| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <ce4d1663-4082-625f-4c3f-858bf03bbb26@kernel.org>
Date: Fri, 4 Jun 2021 19:12:27 +0800
From: Chao Yu <chao@...nel.org>
To: Chao Yu <yuchao0@...wei.com>, Jaegeuk Kim <jaegeuk@...nel.org>
Cc: linux-f2fs-devel@...ts.sourceforge.net,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] f2fs: swap: remove dead codes
On 2021/5/27 10:12, Chao Yu wrote:
> On 2021/5/27 9:40, Jaegeuk Kim wrote:
>> On 05/26, Chao Yu wrote:
>>> On 2021/5/26 21:30, Jaegeuk Kim wrote:
>>>> On 05/26, Chao Yu wrote:
>>>>> After commit af4b6b8edf6a ("f2fs: introduce check_swap_activate_fast()"),
>>>>> we will never run into original logic of check_swap_activate() before
>>>>> f2fs supports non 4k-sized page, so let's delete those dead codes.
>>>>
>>>> Why not keeping this for large page support in future maybe?
>>>
>>> Well, if so, at that time, it would be better to refactor
>>> check_swap_activate_fast() implementation based on f2fs_map_block() rather
>>> than refactoring check_swap_activate() implementation based on low efficient
>>> bmap()?
>>
>> Let's first check whether we support large page. Have you quickly tested it?
>> If we support it now and current flow is just inefficient, I'd say keeping but
>> refactoring it later.
>
> Let me check this, but I guess it missed to handle large page in lots of flows,
> not sure where we may panic at... :(
I've checked f2fs behavior on 64kb page size in arm64 vm,
- 'ls -ls' will cause f2fs printing "invalid namelen(0), ino:%u, run fsck
to fix." each time.
- after touch a file and umount, fsck reports that image is corrupted.
F2FS uses PAGE_SIZE and F2FS_BLKSIZE directly in a lot of places, I doubt
most of places may not consider large page size condition.
So, thoughts? I guess we have to admit we do not support 64KB page right
now... :P
Thanks,
>
> Thanks,
>
>>
>>>
>>> Thanks,
>>>
>>>>
>>>>>
>>>>> Signed-off-by: Chao Yu <yuchao0@...wei.com>
>>>>> ---
>>>>> fs/f2fs/data.c | 171 +------------------------------------------------
>>>>> 1 file changed, 3 insertions(+), 168 deletions(-)
>>>>>
>>>>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
>>>>> index 3058c7e28b11..9c23fde93b76 100644
>>>>> --- a/fs/f2fs/data.c
>>>>> +++ b/fs/f2fs/data.c
>>>>> @@ -3830,67 +3830,7 @@ int f2fs_migrate_page(struct address_space *mapping,
>>>>> #endif
>>>>> #ifdef CONFIG_SWAP
>>>>> -static int f2fs_is_file_aligned(struct inode *inode)
>>>>> -{
>>>>> - struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
>>>>> - block_t main_blkaddr = SM_I(sbi)->main_blkaddr;
>>>>> - block_t cur_lblock;
>>>>> - block_t last_lblock;
>>>>> - block_t pblock;
>>>>> - unsigned long nr_pblocks;
>>>>> - unsigned int blocks_per_sec = BLKS_PER_SEC(sbi);
>>>>> - unsigned int not_aligned = 0;
>>>>> - int ret = 0;
>>>>> -
>>>>> - cur_lblock = 0;
>>>>> - last_lblock = bytes_to_blks(inode, i_size_read(inode));
>>>>> -
>>>>> - while (cur_lblock < last_lblock) {
>>>>> - struct f2fs_map_blocks map;
>>>>> -
>>>>> - memset(&map, 0, sizeof(map));
>>>>> - map.m_lblk = cur_lblock;
>>>>> - map.m_len = last_lblock - cur_lblock;
>>>>> - map.m_next_pgofs = NULL;
>>>>> - map.m_next_extent = NULL;
>>>>> - map.m_seg_type = NO_CHECK_TYPE;
>>>>> - map.m_may_create = false;
>>>>> -
>>>>> - ret = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_FIEMAP);
>>>>> - if (ret)
>>>>> - goto out;
>>>>> -
>>>>> - /* hole */
>>>>> - if (!(map.m_flags & F2FS_MAP_FLAGS)) {
>>>>> - f2fs_err(sbi, "Swapfile has holes\n");
>>>>> - ret = -ENOENT;
>>>>> - goto out;
>>>>> - }
>>>>> -
>>>>> - pblock = map.m_pblk;
>>>>> - nr_pblocks = map.m_len;
>>>>> -
>>>>> - if ((pblock - main_blkaddr) & (blocks_per_sec - 1) ||
>>>>> - nr_pblocks & (blocks_per_sec - 1)) {
>>>>> - if (f2fs_is_pinned_file(inode)) {
>>>>> - f2fs_err(sbi, "Swapfile does not align to section");
>>>>> - ret = -EINVAL;
>>>>> - goto out;
>>>>> - }
>>>>> - not_aligned++;
>>>>> - }
>>>>> -
>>>>> - cur_lblock += nr_pblocks;
>>>>> - }
>>>>> - if (not_aligned)
>>>>> - f2fs_warn(sbi, "Swapfile (%u) is not align to section: \n"
>>>>> - "\t1) creat(), 2) ioctl(F2FS_IOC_SET_PIN_FILE), 3) fallocate()",
>>>>> - not_aligned);
>>>>> -out:
>>>>> - return ret;
>>>>> -}
>>>>> -
>>>>> -static int check_swap_activate_fast(struct swap_info_struct *sis,
>>>>> +static int check_swap_activate(struct swap_info_struct *sis,
>>>>> struct file *swap_file, sector_t *span)
>>>>> {
>>>>> struct address_space *mapping = swap_file->f_mapping;
>>>>> @@ -3907,6 +3847,8 @@ static int check_swap_activate_fast(struct swap_info_struct *sis,
>>>>> unsigned int not_aligned = 0;
>>>>> int ret = 0;
>>>>> + f2fs_bug_on(sbi, PAGE_SIZE != F2FS_BLKSIZE);
>>>>> +
>>>>> /*
>>>>> * Map all the blocks into the extent list. This code doesn't try
>>>>> * to be very smart.
