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sys_swapon: separate parsing of bad blocks and extents

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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>
This commit is contained in:
Cesar Eduardo Barros 2011-03-22 16:33:32 -07:00 committed by Linus Torvalds
parent 1421ef3cd1
commit 915d4d7bc0
1 changed files with 54 additions and 29 deletions
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83
mm/swapfile.c
View file

@ -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))) {