Hi changman, > -----Original Message----- > From: Changman Lee [mailto:cm224.lee@xxxxxxxxxxx] > Sent: Tuesday, May 27, 2014 3:21 PM > To: Chao Yu > Cc: 'Jaegeuk Kim'; linux-fsdevel@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > Subject: Re: [f2fs-dev] [PATCH v2] f2fs: avoid crash when trace f2fs_submit_page_mbio event > in ra_sum_pages > > On Tue, May 27, 2014 at 02:32:57PM +0800, Chao Yu wrote: > > Hi changman, > > > > > -----Original Message----- > > > From: Changman Lee [mailto:cm224.lee@xxxxxxxxxxx] > > > Sent: Tuesday, May 27, 2014 9:25 AM > > > To: Chao Yu > > > Cc: Jaegeuk Kim; linux-fsdevel@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > > > linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > > > Subject: Re: [f2fs-dev] [PATCH v2] f2fs: avoid crash when trace f2fs_submit_page_mbio event > > > in ra_sum_pages > > > > > > Hi, Chao > > > > > > Could you think about following once. > > > move node_inode in front of build_segment_manager, then use node_inode > > > instead of bd_inode. > > > > Jaegeuk and I discussed this solution previously in > > [PATCH 3/3 V3] f2fs: introduce f2fs_cache_node_page() to add page into node_inode cache > > > > You can see it from this url: > > http://sourceforge.net/p/linux-f2fs/mailman/linux-f2fs-devel/?viewmonth=201312&page=5 > > > > And it seems not easy to change order of build_*_manager and make node_inode, > > because there are dependency between them. > > > > Sorry to make a mess your patch thread. It doesn't matter, I think any complaint and suggestion is welcomed here, and thanks for your review. > I've understood it. In your patch, using NAT journal seems to be > possible. Anyway, thanks for your answer. Maybe it could, but now we should discard that patch because previous implementation of ra_sum_pages() which the patch based could cause a crash. Any problem founded here, please tell me, thanks. :) > > > > > > > On Tue, May 27, 2014 at 08:41:07AM +0800, Chao Yu wrote: > > > > Previously we allocate pages with no mapping in ra_sum_pages(), so we may > > > > encounter a crash in event trace of f2fs_submit_page_mbio where we access > > > > mapping data of the page. > > > > > > > > We'd better allocate pages in bd_inode mapping and invalidate these pages after > > > > we restore data from pages. It could avoid crash in above scenario. > > > > > > > > Changes from V1 > > > > o remove redundant code in ra_sum_pages() suggested by Jaegeuk Kim. > > > > > > > > Call Trace: > > > > [<f1031630>] ? ftrace_raw_event_f2fs_write_checkpoint+0x80/0x80 [f2fs] > > > > [<f10377bb>] f2fs_submit_page_mbio+0x1cb/0x200 [f2fs] > > > > [<f103c5da>] restore_node_summary+0x13a/0x280 [f2fs] > > > > [<f103e22d>] build_curseg+0x2bd/0x620 [f2fs] > > > > [<f104043b>] build_segment_manager+0x1cb/0x920 [f2fs] > > > > [<f1032c85>] f2fs_fill_super+0x535/0x8e0 [f2fs] > > > > [<c115b66a>] mount_bdev+0x16a/0x1a0 > > > > [<f102f63f>] f2fs_mount+0x1f/0x30 [f2fs] > > > > [<c115c096>] mount_fs+0x36/0x170 > > > > [<c1173635>] vfs_kern_mount+0x55/0xe0 > > > > [<c1175388>] do_mount+0x1e8/0x900 > > > > [<c1175d72>] SyS_mount+0x82/0xc0 > > > > [<c16059cc>] sysenter_do_call+0x12/0x22 > > > > > > > > Suggested-by: Jaegeuk Kim <jaegeuk.kim@xxxxxxxxxxx> > > > > Signed-off-by: Chao Yu <chao2.yu@xxxxxxxxxxx> > > > > --- > > > > fs/f2fs/node.c | 52 ++++++++++++++++++++++++---------------------------- > > > > 1 file changed, 24 insertions(+), 28 deletions(-) > > > > > > > > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c > > > > index 3d60d3d..02a59e9 100644 > > > > --- a/fs/f2fs/node.c > > > > +++ b/fs/f2fs/node.c > > > > @@ -1658,35 +1658,29 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page) > > > > > > > > /* > > > > * ra_sum_pages() merge contiguous pages into one bio and submit. > > > > - * these pre-readed pages are linked in pages list. > > > > + * these pre-readed pages are alloced in bd_inode's mapping tree. > > > > */ > > > > -static int ra_sum_pages(struct f2fs_sb_info *sbi, struct list_head *pages, > > > > +static int ra_sum_pages(struct f2fs_sb_info *sbi, struct page **pages, > > > > int start, int nrpages) > > > > { > > > > - struct page *page; > > > > - int page_idx = start; > > > > + struct inode *inode = sbi->sb->s_bdev->bd_inode; > > > > + struct address_space *mapping = inode->i_mapping; > > > > + int i, page_idx = start; > > > > struct f2fs_io_info fio = { > > > > .type = META, > > > > .rw = READ_SYNC | REQ_META | REQ_PRIO > > > > }; > > > > > > > > - for (; page_idx < start + nrpages; page_idx++) { > > > > - /* alloc temporal page for read node summary info*/ > > > > - page = alloc_page(GFP_F2FS_ZERO); > > > > - if (!page) > > > > + for (i = 0; page_idx < start + nrpages; page_idx++, i++) { > > > > + /* alloc page in bd_inode for reading node summary info */ > > > > + pages[i] = grab_cache_page(mapping, page_idx); > > > > + if (!pages[i]) > > > > break; > > > > - > > > > - lock_page(page); > > > > - page->index = page_idx; > > > > - list_add_tail(&page->lru, pages); > > > > + f2fs_submit_page_mbio(sbi, pages[i], page_idx, &fio); > > > > } > > > > > > > > - list_for_each_entry(page, pages, lru) > > > > - f2fs_submit_page_mbio(sbi, page, page->index, &fio); > > > > - > > > > f2fs_submit_merged_bio(sbi, META, READ); > > > > - > > > > - return page_idx - start; > > > > + return i; > > > > } > > > > > > > > int restore_node_summary(struct f2fs_sb_info *sbi, > > > > @@ -1694,11 +1688,11 @@ int restore_node_summary(struct f2fs_sb_info *sbi, > > > > { > > > > struct f2fs_node *rn; > > > > struct f2fs_summary *sum_entry; > > > > - struct page *page, *tmp; > > > > + struct inode *inode = sbi->sb->s_bdev->bd_inode; > > > > block_t addr; > > > > int bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi)); > > > > - int i, last_offset, nrpages, err = 0; > > > > - LIST_HEAD(page_list); > > > > + struct page *pages[bio_blocks]; > > > > + int i, idx, last_offset, nrpages, err = 0; > > > > > > > > /* scan the node segment */ > > > > last_offset = sbi->blocks_per_seg; > > > > @@ -1709,29 +1703,31 @@ int restore_node_summary(struct f2fs_sb_info *sbi, > > > > nrpages = min(last_offset - i, bio_blocks); > > > > > > > > /* read ahead node pages */ > > > > - nrpages = ra_sum_pages(sbi, &page_list, addr, nrpages); > > > > + nrpages = ra_sum_pages(sbi, pages, addr, nrpages); > > > > if (!nrpages) > > > > return -ENOMEM; > > > > > > > > - list_for_each_entry_safe(page, tmp, &page_list, lru) { > > > > + for (idx = 0; idx < nrpages; idx++) { > > > > if (err) > > > > goto skip; > > > > > > > > - lock_page(page); > > > > - if (unlikely(!PageUptodate(page))) { > > > > + lock_page(pages[idx]); > > > > + if (unlikely(!PageUptodate(pages[idx]))) { > > > > err = -EIO; > > > > } else { > > > > - rn = F2FS_NODE(page); > > > > + rn = F2FS_NODE(pages[idx]); > > > > sum_entry->nid = rn->footer.nid; > > > > sum_entry->version = 0; > > > > sum_entry->ofs_in_node = 0; > > > > sum_entry++; > > > > } > > > > - unlock_page(page); > > > > + unlock_page(pages[idx]); > > > > skip: > > > > - list_del(&page->lru); > > > > - __free_pages(page, 0); > > > > + page_cache_release(pages[idx]); > > > > } > > > > + > > > > + invalidate_mapping_pages(inode->i_mapping, addr, > > > > + addr + nrpages); > > > > } > > > > return err; > > > > } > > > > -- > > > > 1.7.9.5 > > > > > > > > > > > > > > > > ------------------------------------------------------------------------------ > > > > The best possible search technologies are now affordable for all companies. > > > > Download your FREE open source Enterprise Search Engine today! > > > > Our experts will assist you in its installation for $59/mo, no commitment. > > > > Test it for FREE on our Cloud platform anytime! > > > > http://pubads.g.doubleclick.net/gampad/clk?id=145328191&iu=/4140/ostg.clktrk > > > > _______________________________________________ > > > > Linux-f2fs-devel mailing list > > > > Linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > > > > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