>>>>> @@ -3986,113 +3928,6 @@ static int check_swap_activate_fast(struct swap_info_struct *sis,
>>>>> return ret;
>>>>> }
>>>>> -/* Copied from generic_swapfile_activate() to check any holes */
>>>>> -static int check_swap_activate(struct swap_info_struct *sis,
>>>>> - struct file *swap_file, sector_t *span)
>>>>> -{
>>>>> - struct address_space *mapping = swap_file->f_mapping;
>>>>> - struct inode *inode = mapping->host;
>>>>> - struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
>>>>> - unsigned blocks_per_page;
>>>>> - unsigned long page_no;
>>>>> - sector_t probe_block;
>>>>> - sector_t last_block;
>>>>> - sector_t lowest_block = -1;
>>>>> - sector_t highest_block = 0;
>>>>> - int nr_extents = 0;
>>>>> - int ret = 0;
>>>>> -
>>>>> - if (PAGE_SIZE == F2FS_BLKSIZE)
>>>>> - return check_swap_activate_fast(sis, swap_file, span);
>>>>> -
>>>>> - ret = f2fs_is_file_aligned(inode);
>>>>> - if (ret)
>>>>> - goto out;
>>>>> -
>>>>> - blocks_per_page = bytes_to_blks(inode, PAGE_SIZE);
>>>>> -
>>>>> - /*
>>>>> - * Map all the blocks into the extent list. This code doesn't try
>>>>> - * to be very smart.
>>>>> - */
>>>>> - probe_block = 0;
>>>>> - page_no = 0;
>>>>> - last_block = bytes_to_blks(inode, i_size_read(inode));
>>>>> - while ((probe_block + blocks_per_page) <= last_block &&
>>>>> - page_no < sis->max) {
>>>>> - unsigned block_in_page;
>>>>> - sector_t first_block;
>>>>> - sector_t block = 0;
>>>>> -
>>>>> - cond_resched();
>>>>> -
>>>>> - block = probe_block;
>>>>> - ret = bmap(inode, &block);
>>>>> - if (ret)
>>>>> - goto out;
>>>>> - if (!block)
>>>>> - goto bad_bmap;
>>>>> - first_block = block;
>>>>> -
>>>>> - /*
>>>>> - * It must be PAGE_SIZE aligned on-disk
>>>>> - */
>>>>> - if (first_block & (blocks_per_page - 1)) {
>>>>> - probe_block++;
>>>>> - goto reprobe;
>>>>> - }
>>>>> -
>>>>> - for (block_in_page = 1; block_in_page < blocks_per_page;
>>>>> - block_in_page++) {
>>>>> -
>>>>> - block = probe_block + block_in_page;
>>>>> - ret = bmap(inode, &block);
>>>>> - if (ret)
>>>>> - goto out;
>>>>> - if (!block)
>>>>> - goto bad_bmap;
>>>>> -
>>>>> - if (block != first_block + block_in_page) {
>>>>> - /* Discontiguity */
>>>>> - probe_block++;
>>>>> - goto reprobe;
>>>>> - }
>>>>> - }
>>>>> -
>>>>> - first_block >>= (PAGE_SHIFT - inode->i_blkbits);
>>>>> - if (page_no) { /* exclude the header page */
>>>>> - if (first_block < lowest_block)
>>>>> - lowest_block = first_block;
>>>>> - if (first_block > highest_block)
>>>>> - highest_block = first_block;
>>>>> - }
>>>>> -
>>>>> - /*
>>>>> - * We found a PAGE_SIZE-length, PAGE_SIZE-aligned run of blocks
>>>>> - */
>>>>> - ret = add_swap_extent(sis, page_no, 1, first_block);
>>>>> - if (ret < 0)
>>>>> - goto out;
>>>>> - nr_extents += ret;
>>>>> - page_no++;
>>>>> - probe_block += blocks_per_page;
>>>>> -reprobe:
>>>>> - continue;
>>>>> - }
>>>>> - ret = nr_extents;
>>>>> - *span = 1 + highest_block - lowest_block;
>>>>> - if (page_no == 0)
>>>>> - page_no = 1; /* force Empty message */
>>>>> - sis->max = page_no;
>>>>> - sis->pages = page_no - 1;
>>>>> - sis->highest_bit = page_no - 1;
>>>>> -out:
>>>>> - return ret;
>>>>> -bad_bmap:
>>>>> - f2fs_err(sbi, "Swapfile has holes\n");
>>>>> - return -EINVAL;
>>>>> -}
>>>>> -
>>>>> static int f2fs_swap_activate(struct swap_info_struct *sis, struct file *file,
>>>>> sector_t *span)
>>>>> {
>>>>> --
>>>>> 2.29.2
>> .
>>
Powered by blists - more mailing lists