Initialize the seq_zone_bitmap and nr_zones fields of the disk request
queue on disk revalidate. As the seq_zone_bitmap allocation is
identical to the allocation of the zone write lock bitmap, introduce
the helper sd_zbc_alloc_zone_bitmap(). Using this helper, wait for the
disk capacity and number of zones to stabilize on the second
revalidation pass to allocate and initialize the bitmaps.
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx>
---
drivers/scsi/sd_zbc.c | 138 ++++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 133 insertions(+), 5 deletions(-)
diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
index 27793b9f54c0..4ccb20074cb3 100644
--- a/drivers/scsi/sd_zbc.c
+++ b/drivers/scsi/sd_zbc.c
@@ -586,8 +586,121 @@ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp)
return 0;
}
+/**
+ * sd_zbc_alloc_zone_bitmap - Allocate a zone bitmap (one bit per zone).
+ * @sdkp: The disk of the bitmap
+ */
+static inline unsigned long *sd_zbc_alloc_zone_bitmap(struct scsi_disk *sdkp)
+{
+ struct request_queue *q = sdkp->disk->queue;
+
+ return kzalloc_node(BITS_TO_LONGS(sdkp->nr_zones)
+ * sizeof(unsigned long),
+ GFP_KERNEL, q->node);
+}
+
+/**
+ * sd_zbc_get_seq_zones - Parse report zones reply to identify sequential zones
+ * @sdkp: disk used
+ * @buf: report reply buffer
+ * @seq_zone_bitamp: bitmap of sequential zones to set
+ *
+ * Parse reported zone descriptors in @buf to identify sequential zones and
+ * set the reported zone bit in @seq_zone_bitmap accordingly.
+ * Since read-only and offline zones cannot be written, do not
+ * mark them as sequential in the bitmap.
+ * Return the LBA after the last zone reported.
+ */
+static sector_t sd_zbc_get_seq_zones(struct scsi_disk *sdkp, unsigned char *buf,
+ unsigned int buflen,
+ unsigned long *seq_zone_bitmap)
+{
+ sector_t lba, next_lba = sdkp->capacity;
+ unsigned int buf_len, list_length;
+ unsigned char *rec;
+ u8 type, cond;
+
+ list_length = get_unaligned_be32(&buf[0]) + 64;
+ buf_len = min(list_length, buflen);
+ rec = buf + 64;
+
+ while (rec < buf + buf_len) {
+ type = rec[0] & 0x0f;
+ cond = (rec[1] >> 4) & 0xf;
+ lba = get_unaligned_be64(&rec[16]);
+ if (type != ZBC_ZONE_TYPE_CONV &&
+ cond != ZBC_ZONE_COND_READONLY &&
+ cond != ZBC_ZONE_COND_OFFLINE)
+ set_bit(lba >> sdkp->zone_shift, seq_zone_bitmap);
+ next_lba = lba + get_unaligned_be64(&rec[8]);
+ rec += 64;
+ }
+
+ return next_lba;
+}
+
+/**
+ * sd_zbc_setup_seq_zone_bitmap - Initialize the disk seq zone bitmap.
+ * @sdkp: target disk
+ *
+ * Allocate a zone bitmap and initialize it by identifying sequential zones.
+ */
+static int sd_zbc_setup_seq_zone_bitmap(struct scsi_disk *sdkp)
+{
+ struct request_queue *q = sdkp->disk->queue;
+ unsigned long *seq_zone_bitmap;
+ sector_t lba = 0;
+ unsigned char *buf;
+ int ret = -ENOMEM;
+
+ seq_zone_bitmap = sd_zbc_alloc_zone_bitmap(sdkp);
+ if (!seq_zone_bitmap)
+ return -ENOMEM;
+
+ buf = kmalloc(SD_ZBC_BUF_SIZE, GFP_KERNEL);
+ if (!buf)
+ goto out;
+
+ while (lba < sdkp->capacity) {
+ ret = sd_zbc_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE, lba);
+ if (ret)
+ goto out;
+ lba = sd_zbc_get_seq_zones(sdkp, buf, SD_ZBC_BUF_SIZE,
+ seq_zone_bitmap);
+ }
+
+ if (lba != sdkp->capacity) {
+ /* Something went wrong */
+ ret = -EIO;
+ }
+
+out:
+ kfree(buf);
+ if (ret) {
+ kfree(seq_zone_bitmap);
+ return ret;
+ }
+
+ q->seq_zone_bitmap = seq_zone_bitmap;
+
+ return 0;
+}
+
+static void sd_zbc_cleanup(struct scsi_disk *sdkp)
+{
+ struct request_queue *q = sdkp->disk->queue;
+
+ kfree(q->seq_zone_bitmap);
+ q->seq_zone_bitmap = NULL;
+
+ kfree(sdkp->zones_wlock);
+ sdkp->zones_wlock = NULL;
+}
+
static int sd_zbc_setup(struct scsi_disk *sdkp)
{
+ struct request_queue *q = sdkp->disk->queue;
+ int ret;
/* READ16/WRITE16 is mandatory for ZBC disks */
sdkp->device->use_16_for_rw = 1;
@@ -599,14 +712,29 @@ static int sd_zbc_setup(struct scsi_disk *sdkp)
sdkp->nr_zones =
round_up(sdkp->capacity, sdkp->zone_blocks) >> sdkp->zone_shift;
+ /*
+ * Wait for the disk capacity to stabilize before
+ * initializing zone related information.
+ */
+ if (sdkp->first_scan)
+ return 0;
+
if (!sdkp->zones_wlock) {
- sdkp->zones_wlock = kcalloc(BITS_TO_LONGS(sdkp->nr_zones),
- sizeof(unsigned long),
- GFP_KERNEL);
+ sdkp->zones_wlock = sd_zbc_alloc_zone_bitmap(sdkp);
if (!sdkp->zones_wlock)
return -ENOMEM;
}
+ if (!q->seq_zone_bitmap) {
+ ret = sd_zbc_setup_seq_zone_bitmap(sdkp);
+ if (ret) {
+ sd_zbc_cleanup(sdkp);
+ return ret;
+ }
+ }
+
+ q->nr_zones = sdkp->nr_zones;
+
return 0;
}
@@ -661,14 +789,14 @@ int sd_zbc_read_zones(struct scsi_disk *sdkp, unsigned char *buf)
err:
sdkp->capacity = 0;
+ sd_zbc_cleanup(sdkp);
return ret;
}
void sd_zbc_remove(struct scsi_disk *sdkp)
{
- kfree(sdkp->zones_wlock);
- sdkp->zones_wlock = NULL;
+ sd_zbc_cleanup(sdkp);
}
void sd_zbc_print_zones(struct scsi_disk *sdkp)
--
2.13.6
