diff mbox

[v6,2/2] libata-scsi: avoid repeated calculation of number of TRIM ranges

Message ID 7f727a9fd877b2c16cd8799e1da8be71f5b8eaf3.1468354842.git.tom.ty89@gmail.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Tom Yan July 12, 2016, 8:31 p.m. UTC 
From: Tom Yan <tom.ty89@gmail.com>

Currently libata statically allows only 1-block (512-byte) payload
for each TRIM command. Each payload can carry 64 TRIM ranges since
each range requires 8 bytes.

It is silly to keep doing the calculation (512 / 8) in different
places. Hence, define the new ATA_MAX_TRIM_RNUM for the result.

Signed-off-by: Tom Yan <tom.ty89@gmail.com>

Comments

Tejun Heo July 12, 2016, 8:38 p.m. UTC | #1 
On Wed, Jul 13, 2016 at 04:31:23AM +0800, tom.ty89@gmail.com wrote:
> From: Tom Yan <tom.ty89@gmail.com>
> 
> Currently libata statically allows only 1-block (512-byte) payload
> for each TRIM command. Each payload can carry 64 TRIM ranges since
> each range requires 8 bytes.
> 
> It is silly to keep doing the calculation (512 / 8) in different
> places. Hence, define the new ATA_MAX_TRIM_RNUM for the result.
> 
> Signed-off-by: Tom Yan <tom.ty89@gmail.com>

Applied 1-2 to libata/for-4.8.

Thanks.
diff mbox

Patch

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 392aebb..62fb5b9 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -2314,7 +2314,7 @@  static unsigned int ata_scsiop_inq_b0(struct ata_scsi_args *args, u8 *rbuf)
 	 * with the unmap bit set.
 	 */
 	if (ata_id_has_trim(args->id)) {
-		put_unaligned_be64(65535 * 512 / 8, &rbuf[36]);
+		put_unaligned_be64(65535 * ATA_MAX_TRIM_RNUM, &rbuf[36]);
 		put_unaligned_be32(1, &rbuf[28]);
 	}
 
@@ -3306,8 +3306,8 @@  static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
 
 	buf = page_address(sg_page(scsi_sglist(scmd)));
 
-	if (n_block <= 65535 * 512 / 8) {
-		size = ata_set_lba_range_entries(buf, 512, block, n_block);
+	if (n_block <= 65535 * ATA_MAX_TRIM_RNUM) {
+		size = ata_set_lba_range_entries(buf, ATA_MAX_TRIM_RNUM, block, n_block);
 	} else {
 		fp = 2;
 		goto invalid_fld;
diff --git a/include/linux/ata.h b/include/linux/ata.h
index 99346be..2d2d072 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -48,6 +48,7 @@  enum {
 	ATA_MAX_SECTORS_1024    = 1024,
 	ATA_MAX_SECTORS_LBA48	= 65535,/* TODO: 65536? */
 	ATA_MAX_SECTORS_TAPE	= 65535,
+	ATA_MAX_TRIM_RNUM	= 64,	/* 512-byte payload / (6-byte LBA + 2-byte range per entry) */
 
 	ATA_ID_WORDS		= 256,
 	ATA_ID_CONFIG		= 0,
@@ -1066,12 +1067,12 @@  static inline void ata_id_to_hd_driveid(u16 *id)
  * TO NV CACHE PINNED SET.
  */
 static inline unsigned ata_set_lba_range_entries(void *_buffer,
-		unsigned buf_size, u64 sector, unsigned long count)
+		unsigned num, u64 sector, unsigned long count)
 {
 	__le64 *buffer = _buffer;
 	unsigned i = 0, used_bytes;
 
-	while (i < buf_size / 8 ) { /* 6-byte LBA + 2-byte range per entry */
+	while (i < num) {
 		u64 entry = sector |
 			((u64)(count > 0xffff ? 0xffff : count) << 48);
 		buffer[i++] = __cpu_to_le64(entry);