Commit 81e33971 authored by Hugh Dickins's avatar Hugh Dickins Committed by Linus Torvalds
Browse files

swapfile: remove v0 SWAP-SPACE message 



The kernel has not supported v0 SWAP-SPACE since 2.5.22: I think we can
now safely drop its "version 0 swap is no longer supported" message - just
say "Unable to find swap-space signature" as usual.  This removes one
level of indentation from a stretch of sys_swapon().

I'd have liked to be specific, saying "Unable to find SWAPSPACE2
signature", but it's just too confusing that the version 1 signature shows
the number 2.

Irrelevant nearby cleanup: kmap(page) already gives page_address(page).

Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 886bb7e9

mm/swapfile.c

+65 −81
Original line number Diff line number Diff line
@@ -1456,7 +1456,6 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) 
	int i, prev;

	int error;

	union swap_header *swap_header = NULL;

	int swap_header_version;

	unsigned int nr_good_pages = 0;

	int nr_extents = 0;

	sector_t span;
@@ -1553,26 +1552,14 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) 
		error = PTR_ERR(page);

		goto bad_swap;

	}

	kmap(page);

	swap_header = page_address(page);

	swap_header = kmap(page);



	if (!memcmp("SWAP-SPACE",swap_header->magic.magic,10))

		swap_header_version = 1;

	else if (!memcmp("SWAPSPACE2",swap_header->magic.magic,10))

		swap_header_version = 2;

	else {

	if (memcmp("SWAPSPACE2", swap_header->magic.magic, 10)) {

		printk(KERN_ERR "Unable to find swap-space signature\n");

		error = -EINVAL;

		goto bad_swap;

	}



	switch (swap_header_version) {

	case 1:

		printk(KERN_ERR "version 0 swap is no longer supported. "

			"Use mkswap -v1 %s\n", name);

		error = -EINVAL;

		goto bad_swap;

	case 2:

	/* swap partition endianess hack... */

	if (swab32(swap_header->info.version) == 1) {

		swab32s(&swap_header->info.version);
@@ -1581,8 +1568,7 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) 
		for (i = 0; i < swap_header->info.nr_badpages; i++)

			swab32s(&swap_header->info.badpages[i]);

	}

		/* Check the swap header's sub-version and the size of

                   the swap file and bad block lists */

	/* Check the swap header's sub-version */

	if (swap_header->info.version != 1) {

		printk(KERN_WARNING

		       "Unable to handle swap header version %d\n",
@@ -1608,7 +1594,8 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) 
	 * the swp_entry_t or the architecture definition of a

	 * swap pte.

	 */

		maxpages = swp_offset(pte_to_swp_entry(swp_entry_to_pte(swp_entry(0,~0UL)))) - 1;

	maxpages = swp_offset(pte_to_swp_entry(

			swp_entry_to_pte(swp_entry(0, ~0UL)))) - 1;

	if (maxpages > swap_header->info.last_page)

		maxpages = swap_header->info.last_page;

	p->highest_bit = maxpages - 1;
@@ -1633,21 +1620,18 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags) 
		goto bad_swap;

	}



		error = 0;

	memset(swap_map, 0, maxpages * sizeof(short));

	for (i = 0; i < swap_header->info.nr_badpages; i++) {

		int page_nr = swap_header->info.badpages[i];

			if (page_nr <= 0 || page_nr >= swap_header->info.last_page)

		if (page_nr <= 0 || page_nr >= swap_header->info.last_page) {

			error = -EINVAL;

			else

			goto bad_swap;

		}

		swap_map[page_nr] = SWAP_MAP_BAD;

	}

	nr_good_pages = swap_header->info.last_page -

			swap_header->info.nr_badpages -

			1 /* header page */;

		if (error)

			goto bad_swap;

	}



	if (nr_good_pages) {

		swap_map[0] = SWAP_MAP_BAD;

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