diff options
Diffstat (limited to 'target/linux/generic/hack-5.4/551-loop-Better-discard-support-for-block-devices.patch')
| -rw-r--r-- | target/linux/generic/hack-5.4/551-loop-Better-discard-support-for-block-devices.patch | 101 |
1 files changed, 0 insertions, 101 deletions
diff --git a/target/linux/generic/hack-5.4/551-loop-Better-discard-support-for-block-devices.patch b/target/linux/generic/hack-5.4/551-loop-Better-discard-support-for-block-devices.patch deleted file mode 100644 index 38091290aa..0000000000 --- a/target/linux/generic/hack-5.4/551-loop-Better-discard-support-for-block-devices.patch +++ /dev/null @@ -1,101 +0,0 @@ -From 3117c3f45edbcc269baaebd3d13f39b7bf884aa6 Mon Sep 17 00:00:00 2001 -From: Evan Green <evgreen@chromium.org> -Date: Thu, 14 Nov 2019 15:50:08 -0800 -Subject: loop: Better discard support for block devices - -If the backing device for a loop device is itself a block device, -then mirror the "write zeroes" capabilities of the underlying -block device into the loop device. Copy this capability into both -max_write_zeroes_sectors and max_discard_sectors of the loop device. - -The reason for this is that REQ_OP_DISCARD on a loop device translates -into blkdev_issue_zeroout(), rather than blkdev_issue_discard(). This -presents a consistent interface for loop devices (that discarded data -is zeroed), regardless of the backing device type of the loop device. -There should be no behavior change for loop devices backed by regular -files. - -This change fixes blktest block/003, and removes an extraneous -error print in block/013 when testing on a loop device backed -by a block device that does not support discard. - -Signed-off-by: Evan Green <evgreen@chromium.org> -Reviewed-by: Gwendal Grignou <gwendal@chromium.org> -Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> ---- - drivers/block/loop.c | 40 +++++++++++++++++++++++++++++----------- - 1 file changed, 29 insertions(+), 11 deletions(-) - ---- a/drivers/block/loop.c -+++ b/drivers/block/loop.c -@@ -427,11 +427,12 @@ static int lo_fallocate(struct loop_devi - * information. - */ - struct file *file = lo->lo_backing_file; -+ struct request_queue *q = lo->lo_queue; - int ret; - - mode |= FALLOC_FL_KEEP_SIZE; - -- if ((!file->f_op->fallocate) || lo->lo_encrypt_key_size) { -+ if (!blk_queue_discard(q)) { - ret = -EOPNOTSUPP; - goto out; - } -@@ -862,6 +863,21 @@ static void loop_config_discard(struct l - struct file *file = lo->lo_backing_file; - struct inode *inode = file->f_mapping->host; - struct request_queue *q = lo->lo_queue; -+ struct request_queue *backingq; -+ -+ /* -+ * If the backing device is a block device, mirror its zeroing -+ * capability. REQ_OP_DISCARD translates to a zero-out even when backed -+ * by block devices to keep consistent behavior with file-backed loop -+ * devices. -+ */ -+ if (S_ISBLK(inode->i_mode) && !lo->lo_encrypt_key_size) { -+ backingq = bdev_get_queue(inode->i_bdev); -+ blk_queue_max_discard_sectors(q, -+ backingq->limits.max_write_zeroes_sectors); -+ -+ blk_queue_max_write_zeroes_sectors(q, -+ backingq->limits.max_write_zeroes_sectors); - - /* - * We use punch hole to reclaim the free space used by the -@@ -869,22 +885,24 @@ static void loop_config_discard(struct l - * encryption is enabled, because it may give an attacker - * useful information. - */ -- if ((!file->f_op->fallocate) || -- lo->lo_encrypt_key_size) { -+ } else if ((!file->f_op->fallocate) || lo->lo_encrypt_key_size) { - q->limits.discard_granularity = 0; - q->limits.discard_alignment = 0; - blk_queue_max_discard_sectors(q, 0); - blk_queue_max_write_zeroes_sectors(q, 0); -- blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q); -- return; -- } - -- q->limits.discard_granularity = inode->i_sb->s_blocksize; -- q->limits.discard_alignment = 0; -+ } else { -+ q->limits.discard_granularity = inode->i_sb->s_blocksize; -+ q->limits.discard_alignment = 0; - -- blk_queue_max_discard_sectors(q, UINT_MAX >> 9); -- blk_queue_max_write_zeroes_sectors(q, UINT_MAX >> 9); -- blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); -+ blk_queue_max_discard_sectors(q, UINT_MAX >> 9); -+ blk_queue_max_write_zeroes_sectors(q, UINT_MAX >> 9); -+ } -+ -+ if (q->limits.max_write_zeroes_sectors) -+ blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); -+ else -+ blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q); - } - - static void loop_unprepare_queue(struct loop_device *lo) |