diff options
| author | Jan Kara <jack@suse.cz> | 2011-05-24 00:23:34 +0200 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2011-05-26 07:26:44 -0400 |
| commit | 24da4fab5a617ecbf0f0c64e7ba7703383faa411 (patch) | |
| tree | 28f62d2e0e69b11765f021db53c327b56f741576 | |
| parent | 7c6e984dfca8ff5b04d359a59b24f39a691b87d3 (diff) | |
vfs: Create __block_page_mkwrite() helper passing error values back
Create __block_page_mkwrite() helper which does all what block_page_mkwrite()
does except that it passes back errors from __block_write_begin /
block_commit_write calls.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| -rw-r--r-- | fs/buffer.c | 37 | ||||
| -rw-r--r-- | include/linux/buffer_head.h | 14 |
2 files changed, 34 insertions, 17 deletions
diff --git a/fs/buffer.c b/fs/buffer.c index a08bb8e61c6..f6ad8f9b8fa 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2332,23 +2332,22 @@ EXPORT_SYMBOL(block_commit_write); * beyond EOF, then the page is guaranteed safe against truncation until we * unlock the page. */ -int -block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, - get_block_t get_block) +int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, + get_block_t get_block) { struct page *page = vmf->page; struct inode *inode = vma->vm_file->f_path.dentry->d_inode; unsigned long end; loff_t size; - int ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */ + int ret; lock_page(page); size = i_size_read(inode); if ((page->mapping != inode->i_mapping) || (page_offset(page) > size)) { - /* page got truncated out from underneath us */ - unlock_page(page); - goto out; + /* We overload EFAULT to mean page got truncated */ + ret = -EFAULT; + goto out_unlock; } /* page is wholly or partially inside EOF */ @@ -2361,18 +2360,22 @@ block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, if (!ret) ret = block_commit_write(page, 0, end); - if (unlikely(ret)) { - unlock_page(page); - if (ret == -ENOMEM) - ret = VM_FAULT_OOM; - else /* -ENOSPC, -EIO, etc */ - ret = VM_FAULT_SIGBUS; - } else - ret = VM_FAULT_LOCKED; - -out: + if (unlikely(ret < 0)) + goto out_unlock; + return 0; +out_unlock: + unlock_page(page); return ret; } +EXPORT_SYMBOL(__block_page_mkwrite); + +int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, + get_block_t get_block) +{ + int ret = __block_page_mkwrite(vma, vmf, get_block); + + return block_page_mkwrite_return(ret); +} EXPORT_SYMBOL(block_page_mkwrite); /* diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index f5df23561b9..2bf6a9136a9 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -217,8 +217,22 @@ int cont_write_begin(struct file *, struct address_space *, loff_t, get_block_t *, loff_t *); int generic_cont_expand_simple(struct inode *inode, loff_t size); int block_commit_write(struct page *page, unsigned from, unsigned to); +int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, + get_block_t get_block); int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, get_block_t get_block); +/* Convert errno to return value from ->page_mkwrite() call */ +static inline int block_page_mkwrite_return(int err) +{ + if (err == 0) + return VM_FAULT_LOCKED; + if (err == -EFAULT) + return VM_FAULT_NOPAGE; + if (err == -ENOMEM) + return VM_FAULT_OOM; + /* -ENOSPC, -EDQUOT, -EIO ... */ + return VM_FAULT_SIGBUS; +} sector_t generic_block_bmap(struct address_space *, sector_t, get_block_t *); int block_truncate_page(struct address_space *, loff_t, get_block_t *); int nobh_write_begin(struct address_space *, loff_t, unsigned, unsigned, |