diff options
| author | Hugh Dickins <hugh@veritas.com> | 2005-09-03 15:54:32 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@evo.osdl.org> | 2005-09-05 00:05:40 -0700 |
| commit | e2244ec2efa4ee1edf391d0001d314933e2b2974 (patch) | |
| tree | c9e43f9b6e11ce41d976025c6f9d94c273521132 /mm/swapfile.c | |
| parent | b0d9bcd4bb79a7834f8492f2ae5c2655a551f23d (diff) | |
| download | lwn-e2244ec2efa4ee1edf391d0001d314933e2b2974.tar.gz lwn-e2244ec2efa4ee1edf391d0001d314933e2b2974.zip | |
[PATCH] swap: correct swapfile nr_good_pages
If a regular swapfile lies on a filesystem whose blocksize is less than
PAGE_SIZE, then setup_swap_extents may have to cut the number of usable swap
pages; but sys_swapon's nr_good_pages was not expecting that. Also,
setup_swap_extents takes no account of badpages listed in the swap header: not
worth doing so, but ensure nr_badpages is 0 for a regular swapfile.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm/swapfile.c')
| -rw-r--r-- | mm/swapfile.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index 9f46d83b4ece..5ac5333f37a0 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1008,8 +1008,9 @@ reprobe: } ret = 0; if (page_no == 0) - ret = -EINVAL; + page_no = 1; /* force Empty message */ sis->max = page_no; + sis->pages = page_no - 1; sis->highest_bit = page_no - 1; done: sis->curr_swap_extent = list_entry(sis->extent_list.prev, @@ -1446,6 +1447,10 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) p->highest_bit = maxpages - 1; error = -EINVAL; + if (!maxpages) + goto bad_swap; + if (swap_header->info.nr_badpages && S_ISREG(inode->i_mode)) + goto bad_swap; if (swap_header->info.nr_badpages > MAX_SWAP_BADPAGES) goto bad_swap; @@ -1470,25 +1475,27 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) if (error) goto bad_swap; } - + if (swapfilesize && maxpages > swapfilesize) { printk(KERN_WARNING "Swap area shorter than signature indicates\n"); error = -EINVAL; goto bad_swap; } + if (nr_good_pages) { + p->swap_map[0] = SWAP_MAP_BAD; + p->max = maxpages; + p->pages = nr_good_pages; + error = setup_swap_extents(p); + if (error) + goto bad_swap; + nr_good_pages = p->pages; + } if (!nr_good_pages) { printk(KERN_WARNING "Empty swap-file\n"); error = -EINVAL; goto bad_swap; } - p->swap_map[0] = SWAP_MAP_BAD; - p->max = maxpages; - p->pages = nr_good_pages; - - error = setup_swap_extents(p); - if (error) - goto bad_swap; down(&swapon_sem); swap_list_lock(); |