From ea09bcc9c298d3057270abd78a973fc678d55c4c Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Sat, 23 May 2009 11:43:37 -0400 Subject: [PATCH] sd: Physical block size and alignment support Extract physical block size and lowest aligned LBA from READ CAPACITY(16) response and adjust queue parameters. Report physical block size and alignment when applicable. [jejb: fix up trailing whitespace] Signed-off-by: Martin K. Petersen Signed-off-by: James Bottomley --- drivers/scsi/sd.c | 23 +++++++++++++++++++++-- drivers/scsi/sd.h | 1 + 2 files changed, 22 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 878b17a9af30..a86064b6458d 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1307,6 +1307,7 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp, int sense_valid = 0; int the_result; int retries = 3; + unsigned int alignment; unsigned long long lba; unsigned sector_size; @@ -1358,6 +1359,16 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp, return -EOVERFLOW; } + /* Logical blocks per physical block exponent */ + sdkp->hw_sector_size = (1 << (buffer[13] & 0xf)) * sector_size; + + /* Lowest aligned logical block */ + alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size; + blk_queue_alignment_offset(sdp->request_queue, alignment); + if (alignment && sdkp->first_scan) + sd_printk(KERN_NOTICE, sdkp, + "physical block alignment offset: %u\n", alignment); + sdkp->capacity = lba + 1; return sector_size; } @@ -1409,6 +1420,7 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp, } sdkp->capacity = lba + 1; + sdkp->hw_sector_size = sector_size; return sector_size; } @@ -1521,11 +1533,17 @@ got_data: string_get_size(sz, STRING_UNITS_10, cap_str_10, sizeof(cap_str_10)); - if (sdkp->first_scan || old_capacity != sdkp->capacity) + if (sdkp->first_scan || old_capacity != sdkp->capacity) { sd_printk(KERN_NOTICE, sdkp, - "%llu %d-byte hardware sectors: (%s/%s)\n", + "%llu %d-byte logical blocks: (%s/%s)\n", (unsigned long long)sdkp->capacity, sector_size, cap_str_10, cap_str_2); + + if (sdkp->hw_sector_size != sector_size) + sd_printk(KERN_NOTICE, sdkp, + "%u-byte physical blocks\n", + sdkp->hw_sector_size); + } } /* Rescale capacity to 512-byte units */ @@ -1538,6 +1556,7 @@ got_data: else if (sector_size == 256) sdkp->capacity >>= 1; + blk_queue_physical_block_size(sdp->request_queue, sdkp->hw_sector_size); sdkp->device->sector_size = sector_size; } diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h index 708778cf5f06..8474b5bad3fe 100644 --- a/drivers/scsi/sd.h +++ b/drivers/scsi/sd.h @@ -45,6 +45,7 @@ struct scsi_disk { unsigned int openers; /* protected by BKL for now, yuck */ sector_t capacity; /* size in 512-byte sectors */ u32 index; + unsigned short hw_sector_size; u8 media_present; u8 write_prot; u8 protection_type;/* Data Integrity Field */