diff options
Diffstat (limited to 'mm/swapfile.c')
| -rw-r--r-- | mm/swapfile.c | 54 |
1 files changed, 35 insertions, 19 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index 6fe0cc2553..4919423cce 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -737,8 +737,6 @@ static void swap_range_free(struct swap_info_struct *si, unsigned long offset, if (was_full && (si->flags & SWP_WRITEOK)) add_to_avail_list(si); } - atomic_long_add(nr_entries, &nr_swap_pages); - WRITE_ONCE(si->inuse_pages, si->inuse_pages - nr_entries); if (si->flags & SWP_BLKDEV) swap_slot_free_notify = si->bdev->bd_disk->fops->swap_slot_free_notify; @@ -746,12 +744,19 @@ static void swap_range_free(struct swap_info_struct *si, unsigned long offset, swap_slot_free_notify = NULL; while (offset <= end) { arch_swap_invalidate_page(si->type, offset); - zswap_invalidate(si->type, offset); if (swap_slot_free_notify) swap_slot_free_notify(si->bdev, offset); offset++; } clear_shadow_from_swap_cache(si->type, begin, end); + + /* + * Make sure that try_to_unuse() observes si->inuse_pages reaching 0 + * only after the above cleanups are done. + */ + smp_wmb(); + atomic_long_add(nr_entries, &nr_swap_pages); + WRITE_ONCE(si->inuse_pages, si->inuse_pages - nr_entries); } static void set_cluster_next(struct swap_info_struct *si, unsigned long next) @@ -2060,7 +2065,7 @@ static int try_to_unuse(unsigned int type) unsigned int i; if (!READ_ONCE(si->inuse_pages)) - return 0; + goto success; retry: retval = shmem_unuse(type); @@ -2141,6 +2146,12 @@ retry: return -EINTR; } +success: + /* + * Make sure that further cleanups after try_to_unuse() returns happen + * after swap_range_free() reduces si->inuse_pages to 0. + */ + smp_mb(); return 0; } @@ -2359,8 +2370,6 @@ static void enable_swap_info(struct swap_info_struct *p, int prio, unsigned char *swap_map, struct swap_cluster_info *cluster_info) { - zswap_swapon(p->type); - spin_lock(&swap_lock); spin_lock(&p->lock); setup_swap_info(p, prio, swap_map, cluster_info); @@ -2543,10 +2552,10 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile) exit_swap_address_space(p->type); inode = mapping->host; - if (p->bdev_handle) { + if (p->bdev_file) { set_blocksize(p->bdev, old_block_size); - bdev_release(p->bdev_handle); - p->bdev_handle = NULL; + fput(p->bdev_file); + p->bdev_file = NULL; } inode_lock(inode); @@ -2776,14 +2785,14 @@ static int claim_swapfile(struct swap_info_struct *p, struct inode *inode) int error; if (S_ISBLK(inode->i_mode)) { - p->bdev_handle = bdev_open_by_dev(inode->i_rdev, + p->bdev_file = bdev_file_open_by_dev(inode->i_rdev, BLK_OPEN_READ | BLK_OPEN_WRITE, p, NULL); - if (IS_ERR(p->bdev_handle)) { - error = PTR_ERR(p->bdev_handle); - p->bdev_handle = NULL; + if (IS_ERR(p->bdev_file)) { + error = PTR_ERR(p->bdev_file); + p->bdev_file = NULL; return error; } - p->bdev = p->bdev_handle->bdev; + p->bdev = file_bdev(p->bdev_file); p->old_block_size = block_size(p->bdev); error = set_blocksize(p->bdev, PAGE_SIZE); if (error < 0) @@ -3178,6 +3187,10 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) if (error) goto bad_swap_unlock_inode; + error = zswap_swapon(p->type, maxpages); + if (error) + goto free_swap_address_space; + /* * Flush any pending IO and dirty mappings before we start using this * swap device. @@ -3186,7 +3199,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) error = inode_drain_writes(inode); if (error) { inode->i_flags &= ~S_SWAPFILE; - goto free_swap_address_space; + goto free_swap_zswap; } mutex_lock(&swapon_mutex); @@ -3210,6 +3223,8 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) error = 0; goto out; +free_swap_zswap: + zswap_swapoff(p->type); free_swap_address_space: exit_swap_address_space(p->type); bad_swap_unlock_inode: @@ -3219,10 +3234,10 @@ bad_swap: p->percpu_cluster = NULL; free_percpu(p->cluster_next_cpu); p->cluster_next_cpu = NULL; - if (p->bdev_handle) { + if (p->bdev_file) { set_blocksize(p->bdev, p->old_block_size); - bdev_release(p->bdev_handle); - p->bdev_handle = NULL; + fput(p->bdev_file); + p->bdev_file = NULL; } inode = NULL; destroy_swap_extents(p); @@ -3331,7 +3346,8 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage) } else err = -ENOENT; /* unused swap entry */ - WRITE_ONCE(p->swap_map[offset], count | has_cache); + if (!err) + WRITE_ONCE(p->swap_map[offset], count | has_cache); unlock_out: unlock_cluster_or_swap_info(p, ci); |