diff options
| author | Christoph Hellwig <hch@lst.de> | 2020-09-21 09:19:56 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-09-23 18:43:19 +0200 |
| commit | 21bd900572f3708e281ea25f051fc92462eb1193 (patch) | |
| tree | 6a35266ebc9c5c5c49d7245861a80f391900934c /mm/swapfile.c | |
| parent | PM: rewrite is_hibernate_resume_dev to not require an inode (diff) | |
| download | linux-21bd900572f3708e281ea25f051fc92462eb1193.tar.xz linux-21bd900572f3708e281ea25f051fc92462eb1193.zip | |
mm: split swap_type_of
swap_type_of is used for two entirely different purposes:
(1) check what swap type a given device/offset corresponds to
(2) find the first available swap device that can be written to
Mixing both in a single function creates an unreadable mess. Create two
separate functions instead, and switch both to pass a dev_t instead of
a struct block_device to further simplify the code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'mm/swapfile.c')
| -rw-r--r-- | mm/swapfile.c | 39 |
1 files changed, 21 insertions, 18 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index 7438c4affc75..b90f86920743 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1801,13 +1801,12 @@ int free_swap_and_cache(swp_entry_t entry) * * This is needed for the suspend to disk (aka swsusp). */ -int swap_type_of(dev_t device, sector_t offset, struct block_device **bdev_p) +int swap_type_of(dev_t device, sector_t offset) { - struct block_device *bdev = NULL; int type; - if (device) - bdev = bdget(device); + if (!device) + return -1; spin_lock(&swap_lock); for (type = 0; type < nr_swapfiles; type++) { @@ -1816,30 +1815,34 @@ int swap_type_of(dev_t device, sector_t offset, struct block_device **bdev_p) if (!(sis->flags & SWP_WRITEOK)) continue; - if (!bdev) { - if (bdev_p) - *bdev_p = bdgrab(sis->bdev); - - spin_unlock(&swap_lock); - return type; - } - if (bdev == sis->bdev) { + if (device == sis->bdev->bd_dev) { struct swap_extent *se = first_se(sis); if (se->start_block == offset) { - if (bdev_p) - *bdev_p = bdgrab(sis->bdev); - spin_unlock(&swap_lock); - bdput(bdev); return type; } } } spin_unlock(&swap_lock); - if (bdev) - bdput(bdev); + return -ENODEV; +} +int find_first_swap(dev_t *device) +{ + int type; + + spin_lock(&swap_lock); + for (type = 0; type < nr_swapfiles; type++) { + struct swap_info_struct *sis = swap_info[type]; + + if (!(sis->flags & SWP_WRITEOK)) + continue; + *device = sis->bdev->bd_dev; + spin_unlock(&swap_lock); + return type; + } + spin_unlock(&swap_lock); return -ENODEV; } |