From e78db4dfb1355a895f7ea50133b702b55b8ed184 Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Thu, 26 Nov 2009 22:46:03 -0500 Subject: libata: Report zeroed read after TRIM and max discard size Our current TRIM payload is a single sector that can accommodate 64 * 65535 blocks being unmapped. Report this value in the Block Limits Maximum Unmap LBA count field. If a storage device supports TRIM and the DRAT and RZAT bits are set, report TPRZ=1 in Read Capacity(16). Signed-off-by: Martin K. Petersen Signed-off-by: Jeff Garzik --- drivers/ata/libata-scsi.c | 12 +++++++++--- include/linux/ata.h | 11 +++++++++++ 2 files changed, 20 insertions(+), 3 deletions(-) diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 340a616d226..e1e186b9dfc 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -2115,8 +2115,10 @@ static unsigned int ata_scsiop_inq_b0(struct ata_scsi_args *args, u8 *rbuf) * that we support some form of unmap - in thise case via WRITE SAME * with the unmap bit set. */ - if (ata_id_has_trim(args->id)) + if (ata_id_has_trim(args->id)) { + put_unaligned_be32(65535 * 512 / 8, &rbuf[20]); put_unaligned_be32(1, &rbuf[28]); + } return 0; } @@ -2411,8 +2413,12 @@ static unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf) rbuf[14] = (lowest_aligned >> 8) & 0x3f; rbuf[15] = lowest_aligned; - if (ata_id_has_trim(args->id)) - rbuf[14] |= 0x80; + if (ata_id_has_trim(args->id)) { + rbuf[14] |= 0x80; /* TPE */ + + if (ata_id_has_zero_after_trim(args->id)) + rbuf[14] |= 0x40; /* TPRZ */ + } } return 0; diff --git a/include/linux/ata.h b/include/linux/ata.h index e2595e877e4..dfa2298bf48 100644 --- a/include/linux/ata.h +++ b/include/linux/ata.h @@ -75,6 +75,7 @@ enum { ATA_ID_EIDE_DMA_TIME = 66, ATA_ID_EIDE_PIO = 67, ATA_ID_EIDE_PIO_IORDY = 68, + ATA_ID_ADDITIONAL_SUPP = 69, ATA_ID_QUEUE_DEPTH = 75, ATA_ID_MAJOR_VER = 80, ATA_ID_COMMAND_SET_1 = 82, @@ -816,6 +817,16 @@ static inline int ata_id_has_trim(const u16 *id) return 0; } +static inline int ata_id_has_zero_after_trim(const u16 *id) +{ + /* DSM supported, deterministic read, and read zero after trim set */ + if (ata_id_has_trim(id) && + (id[ATA_ID_ADDITIONAL_SUPP] & 0x4020) == 0x4020) + return 1; + + return 0; +} + static inline int ata_id_current_chs_valid(const u16 *id) { /* For ATA-1 devices, if the INITIALIZE DEVICE PARAMETERS command -- cgit v1.2.3