diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
index ec3764c8f3f16..db16c19e05c4e 100644
--- a/drivers/scsi/sd_zbc.c
+++ b/drivers/scsi/sd_zbc.c
@@ -9,6 +9,8 @@
*/
#include <linux/blkdev.h>
+#include <linux/vmalloc.h>
+#include <linux/sched/mm.h>
#include <asm/unaligned.h>
@@ -50,7 +52,7 @@ static void sd_zbc_parse_report(struct scsi_disk *sdkp, u8 *buf,
/**
* sd_zbc_do_report_zones - Issue a REPORT ZONES scsi command.
* @sdkp: The target disk
- * @buf: Buffer to use for the reply
+ * @buf: vmalloc-ed buffer to use for the reply
* @buflen: the buffer size
* @lba: Start LBA of the report
* @partial: Do partial report
@@ -79,7 +81,6 @@ static int sd_zbc_do_report_zones(struct scsi_disk *sdkp, unsigned char *buf,
put_unaligned_be32(buflen, &cmd[10]);
if (partial)
cmd[14] = ZBC_REPORT_ZONE_PARTIAL;
- memset(buf, 0, buflen);
result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
buf, buflen, &sshdr,
@@ -103,6 +104,53 @@ static int sd_zbc_do_report_zones(struct scsi_disk *sdkp, unsigned char *buf,
return 0;
}
+/*
+ * Maximum number of zones to get with one report zones command.
+ */
+#define SD_ZBC_REPORT_MAX_ZONES 8192U
+
+/**
+ * Allocate a buffer for report zones reply.
+ * @sdkp: The target disk
+ * @nr_zones: Maximum number of zones to report
+ * @buflen: Size of the buffer allocated
+ *
+ * Try to allocate a reply buffer for the number of requested zones.
+ * The size of the buffer allocated may be smaller than requested to
+ * satify the device constraint (max_hw_sectors, max_segments, etc).
+ *
+ * Return the address of the allocated buffer and update @buflen with
+ * the size of the allocated buffer.
+ */
+static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp,
+ unsigned int nr_zones, size_t *buflen)
+{
+ struct request_queue *q = sdkp->disk->queue;
+ size_t bufsize;
+ void *buf;
+
+ /*
+ * Report zone buffer size should be at most 64B times the number of
+ * zones requested plus the 64B reply header, but should be at least
+ * SECTOR_SIZE for ATA devices.
+ * Make sure that this size does not exceed the hardware capabilities.
+ * Furthermore, since the report zone command cannot be split, make
+ * sure that the allocated buffer can always be mapped by limiting the
+ * number of pages allocated to the HBA max segments limit.
+ */
+ nr_zones = min(nr_zones, SD_ZBC_REPORT_MAX_ZONES);
+ bufsize = roundup((nr_zones + 1) * 64, 512);
+ bufsize = min_t(size_t, bufsize,
+ queue_max_hw_sectors(q) << SECTOR_SHIFT);
+ bufsize = min_t(size_t, bufsize, queue_max_segments(q) << PAGE_SHIFT);
+
+ buf = vzalloc(bufsize);
+ if (buf)
+ *buflen = bufsize;
+
+ return buf;
+}
+
/**
* sd_zbc_report_zones - Disk report zones operation.
* @disk: The target disk
@@ -116,30 +164,23 @@ int sd_zbc_report_zones(struct gendisk *disk, sector_t sector,
struct blk_zone *zones, unsigned int *nr_zones)
{
struct scsi_disk *sdkp = scsi_disk(disk);
- unsigned int i, buflen, nrz = *nr_zones;
+ unsigned int i, nrz = *nr_zones;
unsigned char *buf;
- size_t offset = 0;
+ size_t buflen = 0, offset = 0;
int ret = 0;
if (!sd_is_zoned(sdkp))
/* Not a zoned device */
return -EOPNOTSUPP;
- /*
- * Get a reply buffer for the number of requested zones plus a header,
- * without exceeding the device maximum command size. For ATA disks,
- * buffers must be aligned to 512B.
- */
- buflen = min(queue_max_hw_sectors(disk->queue) << 9,
- roundup((nrz + 1) * 64, 512));
- buf = kmalloc(buflen, GFP_KERNEL);
+ buf = sd_zbc_alloc_report_buffer(sdkp, nrz, &buflen);
if (!buf)
return -ENOMEM;
ret = sd_zbc_do_report_zones(sdkp, buf, buflen,
sectors_to_logical(sdkp->device, sector), true);
if (ret)
- goto out_free_buf;
+ goto out;
nrz = min(nrz, get_unaligned_be32(&buf[0]) / 64);
for (i = 0; i < nrz; i++) {
@@ -150,8 +191,8 @@ int sd_zbc_report_zones(struct gendisk *disk, sector_t sector,
*nr_zones = nrz;
-out_free_buf:
- kfree(buf);
+out:
+ kvfree(buf);
return ret;
}
@@ -285,8 +326,6 @@ static int sd_zbc_check_zoned_characteristics(struct scsi_disk *sdkp,
return 0;
}
-#define SD_ZBC_BUF_SIZE 131072U
-
/**
* sd_zbc_check_zones - Check the device capacity and zone sizes
* @sdkp: Target disk
@@ -302,22 +341,28 @@ static int sd_zbc_check_zoned_characteristics(struct scsi_disk *sdkp,
*/
static int sd_zbc_check_zones(struct scsi_disk *sdkp, u32 *zblocks)
{
+ size_t bufsize, buflen;
+ unsigned int noio_flag;
u64 zone_blocks = 0;
sector_t max_lba, block = 0;
unsigned char *buf;
unsigned char *rec;
- unsigned int buf_len;
- unsigned int list_length;
int ret;
u8 same;
+ /* Do all memory allocations as if GFP_NOIO was specified */
+ noio_flag = memalloc_noio_save();
+
/* Get a buffer */
- buf = kmalloc(SD_ZBC_BUF_SIZE, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
+ buf = sd_zbc_alloc_report_buffer(sdkp, SD_ZBC_REPORT_MAX_ZONES,
+ &bufsize);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto out;
+ }
/* Do a report zone to get max_lba and the same field */
- ret = sd_zbc_do_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE, 0, false);
+ ret = sd_zbc_do_report_zones(sdkp, buf, bufsize, 0, false);
if (ret)
goto out_free;
@@ -353,12 +398,12 @@ static int sd_zbc_check_zones(struct scsi_disk *sdkp, u32 *zblocks)
do {
/* Parse REPORT ZONES header */
- list_length = get_unaligned_be32(&buf[0]) + 64;
+ buflen = min_t(size_t, get_unaligned_be32(&buf[0]) + 64,
+ bufsize);
rec = buf + 64;
- buf_len = min(list_length, SD_ZBC_BUF_SIZE);
/* Parse zone descriptors */
- while (rec < buf + buf_len) {
+ while (rec < buf + buflen) {
u64 this_zone_blocks = get_unaligned_be64(&rec[8]);
if (zone_blocks == 0) {
@@ -374,8 +419,8 @@ static int sd_zbc_check_zones(struct scsi_disk *sdkp, u32 *zblocks)
}
if (block < sdkp->capacity) {
- ret = sd_zbc_do_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE,
- block, true);
+ ret = sd_zbc_do_report_zones(sdkp, buf, bufsize, block,
+ true);
if (ret)
goto out_free;
}
@@ -406,7 +451,8 @@ static int sd_zbc_check_zones(struct scsi_disk *sdkp, u32 *zblocks)
}
out_free:
- kfree(buf);
+ memalloc_noio_restore(noio_flag);
+ kvfree(buf);
return ret;
}