From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Christoph Hellwig To: tj@kernel.org, martin.petersen@oracle.com, axboe@kernel.dk Cc: linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, linux-block@vger.kernel.org Subject: [PATCH 2/7] sd: provide a new ata trim provisioning mode Date: Mon, 20 Mar 2017 16:43:14 -0400 Message-Id: <20170320204319.12628-3-hch@lst.de> In-Reply-To: <20170320204319.12628-1-hch@lst.de> References: <20170320204319.12628-1-hch@lst.de> List-ID: This uses a vendor specific command to pass the ATA TRIM payload to libata without having to rewrite it in place. Support for it is indicated by a new flag in struct scsi_device that libata will set in it's slave_configure routine. A second flag indicates if TRIM will reliably zero data. Signed-off-by: Christoph Hellwig --- drivers/scsi/sd.c | 60 +++++++++++++++++++++++++++++++++++++++++++--- drivers/scsi/sd.h | 1 + include/scsi/scsi_device.h | 2 ++ include/scsi/scsi_proto.h | 3 +++ 4 files changed, 63 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index b853f91fb3da..cc8684818305 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -371,6 +371,7 @@ static const char *lbp_mode[] = { [SD_LBP_WS16] = "writesame_16", [SD_LBP_WS10] = "writesame_10", [SD_LBP_ZERO] = "writesame_zero", + [SD_LBP_ATA_TRIM] = "ata_trim", [SD_LBP_DISABLE] = "disabled", }; @@ -411,7 +412,7 @@ provisioning_mode_store(struct device *dev, struct device_attribute *attr, sd_config_discard(sdkp, SD_LBP_ZERO); else if (!strncmp(buf, lbp_mode[SD_LBP_DISABLE], 20)) sd_config_discard(sdkp, SD_LBP_DISABLE); - else + else /* we don't allow manual setting of SD_LBP_ATA_TRIM */ return -EINVAL; return count; @@ -653,7 +654,7 @@ static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode) * lead to data corruption. If LBPRZ is not set, we honor the * device preference. */ - if (sdkp->lbprz) { + if (sdkp->lbprz || sdkp->device->ata_trim) { q->limits.discard_alignment = 0; q->limits.discard_granularity = logical_block_size; } else { @@ -695,6 +696,12 @@ static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode) (u32)SD_MAX_WS10_BLOCKS); q->limits.discard_zeroes_data = 1; break; + + case SD_LBP_ATA_TRIM: + max_blocks = 65535 * (512 / sizeof(__le64)); + if (sdkp->device->ata_trim_zeroes_data) + q->limits.discard_zeroes_data = 1; + break; } blk_queue_max_discard_sectors(q, max_blocks * (logical_block_size >> 9)); @@ -794,6 +801,49 @@ static int sd_setup_write_same10_cmnd(struct scsi_cmnd *cmd, bool unmap) return scsi_init_io(cmd); } +static int sd_setup_ata_trim_cmnd(struct scsi_cmnd *cmd) +{ + struct scsi_device *sdp = cmd->device; + struct request *rq = cmd->request; + u64 sector = blk_rq_pos(rq) >> (ilog2(sdp->sector_size) - 9); + u32 nr_sectors = blk_rq_sectors(rq) >> (ilog2(sdp->sector_size) - 9); + u32 data_len = sdp->sector_size, i; + __le64 *buf; + + rq->special_vec.bv_page = alloc_page(GFP_ATOMIC | __GFP_ZERO); + if (!rq->special_vec.bv_page) + return BLKPREP_DEFER; + rq->special_vec.bv_offset = 0; + rq->special_vec.bv_len = data_len; + rq->rq_flags |= RQF_SPECIAL_PAYLOAD; + + /* + * Use the Linux Vendor Specific TRIM command to pass the TRIM payload + * to libata. + */ + cmd->cmd_len = 10; + cmd->cmnd[0] = LINUX_VS_TRIM; + cmd->cmnd[8] = data_len; + + buf = page_address(rq->special_vec.bv_page); + for (i = 0; i < (data_len >> 3); i++) { + u64 n = min(nr_sectors, 0xffffu); + + buf[i] = cpu_to_le64(sector | (n << 48)); + if (nr_sectors <= 0xffff) + break; + sector += 0xffff; + nr_sectors -= 0xffff; + } + + cmd->allowed = SD_MAX_RETRIES; + cmd->transfersize = data_len; + rq->timeout = SD_TIMEOUT; + scsi_req(rq)->resid_len = data_len; + + return scsi_init_io(cmd); +} + static void sd_config_write_same(struct scsi_disk *sdkp) { struct request_queue *q = sdkp->disk->queue; @@ -1168,6 +1218,8 @@ static int sd_init_command(struct scsi_cmnd *cmd) return sd_setup_write_same10_cmnd(cmd, true); case SD_LBP_ZERO: return sd_setup_write_same10_cmnd(cmd, false); + case SD_LBP_ATA_TRIM: + return sd_setup_ata_trim_cmnd(cmd); default: return BLKPREP_INVALID; } @@ -2739,7 +2791,9 @@ static void sd_read_block_limits(struct scsi_disk *sdkp) sdkp->max_xfer_blocks = get_unaligned_be32(&buffer[8]); sdkp->opt_xfer_blocks = get_unaligned_be32(&buffer[12]); - if (buffer[3] == 0x3c) { + if (sdkp->device->ata_trim) { + sd_config_discard(sdkp, SD_LBP_ATA_TRIM); + } else if (buffer[3] == 0x3c) { unsigned int lba_count, desc_count; sdkp->max_ws_blocks = (u32)get_unaligned_be64(&buffer[36]); diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h index 4dac35e96a75..711d48cea5d7 100644 --- a/drivers/scsi/sd.h +++ b/drivers/scsi/sd.h @@ -56,6 +56,7 @@ enum { SD_LBP_WS16, /* Use WRITE SAME(16) with UNMAP bit */ SD_LBP_WS10, /* Use WRITE SAME(10) with UNMAP bit */ SD_LBP_ZERO, /* Use WRITE SAME(10) with zero payload */ + SD_LBP_ATA_TRIM, /* generate a ATA TRIM payload for libata */ SD_LBP_DISABLE, /* Discard disabled due to failed cmd */ }; diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index 080c7ce9bae8..7b1450b1b130 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -182,6 +182,8 @@ struct scsi_device { unsigned broken_fua:1; /* Don't set FUA bit */ unsigned lun_in_cdb:1; /* Store LUN bits in CDB[1] */ unsigned synchronous_alua:1; /* Synchronous ALUA commands */ + unsigned ata_trim:1; /* use ATA TRIM payload for discard */ + unsigned ata_trim_zeroes_data:1;/* ATA TRIM zeroes discard blocks */ atomic_t disk_events_disable_depth; /* disable depth for disk events */ diff --git a/include/scsi/scsi_proto.h b/include/scsi/scsi_proto.h index 6ba66e01f6df..033b5662a5f5 100644 --- a/include/scsi/scsi_proto.h +++ b/include/scsi/scsi_proto.h @@ -169,6 +169,9 @@ /* Vendor specific CDBs start here */ #define VENDOR_SPECIFIC_CDB 0xc0 +/* used to pass the TRIM payload to libata with rewriting it: */ +#define LINUX_VS_TRIM VENDOR_SPECIFIC_CDB + /* * SCSI command lengths */ -- 2.11.0