From: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Introduce the command duration limits helper function
sd_cdl_cmd_limit() to retrieve and set the DLD bits of the
READ/WRITE 16 and READ/WRITE 32 commands to indicate to the device
the command duration limit descriptor to apply to the command.
When command duration limits are enabled, sd_cdl_cmd_limit() obtains the
index of the descriptor to apply to the command for requests that have
the IOPRIO_CLASS_DL priority class with a priority data sepcifying a
valid descriptor index (1 to 7).
The read-write sysfs attribute "enable" is introduced to control
setting the command duration limits indexes. If this attribute is set
to 0 (default), command duration limits specified by the user are
ignored. The user must set this attribute to 1 for command duration
limits to be set. Enabling and disabling the command duration limits
feature for ATA devices must be done using the ATA feature sub-page of
the control mode page. The sd_cdl_enable() function is introduced to
check if this mode page is supported by the device and if it is, use
it to enable/disable CDL.
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Co-developed-by: Niklas Cassel <niklas.cassel@xxxxxxx>
Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxx>
---
drivers/scsi/sd.c | 16 +++--
drivers/scsi/sd.h | 10 ++++
drivers/scsi/sd_cdl.c | 134 +++++++++++++++++++++++++++++++++++++++++-
3 files changed, 152 insertions(+), 8 deletions(-)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 7879a5470773..d2eb01337943 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1045,13 +1045,14 @@ static blk_status_t sd_setup_flush_cmnd(struct scsi_cmnd *cmd)
static blk_status_t sd_setup_rw32_cmnd(struct scsi_cmnd *cmd, bool write,
sector_t lba, unsigned int nr_blocks,
- unsigned char flags)
+ unsigned char flags, unsigned int dld)
{
cmd->cmd_len = SD_EXT_CDB_SIZE;
cmd->cmnd[0] = VARIABLE_LENGTH_CMD;
cmd->cmnd[7] = 0x18; /* Additional CDB len */
cmd->cmnd[9] = write ? WRITE_32 : READ_32;
cmd->cmnd[10] = flags;
+ cmd->cmnd[11] = dld & 0x07;
put_unaligned_be64(lba, &cmd->cmnd[12]);
put_unaligned_be32(lba, &cmd->cmnd[20]); /* Expected Indirect LBA */
put_unaligned_be32(nr_blocks, &cmd->cmnd[28]);
@@ -1061,12 +1062,12 @@ static blk_status_t sd_setup_rw32_cmnd(struct scsi_cmnd *cmd, bool write,
static blk_status_t sd_setup_rw16_cmnd(struct scsi_cmnd *cmd, bool write,
sector_t lba, unsigned int nr_blocks,
- unsigned char flags)
+ unsigned char flags, unsigned int dld)
{
cmd->cmd_len = 16;
cmd->cmnd[0] = write ? WRITE_16 : READ_16;
- cmd->cmnd[1] = flags;
- cmd->cmnd[14] = 0;
+ cmd->cmnd[1] = flags | ((dld >> 2) & 0x01);
+ cmd->cmnd[14] = (dld & 0x03) << 6;
cmd->cmnd[15] = 0;
put_unaligned_be64(lba, &cmd->cmnd[2]);
put_unaligned_be32(nr_blocks, &cmd->cmnd[10]);
@@ -1129,6 +1130,7 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
unsigned int mask = logical_to_sectors(sdp, 1) - 1;
bool write = rq_data_dir(rq) == WRITE;
unsigned char protect, fua;
+ unsigned int dld = 0;
blk_status_t ret;
unsigned int dif;
bool dix;
@@ -1178,6 +1180,8 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
fua = rq->cmd_flags & REQ_FUA ? 0x8 : 0;
dix = scsi_prot_sg_count(cmd);
dif = scsi_host_dif_capable(cmd->device->host, sdkp->protection_type);
+ if (sd_cdl_enabled(sdkp))
+ dld = sd_cdl_dld(sdkp, cmd);
if (dif || dix)
protect = sd_setup_protect_cmnd(cmd, dix, dif);
@@ -1186,10 +1190,10 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
if (protect && sdkp->protection_type == T10_PI_TYPE2_PROTECTION) {
ret = sd_setup_rw32_cmnd(cmd, write, lba, nr_blocks,
- protect | fua);
+ protect | fua, dld);
} else if (sdp->use_16_for_rw || (nr_blocks > 0xffff)) {
ret = sd_setup_rw16_cmnd(cmd, write, lba, nr_blocks,
- protect | fua);
+ protect | fua, dld);
} else if ((nr_blocks > 0xff) || (lba > 0x1fffff) ||
sdp->use_10_for_rw || protect) {
ret = sd_setup_rw10_cmnd(cmd, write, lba, nr_blocks,
diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
index e60d33bd222a..5b6b6dc4b92d 100644
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -130,8 +130,11 @@ struct sd_cdl_page {
struct sd_cdl_desc descs[SD_CDL_MAX_DESC];
};
+struct scsi_disk;
+
struct sd_cdl {
struct kobject kobj;
+ struct scsi_disk *sdkp;
bool sysfs_registered;
u8 perf_vs_duration_guideline;
struct sd_cdl_page pages[SD_CDL_RW];
@@ -188,6 +191,7 @@ struct scsi_disk {
u8 zeroing_mode;
u8 nr_actuators; /* Number of actuators */
struct sd_cdl *cdl;
+ unsigned cdl_enabled : 1;
unsigned ATO : 1; /* state of disk ATO bit */
unsigned cache_override : 1; /* temp override of WCE,RCD */
unsigned WCE : 1; /* state of disk WCE bit */
@@ -355,5 +359,11 @@ void sd_print_result(const struct scsi_disk *sdkp, const char *msg, int result);
/* Command duration limits support (in sd_cdl.c) */
void sd_read_cdl(struct scsi_disk *sdkp, unsigned char *buf);
void sd_cdl_release(struct scsi_disk *sdkp);
+int sd_cdl_dld(struct scsi_disk *sdkp, struct scsi_cmnd *scmd);
+
+static inline bool sd_cdl_enabled(struct scsi_disk *sdkp)
+{
+ return sdkp->cdl && sdkp->cdl_enabled;
+}
#endif /* _SCSI_DISK_H */
diff --git a/drivers/scsi/sd_cdl.c b/drivers/scsi/sd_cdl.c
index 513cd989f19a..59d02dbb5ea1 100644
--- a/drivers/scsi/sd_cdl.c
+++ b/drivers/scsi/sd_cdl.c
@@ -93,6 +93,63 @@ static const char *sd_cdl_policy_name(u8 policy)
}
}
+/*
+ * Enable/disable CDL.
+ */
+static int sd_cdl_enable(struct scsi_disk *sdkp, bool enable)
+{
+ struct scsi_device *sdp = sdkp->device;
+ struct scsi_mode_data data;
+ struct scsi_sense_hdr sshdr;
+ struct scsi_vpd *vpd;
+ bool is_ata = false;
+ char buf[64];
+ int ret;
+
+ rcu_read_lock();
+ vpd = rcu_dereference(sdp->vpd_pg89);
+ if (vpd)
+ is_ata = true;
+ rcu_read_unlock();
+
+ /*
+ * For ATA devices, CDL needs to be enabled with a SET FEATURES command.
+ */
+ if (is_ata) {
+ char *buf_data;
+ int len;
+
+ ret = scsi_mode_sense(sdp, 0x08, 0x0a, 0xf2, buf, sizeof(buf),
+ SD_TIMEOUT, sdkp->max_retries, &data,
+ NULL);
+ if (ret)
+ return -EINVAL;
+
