diff mbox series

[17/20] filemap: consistently use ->f_mapping over ->i_mapping

Message ID 20201118084800.2339180-18-hch@lst.de (mailing list archive)
State Superseded
Headers show
Series [01/20] blk-cgroup: fix a hd_struct leak in blkcg_fill_root_iostats | expand

Commit Message

Christoph Hellwig Nov. 18, 2020, 8:47 a.m. UTC 
Use file->f_mapping in all remaining places that have a struct file
available to properly handle the case where inode->i_mapping !=
file_inode(file)->i_mapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 mm/filemap.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

Comments

Jan Kara Nov. 19, 2020, 2:53 p.m. UTC | #1 
On Wed 18-11-20 09:47:57, Christoph Hellwig wrote:
> Use file->f_mapping in all remaining places that have a struct file
> available to properly handle the case where inode->i_mapping !=
> file_inode(file)->i_mapping.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks good. You can add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  mm/filemap.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/mm/filemap.c b/mm/filemap.c
> index d5e7c2029d16b4..3e3531a757f8db 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -2887,13 +2887,13 @@ EXPORT_SYMBOL(filemap_map_pages);
>  vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf)
>  {
>  	struct page *page = vmf->page;
> -	struct inode *inode = file_inode(vmf->vma->vm_file);
> +	struct inode *inode = vmf->vma->vm_file->f_mapping->host;
>  	vm_fault_t ret = VM_FAULT_LOCKED;
>  
>  	sb_start_pagefault(inode->i_sb);
>  	file_update_time(vmf->vma->vm_file);
>  	lock_page(page);
> -	if (page->mapping != inode->i_mapping) {
> +	if (page->mapping != vmf->vma->vm_file->f_mapping) {
>  		unlock_page(page);
>  		ret = VM_FAULT_NOPAGE;
>  		goto out;
> @@ -3149,10 +3149,9 @@ void dio_warn_stale_pagecache(struct file *filp)
>  {
>  	static DEFINE_RATELIMIT_STATE(_rs, 86400 * HZ, DEFAULT_RATELIMIT_BURST);
>  	char pathname[128];
> -	struct inode *inode = file_inode(filp);
>  	char *path;
>  
> -	errseq_set(&inode->i_mapping->wb_err, -EIO);
> +	errseq_set(&filp->f_mapping->wb_err, -EIO);
>  	if (__ratelimit(&_rs)) {
>  		path = file_path(filp, pathname, sizeof(pathname));
>  		if (IS_ERR(path))
> @@ -3179,7 +3178,7 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
>  
>  	if (iocb->ki_flags & IOCB_NOWAIT) {
>  		/* If there are pages to writeback, return */
> -		if (filemap_range_has_page(inode->i_mapping, pos,
> +		if (filemap_range_has_page(file->f_mapping, pos,
>  					   pos + write_len - 1))
>  			return -EAGAIN;
>  	} else {
> -- 
> 2.29.2
>
Matthew Wilcox Nov. 19, 2020, 3:13 p.m. UTC | #2 
On Wed, Nov 18, 2020 at 09:47:57AM +0100, Christoph Hellwig wrote:
> @@ -2887,13 +2887,13 @@ EXPORT_SYMBOL(filemap_map_pages);
>  vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf)
>  {
>  	struct page *page = vmf->page;
> -	struct inode *inode = file_inode(vmf->vma->vm_file);
> +	struct inode *inode = vmf->vma->vm_file->f_mapping->host;
>  	vm_fault_t ret = VM_FAULT_LOCKED;
>  
>  	sb_start_pagefault(inode->i_sb);
>  	file_update_time(vmf->vma->vm_file);
>  	lock_page(page);
> -	if (page->mapping != inode->i_mapping) {
> +	if (page->mapping != vmf->vma->vm_file->f_mapping) {

Bit messy.  I'd do:

	struct address_space *mapping = vmf->vma->vm_file->f_mapping;

	sb_start_pagefault(mapping->host->i_sb);

	if (page->mapping != mapping)

	sb_end_pagefault(mapping->host->i_sb);
Christoph Hellwig Nov. 20, 2020, 9:17 a.m. UTC | #3 
On Thu, Nov 19, 2020 at 03:13:16PM +0000, Matthew Wilcox wrote:
> On Wed, Nov 18, 2020 at 09:47:57AM +0100, Christoph Hellwig wrote:
> > @@ -2887,13 +2887,13 @@ EXPORT_SYMBOL(filemap_map_pages);
> >  vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf)
> >  {
> >  	struct page *page = vmf->page;
> > -	struct inode *inode = file_inode(vmf->vma->vm_file);
> > +	struct inode *inode = vmf->vma->vm_file->f_mapping->host;
> >  	vm_fault_t ret = VM_FAULT_LOCKED;
> >  
> >  	sb_start_pagefault(inode->i_sb);
> >  	file_update_time(vmf->vma->vm_file);
> >  	lock_page(page);
> > -	if (page->mapping != inode->i_mapping) {
> > +	if (page->mapping != vmf->vma->vm_file->f_mapping) {
> 
> Bit messy.  I'd do:
> 
> 	struct address_space *mapping = vmf->vma->vm_file->f_mapping;
> 
> 	sb_start_pagefault(mapping->host->i_sb);
> 
> 	if (page->mapping != mapping)
> 
> 	sb_end_pagefault(mapping->host->i_sb);

Fine with me.
diff mbox series

Patch

diff --git a/mm/filemap.c b/mm/filemap.c
index d5e7c2029d16b4..3e3531a757f8db 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2887,13 +2887,13 @@  EXPORT_SYMBOL(filemap_map_pages);
 vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf)
 {
 	struct page *page = vmf->page;
-	struct inode *inode = file_inode(vmf->vma->vm_file);
+	struct inode *inode = vmf->vma->vm_file->f_mapping->host;
 	vm_fault_t ret = VM_FAULT_LOCKED;
 
 	sb_start_pagefault(inode->i_sb);
 	file_update_time(vmf->vma->vm_file);
 	lock_page(page);
-	if (page->mapping != inode->i_mapping) {
+	if (page->mapping != vmf->vma->vm_file->f_mapping) {
 		unlock_page(page);
 		ret = VM_FAULT_NOPAGE;
 		goto out;
@@ -3149,10 +3149,9 @@  void dio_warn_stale_pagecache(struct file *filp)
 {
 	static DEFINE_RATELIMIT_STATE(_rs, 86400 * HZ, DEFAULT_RATELIMIT_BURST);
 	char pathname[128];
-	struct inode *inode = file_inode(filp);
 	char *path;
 
-	errseq_set(&inode->i_mapping->wb_err, -EIO);
+	errseq_set(&filp->f_mapping->wb_err, -EIO);
 	if (__ratelimit(&_rs)) {
 		path = file_path(filp, pathname, sizeof(pathname));
 		if (IS_ERR(path))
@@ -3179,7 +3178,7 @@  generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
 
 	if (iocb->ki_flags & IOCB_NOWAIT) {
 		/* If there are pages to writeback, return */
-		if (filemap_range_has_page(inode->i_mapping, pos,
+		if (filemap_range_has_page(file->f_mapping, pos,
 					   pos + write_len - 1))
 			return -EAGAIN;
 	} else {