Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
loop: remove the use_dio field in struct loop_device
This field duplicate the LO_FLAGS_DIRECT_IO flag in lo_flags. Remove it
to have a single source of truth about using direct I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250110073750.1582447-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
authored by
Christoph Hellwig
and committed by
Jens Axboe
afd69d5c
0cd719aa
+17
-22
+17
-22
drivers/block/loop.c
+17
-22
drivers/block/loop.c
···
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68
struct list_head idle_worker_list;
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struct rb_root worker_tree;
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struct timer_list timer;
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-
bool use_dio;
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bool sysfs_inited;
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72
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struct request_queue *lo_queue;
···
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return true;
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}
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+
/*
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+
* Direct I/O can be enabled either by using an O_DIRECT file descriptor, or by
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+
* passing in the LO_FLAGS_DIRECT_IO flag from userspace. It will be silently
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+
* disabled when the device block size is too small or the offset is unaligned.
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+
*
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* loop_get_status will always report the effective LO_FLAGS_DIRECT_IO flag and
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+
* not the originally passed in one.
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+
*/
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static inline void loop_update_dio(struct loop_device *lo)
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{
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-
bool dio = lo->use_dio || (lo->lo_backing_file->f_flags & O_DIRECT);
201
-
bool use_dio = dio && lo_can_use_dio(lo);
209
+
bool dio_in_use = lo->lo_flags & LO_FLAGS_DIRECT_IO;
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lockdep_assert_held(&lo->lo_mutex);
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WARN_ON_ONCE(lo->lo_state == Lo_bound &&
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lo->lo_queue->mq_freeze_depth == 0);
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-
if (lo->use_dio == use_dio)
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-
return;
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-
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-
/* flush dirty pages before starting to use direct I/O */
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-
if (use_dio)
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-
vfs_fsync(lo->lo_backing_file, 0);
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-
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-
/*
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* The flag of LO_FLAGS_DIRECT_IO is handled similarly with
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-
* LO_FLAGS_READ_ONLY, both are set from kernel, and losetup
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-
* will get updated by ioctl(LOOP_GET_STATUS)
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-
*/
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-
lo->use_dio = use_dio;
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-
if (use_dio)
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+
if (lo->lo_backing_file->f_flags & O_DIRECT)
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lo->lo_flags |= LO_FLAGS_DIRECT_IO;
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-
else
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+
if ((lo->lo_flags & LO_FLAGS_DIRECT_IO) && !lo_can_use_dio(lo))
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lo->lo_flags &= ~LO_FLAGS_DIRECT_IO;
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+
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+
/* flush dirty pages before starting to issue direct I/O */
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+
if ((lo->lo_flags & LO_FLAGS_DIRECT_IO) && !dio_in_use)
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+
vfs_fsync(lo->lo_backing_file, 0);
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}
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/**
···
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disk_force_media_change(lo->lo_disk);
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set_disk_ro(lo->lo_disk, (lo->lo_flags & LO_FLAGS_READ_ONLY) != 0);
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-
lo->use_dio = lo->lo_flags & LO_FLAGS_DIRECT_IO;
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lo->lo_device = bdev;
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lo->lo_backing_file = file;
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lo->old_gfp_mask = mapping_gfp_mask(mapping);
···
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if (lo->lo_state != Lo_bound)
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return -ENXIO;
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-
if (use_dio == lo->use_dio)
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+
if (use_dio == !!(lo->lo_flags & LO_FLAGS_DIRECT_IO))
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return 0;
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if (use_dio) {
···
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}
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blk_mq_freeze_queue(lo->lo_queue);
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-
lo->use_dio = use_dio;
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if (use_dio)
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lo->lo_flags |= LO_FLAGS_DIRECT_IO;
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else
···
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cmd->use_aio = false;
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break;
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default:
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-
cmd->use_aio = lo->use_dio;
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+
cmd->use_aio = lo->lo_flags & LO_FLAGS_DIRECT_IO;
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break;
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}
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