From: Mike Christie <mchristi@xxxxxxxxxx> max_discard_sectors only 32bits, and some non scsi backend devices will set this to the max 0xffffffff, so we can end up overflowing during the max_unmap_lba_count calculation. This fixes a regression caused by my patch: commit 8a9ebe717a133ba7bc90b06047f43cc6b8bcb8b3 Author: Mike Christie <mchristi@xxxxxxxxxx> Date: Mon Jan 18 14:09:27 2016 -0600 target: Fix WRITE_SAME/DISCARD conversion to linux 512b sectors which can result in extra discards being sent to due the overflow causing max_unmap_lba_count to be smaller than what the backing device can actually support. Signed-off-by: Mike Christie <mchristi@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/target/target_core_device.c | 8 +++++--- drivers/target/target_core_file.c | 3 +-- drivers/target/target_core_iblock.c | 3 +-- include/target/target_core_backend.h | 2 +- 4 files changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index a4046ca..6b42348 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -821,13 +821,15 @@ struct se_device *target_alloc_device(struct se_hba *hba, const char *name) * in ATA and we need to set TPE=1 */ bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib, - struct request_queue *q, int block_size) + struct request_queue *q) { + int block_size = queue_logical_block_size(q); + if (!blk_queue_discard(q)) return false; - attrib->max_unmap_lba_count = (q->limits.max_discard_sectors << 9) / - block_size; + attrib->max_unmap_lba_count = + q->limits.max_discard_sectors >> (ilog2(block_size) - 9); /* * Currently hardcoded to 1 in Linux/SCSI code.. */ diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c index 75f0f08..7929186 100644 --- a/drivers/target/target_core_file.c +++ b/drivers/target/target_core_file.c @@ -161,8 +161,7 @@ static int fd_configure_device(struct se_device *dev) dev_size, div_u64(dev_size, fd_dev->fd_block_size), fd_dev->fd_block_size); - if (target_configure_unmap_from_queue(&dev->dev_attrib, q, - fd_dev->fd_block_size)) + if (target_configure_unmap_from_queue(&dev->dev_attrib, q)) pr_debug("IFILE: BLOCK Discard support available," " disabled by default\n"); /* diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c index 7c4efb4..2077bc2 100644 --- a/drivers/target/target_core_iblock.c +++ b/drivers/target/target_core_iblock.c @@ -121,8 +121,7 @@ static int iblock_configure_device(struct se_device *dev) dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q); dev->dev_attrib.hw_queue_depth = q->nr_requests; - if (target_configure_unmap_from_queue(&dev->dev_attrib, q, - dev->dev_attrib.hw_block_size)) + if (target_configure_unmap_from_queue(&dev->dev_attrib, q)) pr_debug("IBLOCK: BLOCK Discard support available," " disabled by default\n"); diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h index d8ab510..f6f3bc5 100644 --- a/include/target/target_core_backend.h +++ b/include/target/target_core_backend.h @@ -95,6 +95,6 @@ sense_reason_t passthrough_parse_cdb(struct se_cmd *cmd, bool target_sense_desc_format(struct se_device *dev); sector_t target_to_linux_sector(struct se_device *dev, sector_t lb); bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib, - struct request_queue *q, int block_size); + struct request_queue *q); #endif /* TARGET_CORE_BACKEND_H */ -- 2.7.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html