f2fs: check truncation of mapping after lock_page

We call lock_page when we need to update a page after readpage.
Between grab and lock page, the page can be truncated by other thread.
So, we should check the page after lock_page whether it was truncated or not.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

4 files changed, 39 insertions, 7 deletions

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 590ea50c80a7..b1de01da1a40 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -65,6 +65,10 @@ repeat:
                 goto repeat;
 
         lock_page(page);
+        if (page->mapping != mapping) {
+                f2fs_put_page(page, 1);
+                goto repeat;
+        }
 out:
         mark_page_accessed(page);
         return page;
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index eba7e84d1ffd..2db9380f5dda 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -240,7 +240,7 @@ struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
 
         if (dn.data_blkaddr == NULL_ADDR)
                 return ERR_PTR(-ENOENT);
-
+repeat:
         page = grab_cache_page(mapping, index);
         if (!page)
                 return ERR_PTR(-ENOMEM);
@@ -260,6 +260,10 @@ struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
                 f2fs_put_page(page, 1);
                 return ERR_PTR(-EIO);
         }
+        if (page->mapping != mapping) {
+                f2fs_put_page(page, 1);
+                goto repeat;
+        }
         return page;
 }
 
@@ -291,7 +295,7 @@ struct page *get_new_data_page(struct inode *inode, pgoff_t index,
                 }
         }
         f2fs_put_dnode(&dn);
-
+repeat:
         page = grab_cache_page(mapping, index);
         if (!page)
                 return ERR_PTR(-ENOMEM);
@@ -311,6 +315,10 @@ struct page *get_new_data_page(struct inode *inode, pgoff_t index,
                         f2fs_put_page(page, 1);
                         return ERR_PTR(-EIO);
                 }
+                if (page->mapping != mapping) {
+                        f2fs_put_page(page, 1);
+                        goto repeat;
+                }
         }
 
         if (new_i_size &&
@@ -611,7 +619,7 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping,
         *fsdata = NULL;
 
         f2fs_balance_fs(sbi);
-
+repeat:
         page = grab_cache_page_write_begin(mapping, index, flags);
         if (!page)
                 return -ENOMEM;
@@ -656,6 +664,10 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping,
                         f2fs_put_page(page, 1);
                         return -EIO;
                 }
+                if (page->mapping != mapping) {
+                        f2fs_put_page(page, 1);
+                        goto repeat;
+                }
         }
 out:
         SetPageUptodate(page);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 9dfcdab5ea7c..3e2c2cbc500c 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -217,6 +217,10 @@ static void truncate_partial_data_page(struct inode *inode, u64 from)
                 return;
 
         lock_page(page);
+        if (page->mapping != inode->i_mapping) {
+                f2fs_put_page(page, 1);
+                return;
+        }
         wait_on_page_writeback(page);
         zero_user(page, offset, PAGE_CACHE_SIZE - offset);
         set_page_dirty(page);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index aede91071f71..6ff017245522 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -674,6 +674,7 @@ fail:
 int truncate_inode_blocks(struct inode *inode, pgoff_t from)
 {
         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
+        struct address_space *node_mapping = sbi->node_inode->i_mapping;
         int err = 0, cont = 1;
         int level, offset[4], noffset[4];
         unsigned int nofs = 0;
@@ -684,7 +685,7 @@ int truncate_inode_blocks(struct inode *inode, pgoff_t from)
         trace_f2fs_truncate_inode_blocks_enter(inode, from);
 
         level = get_node_path(from, offset, noffset);
-
+restart:
         page = get_node_page(sbi, inode->i_ino);
         if (IS_ERR(page)) {
                 trace_f2fs_truncate_inode_blocks_exit(inode, PTR_ERR(page));
@@ -748,6 +749,10 @@ skip_partial:
                 if (offset[1] == 0 &&
                                 rn->i.i_nid[offset[0] - NODE_DIR1_BLOCK]) {
                         lock_page(page);
+                        if (page->mapping != node_mapping) {
+                                f2fs_put_page(page, 1);
+                                goto restart;
+                        }
                         wait_on_page_writeback(page);
                         rn->i.i_nid[offset[0] - NODE_DIR1_BLOCK] = 0;
                         set_page_dirty(page);
@@ -916,7 +921,7 @@ struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid)
         struct address_space *mapping = sbi->node_inode->i_mapping;
         struct page *page;
         int err;
-
+repeat:
         page = grab_cache_page(mapping, nid);
         if (!page)
                 return ERR_PTR(-ENOMEM);
@@ -932,6 +937,10 @@ struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid)
                 f2fs_put_page(page, 1);
                 return ERR_PTR(-EIO);
         }
+        if (page->mapping != mapping) {
+                f2fs_put_page(page, 1);
+                goto repeat;
+        }
 got_it:
         BUG_ON(nid != nid_of_node(page));
         mark_page_accessed(page);
@@ -955,7 +964,7 @@ struct page *get_node_page_ra(struct page *parent, int start)
         nid = get_nid(parent, start, false);
         if (!nid)
                 return ERR_PTR(-ENOENT);
-
+repeat:
         page = grab_cache_page(mapping, nid);
         if (!page)
                 return ERR_PTR(-ENOMEM);
@@ -981,7 +990,10 @@ struct page *get_node_page_ra(struct page *parent, int start)
         blk_finish_plug(&plug);
 
         lock_page(page);
-
+        if (page->mapping != mapping) {
+                f2fs_put_page(page, 1);
+                goto repeat;
+        }
 page_hit:
         if (!PageUptodate(page)) {
                 f2fs_put_page(page, 1);