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Diffstat (limited to 'drivers/scsi/sd.c')
-rw-r--r--drivers/scsi/sd.c107
1 files changed, 107 insertions, 0 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 9093c7261f33..255da53e5a01 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -264,6 +264,15 @@ sd_show_app_tag_own(struct device *dev, struct device_attribute *attr,
return snprintf(buf, 20, "%u\n", sdkp->ATO);
}
+static ssize_t
+sd_show_thin_provisioning(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+ return snprintf(buf, 20, "%u\n", sdkp->thin_provisioning);
+}
+
static struct device_attribute sd_disk_attrs[] = {
__ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
sd_store_cache_type),
@@ -274,6 +283,7 @@ static struct device_attribute sd_disk_attrs[] = {
sd_store_manage_start_stop),
__ATTR(protection_type, S_IRUGO, sd_show_protection_type, NULL),
__ATTR(app_tag_own, S_IRUGO, sd_show_app_tag_own, NULL),
+ __ATTR(thin_provisioning, S_IRUGO, sd_show_thin_provisioning, NULL),
__ATTR_NULL,
};
@@ -399,6 +409,57 @@ static void sd_prot_op(struct scsi_cmnd *scmd, unsigned int dif)
}
/**
+ * sd_prepare_discard - unmap blocks on thinly provisioned device
+ * @rq: Request to prepare
+ *
+ * Will issue either UNMAP or WRITE SAME(16) depending on preference
+ * indicated by target device.
+ **/
+static int sd_prepare_discard(struct request *rq)
+{
+ struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
+ struct bio *bio = rq->bio;
+ sector_t sector = bio->bi_sector;
+ unsigned int num = bio_sectors(bio);
+
+ if (sdkp->device->sector_size == 4096) {
+ sector >>= 3;
+ num >>= 3;
+ }
+
+ rq->cmd_type = REQ_TYPE_BLOCK_PC;
+ rq->timeout = SD_TIMEOUT;
+
+ memset(rq->cmd, 0, rq->cmd_len);
+
+ if (sdkp->unmap) {
+ char *buf = kmap_atomic(bio_page(bio), KM_USER0);
+
+ rq->cmd[0] = UNMAP;
+ rq->cmd[8] = 24;
+ rq->cmd_len = 10;
+
+ /* Ensure that data length matches payload */
+ rq->__data_len = bio->bi_size = bio->bi_io_vec->bv_len = 24;
+
+ put_unaligned_be16(6 + 16, &buf[0]);
+ put_unaligned_be16(16, &buf[2]);
+ put_unaligned_be64(sector, &buf[8]);
+ put_unaligned_be32(num, &buf[16]);
+
+ kunmap_atomic(buf, KM_USER0);
+ } else {
+ rq->cmd[0] = WRITE_SAME_16;
+ rq->cmd[1] = 0x8; /* UNMAP */
+ put_unaligned_be64(sector, &rq->cmd[2]);
+ put_unaligned_be32(num, &rq->cmd[10]);
+ rq->cmd_len = 16;
+ }
+
+ return BLKPREP_OK;
+}
+
+/**
* sd_init_command - build a scsi (read or write) command from
* information in the request structure.
* @SCpnt: pointer to mid-level's per scsi command structure that
@@ -418,6 +479,13 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
int ret, host_dif;
unsigned char protect;
+ /*
+ * Discard request come in as REQ_TYPE_FS but we turn them into
+ * block PC requests to make life easier.
+ */
+ if (blk_discard_rq(rq))
+ ret = sd_prepare_discard(rq);
+
if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
ret = scsi_setup_blk_pc_cmnd(sdp, rq);
goto out;
@@ -1432,6 +1500,19 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
sd_printk(KERN_NOTICE, sdkp,
"physical block alignment offset: %u\n", alignment);
+ if (buffer[14] & 0x80) { /* TPE */
+ struct request_queue *q = sdp->request_queue;
+
+ sdkp->thin_provisioning = 1;
+ q->limits.discard_granularity = sdkp->hw_sector_size;
+ q->limits.max_discard_sectors = 0xffffffff;
+
+ if (buffer[14] & 0x40) /* TPRZ */
+ q->limits.discard_zeroes_data = 1;
+
+ queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
+ }
+
sdkp->capacity = lba + 1;
return sector_size;
}
@@ -1863,6 +1944,7 @@ void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
*/
static void sd_read_block_limits(struct scsi_disk *sdkp)
{
+ struct request_queue *q = sdkp->disk->queue;
unsigned int sector_sz = sdkp->device->sector_size;
char *buffer;
@@ -1877,6 +1959,31 @@ static void sd_read_block_limits(struct scsi_disk *sdkp)
blk_queue_io_opt(sdkp->disk->queue,
get_unaligned_be32(&buffer[12]) * sector_sz);
+ /* Thin provisioning enabled and page length indicates TP support */
+ if (sdkp->thin_provisioning && buffer[3] == 0x3c) {
+ unsigned int lba_count, desc_count, granularity;
+
+ lba_count = get_unaligned_be32(&buffer[20]);
+ desc_count = get_unaligned_be32(&buffer[24]);
+
+ if (lba_count) {
+ q->limits.max_discard_sectors =
+ lba_count * sector_sz >> 9;
+
+ if (desc_count)
+ sdkp->unmap = 1;
+ }
+
+ granularity = get_unaligned_be32(&buffer[28]);
+
+ if (granularity)
+ q->limits.discard_granularity = granularity * sector_sz;
+
+ if (buffer[32] & 0x80)
+ q->limits.discard_alignment =
+ get_unaligned_be32(&buffer[32]) & ~(1 << 31);
+ }
+
kfree(buffer);
}