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 --- include/linux/ata.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include/linux/ata.h') diff --git a/include/linux/ata.h b/include/linux/ata.h index e2595e877e44..dfa2298bf488 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 v1.2.3-59-g8ed1b