Commit 2983860c authored by Tom Yan's avatar Tom Yan Committed by Tejun Heo
Browse files

libata-scsi: avoid repeated calculation of number of TRIM ranges 



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: default avatarTom Yan <tom.ty89@gmail.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 5c79097a

drivers/ata/libata-scsi.c

+3 −3
Original line number Diff line number Diff line
@@ -2319,7 +2319,7 @@ 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]);

	}
@@ -3311,8 +3311,8 @@ 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;

include/linux/ata.h

+3 −2
Original line number Diff line number Diff line
@@ -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,
@@ -1069,12 +1070,12 @@ 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);

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