u32 trmax,
u64 sector, u32 count)
{
__le64 *buffer;
u32 i = 0, used_bytes;
struct scsi_device *sdp = cmd->device;
size_t len = sdp->sector_size;
size_t r;
__le64 *buf;
u32 i = 0;
unsigned long flags;
BUILD_BUG_ON(512 > ATA_SCSI_RBUF_SIZE);
WARN_ON(len > ATA_SCSI_RBUF_SIZE);
if (len > ATA_SCSI_RBUF_SIZE)
len = ATA_SCSI_RBUF_SIZE;
spin_lock_irqsave(&ata_scsi_rbuf_lock, flags);
buffer = ((void *)ata_scsi_rbuf);
while (i < num) {
buf = ((void *)ata_scsi_rbuf);
memset(buf, 0, len);
while (i < trmax) {
u64 entry = sector |
((u64)(count > 0xffff ? 0xffff : count) << 48);
buffer[i++] = __cpu_to_le64(entry);
buf[i++] = __cpu_to_le64(entry);
if (count <= 0xffff)
break;
count -= 0xffff;
sector += 0xffff;
}
used_bytes = ALIGN(i * 8, 512);
memset(buffer + i, 0, used_bytes - i * 8);
sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), buffer, 512);
r = sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), buf, len);
spin_unlock_irqrestore(&ata_scsi_rbuf_lock, flags);
return used_bytes;
return r;
}
/**
* ata_format_dsm_trim_descr() - SATL Write Same to ATA SCT Write Same
* @cmd: SCSI command being translated
* @lba: Starting sector
* @num: Number of logical sectors to be zero'd.
* @num: Number of sectors to be zero'd.
*
* Rewrite the WRITE SAME descriptor to be an SCT Write Same formatted
* Rewrite the WRITE SAME payload to be an SCT Write Same formatted
* descriptor.
* NOTE: Writes a pattern (0's) in the foreground.
* Large write-same requents can timeout.
*
* Return: Number of bytes copied into sglist.
*/
static void ata_format_sct_write_same(struct scsi_cmnd *cmd, u64 lba, u64 num)
static size_t ata_format_sct_write_same(struct scsi_cmnd *cmd, u64 lba, u64 num)
{
u16 *sctpg;
struct scsi_device *sdp = cmd->device;
size_t len = sdp->sector_size;
size_t r;
u16 *buf;
unsigned long flags;
spin_lock_irqsave(&ata_scsi_rbuf_lock, flags);
sctpg = ((void *)ata_scsi_rbuf);
buf = ((void *)ata_scsi_rbuf);
put_unaligned_le16(0x0002, &sctpg[0]); /* SCT_ACT_WRITE_SAME */
put_unaligned_le16(0x0101, &sctpg[1]); /* WRITE PTRN FG */
put_unaligned_le64(lba, &sctpg[2]);
put_unaligned_le64(num, &sctpg[6]);
put_unaligned_le32(0u, &sctpg[10]);
put_unaligned_le16(0x0002, &buf[0]); /* SCT_ACT_WRITE_SAME */
put_unaligned_le16(0x0101, &buf[1]); /* WRITE PTRN FG */
put_unaligned_le64(lba, &buf[2]);
put_unaligned_le64(num, &buf[6]);
put_unaligned_le32(0u, &buf[10]); /* pattern */
sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), sctpg, 512);
WARN_ON(len > ATA_SCSI_RBUF_SIZE);
if (len > ATA_SCSI_RBUF_SIZE)
len = ATA_SCSI_RBUF_SIZE;
r = sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), buf, len);
spin_unlock_irqrestore(&ata_scsi_rbuf_lock, flags);
return r;
}
/**
@ -3371,11 +3388,13 @@ static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
{
struct ata_taskfile *tf = &qc->tf;
struct scsi_cmnd *scmd = qc->scsicmd;
struct scsi_device *sdp = scmd->device;
size_t len = sdp->sector_size;
struct ata_device *dev = qc->dev;
const u8 *cdb = scmd->cmnd;
u64 block;
u32 n_block;
const u32 trmax = ATA_MAX_TRIM_RNUM;
const u32 trmax = len >> 3;
u32 size;
u16 fp;
u8 bp = 0xff;
@ -3420,8 +3439,16 @@ static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
if (!scsi_sg_count(scmd))
goto invalid_param_len;
/*
* size must match sector size in bytes
* For DATA SET MANAGEMENT TRIM in ACS-2 nsect (aka count)
* is defined as number of 512 byte blocks to be transferred.
*/
if (unmap) {
size = ata_format_dsm_trim_descr(scmd, trmax, block, n_block);
if (size != len)
goto invalid_param_len;
if (ata_ncq_enabled(dev) && ata_fpdma_dsm_supported(dev)) {
/* Newer devices support queued TRIM commands */
tf->protocol = ATA_PROT_NCQ;
@ -3441,7 +3468,9 @@ static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
tf->command = ATA_CMD_DSM;
}
} else {
ata_format_sct_write_same(scmd, block, n_block);
size = ata_format_sct_write_same(scmd, block, n_block);
if (size != len)
goto invalid_param_len;
tf->hob_feature = 0;
tf->feature = 0;