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authorCesar Eduardo Barros <cesarb@cesarb.net>2011-03-22 16:33:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-22 17:44:08 -0700
commit915d4d7bc0d719f2f0907273c01967d38751c625 (patch)
treedeeab9a10407fa37dedb24d1adc5a83626f740f6 /mm/swapfile.c
parent1421ef3cd15b87ef949e965efeb1e527479d3f75 (diff)
downloadlinux-915d4d7bc0d719f2f0907273c01967d38751c625.tar.bz2
sys_swapon: separate parsing of bad blocks and extents
Move the code which parses the bad block list and the extents to a separate function. Only code movement, no functional changes. This change uses the fact that, after the success path, nr_good_pages == p->pages. Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net> Tested-by: Eric B Munson <emunson@mgebm.net> Acked-by: Eric B Munson <emunson@mgebm.net> Reviewed-by: Pekka Enberg <penberg@kernel.org> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/swapfile.c')
-rw-r--r--mm/swapfile.c83
1 files changed, 54 insertions, 29 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 10f2b33805f6..a0f39f9dc5a5 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1991,6 +1991,54 @@ static unsigned long read_swap_header(struct swap_info_struct *p,
return maxpages;
}
+static int setup_swap_map_and_extents(struct swap_info_struct *p,
+ union swap_header *swap_header,
+ unsigned char *swap_map,
+ unsigned long maxpages,
+ sector_t *span)
+{
+ int i;
+ int error;
+ unsigned int nr_good_pages;
+ int nr_extents;
+
+ nr_good_pages = maxpages - 1; /* omit header page */
+
+ for (i = 0; i < swap_header->info.nr_badpages; i++) {
+ unsigned int page_nr = swap_header->info.badpages[i];
+ if (page_nr == 0 || page_nr > swap_header->info.last_page) {
+ error = -EINVAL;
+ goto bad_swap;
+ }
+ if (page_nr < maxpages) {
+ swap_map[page_nr] = SWAP_MAP_BAD;
+ nr_good_pages--;
+ }
+ }
+
+ if (nr_good_pages) {
+ swap_map[0] = SWAP_MAP_BAD;
+ p->max = maxpages;
+ p->pages = nr_good_pages;
+ nr_extents = setup_swap_extents(p, span);
+ if (nr_extents < 0) {
+ error = nr_extents;
+ goto bad_swap;
+ }
+ nr_good_pages = p->pages;
+ }
+ if (!nr_good_pages) {
+ printk(KERN_WARNING "Empty swap-file\n");
+ error = -EINVAL;
+ goto bad_swap;
+ }
+
+ return nr_extents;
+
+bad_swap:
+ return error;
+}
+
SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
{
struct swap_info_struct *p;
@@ -2001,7 +2049,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
int error;
union swap_header *swap_header;
unsigned int nr_good_pages;
- int nr_extents = 0;
+ int nr_extents;
sector_t span;
unsigned long maxpages;
unsigned char *swap_map = NULL;
@@ -2078,36 +2126,13 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
if (error)
goto bad_swap;
- nr_good_pages = maxpages - 1; /* omit header page */
-
- for (i = 0; i < swap_header->info.nr_badpages; i++) {
- unsigned int page_nr = swap_header->info.badpages[i];
- if (page_nr == 0 || page_nr > swap_header->info.last_page) {
- error = -EINVAL;
- goto bad_swap;
- }
- if (page_nr < maxpages) {
- swap_map[page_nr] = SWAP_MAP_BAD;
- nr_good_pages--;
- }
- }
-
- if (nr_good_pages) {
- swap_map[0] = SWAP_MAP_BAD;
- p->max = maxpages;
- p->pages = nr_good_pages;
- nr_extents = setup_swap_extents(p, &span);
- if (nr_extents < 0) {
- error = nr_extents;
- goto bad_swap;
- }
- nr_good_pages = p->pages;
- }
- if (!nr_good_pages) {
- printk(KERN_WARNING "Empty swap-file\n");
- error = -EINVAL;
+ nr_extents = setup_swap_map_and_extents(p, swap_header, swap_map,
+ maxpages, &span);
+ if (unlikely(nr_extents < 0)) {
+ error = nr_extents;
goto bad_swap;
}
+ nr_good_pages = p->pages;
if (p->bdev) {
if (blk_queue_nonrot(bdev_get_queue(p->bdev))) {