Hi Jaegeuk, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk@xxxxxxxxxx] > Sent: Wednesday, August 13, 2014 3:49 AM > To: linux-kernel@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; > linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > Cc: Jaegeuk Kim > Subject: [f2fs-dev] [PATCH 01/13] f2fs: should convert inline_data during the mkwrite > > If mkwrite is called to an inode having inline_data, it can overwrite the data > index space as NEW_ADDR. (e.g., the first 4 bytes are coincidently zero) Good catch! As I did some simple tests, I found that thread will receive SIGBUS when operating mmaped page exceed file size, so here, we will meet a inline data inode only when we mkwrite the first page. Please correct me if I'm wrong. In this case, why not just do f2fs_read_inline_data & skip f2fs_reserve_block, instead of converting inline_data and following f2fs_write_inline_data in ->writepage(). > > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> > --- > fs/f2fs/data.c | 2 +- > fs/f2fs/f2fs.h | 2 +- > fs/f2fs/file.c | 11 ++++++++--- > fs/f2fs/inline.c | 20 ++++++++++++-------- > 4 files changed, 22 insertions(+), 13 deletions(-) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 7aef28d..ac3ccc2 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -946,7 +946,7 @@ static int f2fs_write_begin(struct file *file, struct address_space > *mapping, > > f2fs_balance_fs(sbi); > repeat: > - err = f2fs_convert_inline_data(inode, pos + len); > + err = f2fs_convert_inline_data(inode, pos + len, NULL); > if (err) > goto fail; > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 790a073..c8288c9 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -1439,7 +1439,7 @@ extern const struct inode_operations f2fs_special_inode_operations; > */ > bool f2fs_may_inline(struct inode *); > int f2fs_read_inline_data(struct inode *, struct page *); > -int f2fs_convert_inline_data(struct inode *, pgoff_t); > +int f2fs_convert_inline_data(struct inode *, pgoff_t, struct page *); > int f2fs_write_inline_data(struct inode *, struct page *, unsigned int); > void truncate_inline_data(struct inode *, u64); > int recover_inline_data(struct inode *, struct page *); > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > index 87cdac4..ecbdf6a 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -41,6 +41,11 @@ static int f2fs_vm_page_mkwrite(struct vm_area_struct *vma, > > sb_start_pagefault(inode->i_sb); > > + /* force to convert with normal data indices */ > + err = f2fs_convert_inline_data(inode, MAX_INLINE_DATA + 1, page); > + if (err) > + goto out; > + > /* block allocation */ > f2fs_lock_op(sbi); > set_new_dnode(&dn, inode, NULL, NULL, 0); > @@ -533,7 +538,7 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr) > > if ((attr->ia_valid & ATTR_SIZE) && > attr->ia_size != i_size_read(inode)) { > - err = f2fs_convert_inline_data(inode, attr->ia_size); > + err = f2fs_convert_inline_data(inode, attr->ia_size, NULL); > if (err) > return err; > > @@ -622,7 +627,7 @@ static int punch_hole(struct inode *inode, loff_t offset, loff_t len) > loff_t off_start, off_end; > int ret = 0; > > - ret = f2fs_convert_inline_data(inode, MAX_INLINE_DATA + 1); > + ret = f2fs_convert_inline_data(inode, MAX_INLINE_DATA + 1, NULL); > if (ret) > return ret; > > @@ -678,7 +683,7 @@ static int expand_inode_data(struct inode *inode, loff_t offset, > if (ret) > return ret; > > - ret = f2fs_convert_inline_data(inode, offset + len); > + ret = f2fs_convert_inline_data(inode, offset + len, NULL); > if (ret) > return ret; > > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c > index 5beecce..1ec512d 100644 > --- a/fs/f2fs/inline.c > +++ b/fs/f2fs/inline.c > @@ -124,9 +124,10 @@ out: > return err; > } > > -int f2fs_convert_inline_data(struct inode *inode, pgoff_t to_size) > +int f2fs_convert_inline_data(struct inode *inode, pgoff_t to_size, > + struct page *page) > { > - struct page *page; > + struct page *new_page = page; > int err; > > if (!f2fs_has_inline_data(inode)) > @@ -134,17 +135,20 @@ int f2fs_convert_inline_data(struct inode *inode, pgoff_t to_size) > else if (to_size <= MAX_INLINE_DATA) > return 0; > > - page = grab_cache_page(inode->i_mapping, 0); > - if (!page) > - return -ENOMEM; > + if (!page || page->index != 0) { > + new_page = grab_cache_page(inode->i_mapping, 0); > + if (!new_page) > + return -ENOMEM; > + } > > - err = __f2fs_convert_inline_data(inode, page); > - f2fs_put_page(page, 1); > + err = __f2fs_convert_inline_data(inode, new_page); > + if (!page || page->index != 0) > + f2fs_put_page(new_page, 1); > return err; > } > > int f2fs_write_inline_data(struct inode *inode, > - struct page *page, unsigned size) > + struct page *page, unsigned size) > { > void *src_addr, *dst_addr; > struct page *ipage; > -- > 1.8.5.2 (Apple Git-48) > > > ------------------------------------------------------------------------------ > _______________________________________________ > 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
