diff options
Diffstat (limited to 'mm/swapfile.c')
-rw-r--r-- | mm/swapfile.c | 52 |
1 files changed, 26 insertions, 26 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index 2c33ff456ed5..5871a2aa86a5 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -2132,7 +2132,7 @@ int try_to_unuse(unsigned int type, bool frontswap, swp_entry_t entry; unsigned int i; - if (!si->inuse_pages) + if (!READ_ONCE(si->inuse_pages)) return 0; if (!frontswap) @@ -2148,7 +2148,7 @@ retry: spin_lock(&mmlist_lock); p = &init_mm.mmlist; - while (si->inuse_pages && + while (READ_ONCE(si->inuse_pages) && !signal_pending(current) && (p = p->next) != &init_mm.mmlist) { @@ -2177,7 +2177,7 @@ retry: mmput(prev_mm); i = 0; - while (si->inuse_pages && + while (READ_ONCE(si->inuse_pages) && !signal_pending(current) && (i = find_next_to_unuse(si, i, frontswap)) != 0) { @@ -2219,7 +2219,7 @@ retry: * been preempted after get_swap_page(), temporarily hiding that swap. * It's easy and robust (though cpu-intensive) just to keep retrying. */ - if (si->inuse_pages) { + if (READ_ONCE(si->inuse_pages)) { if (!signal_pending(current)) goto retry; retval = -EINTR; @@ -2797,6 +2797,7 @@ static int swaps_open(struct inode *inode, struct file *file) } static const struct proc_ops swaps_proc_ops = { + .proc_flags = PROC_ENTRY_PERMANENT, .proc_open = swaps_open, .proc_read = seq_read, .proc_lseek = seq_lseek, @@ -2899,10 +2900,6 @@ static int claim_swapfile(struct swap_info_struct *p, struct inode *inode) p->bdev = inode->i_sb->s_bdev; } - inode_lock(inode); - if (IS_SWAPFILE(inode)) - return -EBUSY; - return 0; } @@ -3157,36 +3154,41 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) mapping = swap_file->f_mapping; inode = mapping->host; - /* If S_ISREG(inode->i_mode) will do inode_lock(inode); */ error = claim_swapfile(p, inode); if (unlikely(error)) goto bad_swap; + inode_lock(inode); + if (IS_SWAPFILE(inode)) { + error = -EBUSY; + goto bad_swap_unlock_inode; + } + /* * Read the swap header. */ if (!mapping->a_ops->readpage) { error = -EINVAL; - goto bad_swap; + goto bad_swap_unlock_inode; } page = read_mapping_page(mapping, 0, swap_file); if (IS_ERR(page)) { error = PTR_ERR(page); - goto bad_swap; + goto bad_swap_unlock_inode; } swap_header = kmap(page); maxpages = read_swap_header(p, swap_header, inode); if (unlikely(!maxpages)) { error = -EINVAL; - goto bad_swap; + goto bad_swap_unlock_inode; } /* OK, set up the swap map and apply the bad block list */ swap_map = vzalloc(maxpages); if (!swap_map) { error = -ENOMEM; - goto bad_swap; + goto bad_swap_unlock_inode; } if (bdi_cap_stable_pages_required(inode_to_bdi(inode))) @@ -3211,7 +3213,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) GFP_KERNEL); if (!cluster_info) { error = -ENOMEM; - goto bad_swap; + goto bad_swap_unlock_inode; } for (ci = 0; ci < nr_cluster; ci++) @@ -3220,7 +3222,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) p->percpu_cluster = alloc_percpu(struct percpu_cluster); if (!p->percpu_cluster) { error = -ENOMEM; - goto bad_swap; + goto bad_swap_unlock_inode; } for_each_possible_cpu(cpu) { struct percpu_cluster *cluster; @@ -3234,13 +3236,13 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) error = swap_cgroup_swapon(p->type, maxpages); if (error) - goto bad_swap; + goto bad_swap_unlock_inode; nr_extents = setup_swap_map_and_extents(p, swap_header, swap_map, cluster_info, maxpages, &span); if (unlikely(nr_extents < 0)) { error = nr_extents; - goto bad_swap; + goto bad_swap_unlock_inode; } /* frontswap enabled? set up bit-per-page map for frontswap */ if (IS_ENABLED(CONFIG_FRONTSWAP)) @@ -3280,7 +3282,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) error = init_swap_address_space(p->type, maxpages); if (error) - goto bad_swap; + goto bad_swap_unlock_inode; /* * Flush any pending IO and dirty mappings before we start using this @@ -3290,7 +3292,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) error = inode_drain_writes(inode); if (error) { inode->i_flags &= ~S_SWAPFILE; - goto bad_swap; + goto bad_swap_unlock_inode; } mutex_lock(&swapon_mutex); @@ -3315,6 +3317,8 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) error = 0; goto out; +bad_swap_unlock_inode: + inode_unlock(inode); bad_swap: free_percpu(p->percpu_cluster); p->percpu_cluster = NULL; @@ -3322,6 +3326,7 @@ bad_swap: set_blocksize(p->bdev, p->old_block_size); blkdev_put(p->bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL); } + inode = NULL; destroy_swap_extents(p); swap_cgroup_swapoff(p->type); spin_lock(&swap_lock); @@ -3333,13 +3338,8 @@ bad_swap: kvfree(frontswap_map); if (inced_nr_rotate_swap) atomic_dec(&nr_rotate_swap); - if (swap_file) { - if (inode) { - inode_unlock(inode); - inode = NULL; - } + if (swap_file) filp_close(swap_file, NULL); - } out: if (page && !IS_ERR(page)) { kunmap(page); @@ -3476,7 +3476,7 @@ int swap_duplicate(swp_entry_t entry) * * Called when allocating swap cache for existing swap entry, * This can return error codes. Returns 0 at success. - * -EBUSY means there is a swap cache. + * -EEXIST means there is a swap cache. * Note: return code is different from swap_duplicate(). */ int swapcache_prepare(swp_entry_t entry) |