[05/79] libfs: simple_follow_link()
diff mbox

Message ID 1430803373-4948-5-git-send-email-viro@ZenIV.linux.org.uk
State New
Headers show

Commit Message

Al Viro May 5, 2015, 5:21 a.m. UTC
From: Al Viro <viro@zeniv.linux.org.uk>

let "fast" symlinks store the pointer to the body into ->i_link and
use simple_follow_link for ->follow_link()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/inode.c         |  1 +
 fs/libfs.c         | 13 +++++++++++++
 include/linux/fs.h |  3 +++
 3 files changed, 17 insertions(+)

Comments

Jan Kara May 5, 2015, 9:20 a.m. UTC | #1
On Tue 05-05-15 06:21:39, Al Viro wrote:
> From: Al Viro <viro@zeniv.linux.org.uk>
> 
> let "fast" symlinks store the pointer to the body into ->i_link and
> use simple_follow_link for ->follow_link()
> 
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
  Looks good. You can add:
Reviewed-by: Jan Kara <jack@suse.cz>

									Honza

> ---
>  fs/inode.c         |  1 +
>  fs/libfs.c         | 13 +++++++++++++
>  include/linux/fs.h |  3 +++
>  3 files changed, 17 insertions(+)
> 
> diff --git a/fs/inode.c b/fs/inode.c
> index ea37cd1..952fb48 100644
> --- a/fs/inode.c
> +++ b/fs/inode.c
> @@ -152,6 +152,7 @@ int inode_init_always(struct super_block *sb, struct inode *inode)
>  	inode->i_pipe = NULL;
>  	inode->i_bdev = NULL;
>  	inode->i_cdev = NULL;
> +	inode->i_link = NULL;
>  	inode->i_rdev = 0;
>  	inode->dirtied_when = 0;
>  
> diff --git a/fs/libfs.c b/fs/libfs.c
> index cb1fb4b..72e4e01 100644
> --- a/fs/libfs.c
> +++ b/fs/libfs.c
> @@ -1093,3 +1093,16 @@ simple_nosetlease(struct file *filp, long arg, struct file_lock **flp,
>  	return -EINVAL;
>  }
>  EXPORT_SYMBOL(simple_nosetlease);
> +
> +void *simple_follow_link(struct dentry *dentry, struct nameidata *nd)
> +{
> +	nd_set_link(nd, d_inode(dentry)->i_link);
> +	return NULL;
> +}
> +EXPORT_SYMBOL(simple_follow_link);
> +
> +const struct inode_operations simple_symlink_inode_operations = {
> +	.follow_link = simple_follow_link,
> +	.readlink = generic_readlink
> +};
> +EXPORT_SYMBOL(simple_symlink_inode_operations);
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 35ec87e..0ac758f 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -656,6 +656,7 @@ struct inode {
>  		struct pipe_inode_info	*i_pipe;
>  		struct block_device	*i_bdev;
>  		struct cdev		*i_cdev;
> +		char			*i_link;
>  	};
>  
>  	__u32			i_generation;
> @@ -2721,6 +2722,8 @@ void __inode_sub_bytes(struct inode *inode, loff_t bytes);
>  void inode_sub_bytes(struct inode *inode, loff_t bytes);
>  loff_t inode_get_bytes(struct inode *inode);
>  void inode_set_bytes(struct inode *inode, loff_t bytes);
> +void *simple_follow_link(struct dentry *, struct nameidata *);
> +extern const struct inode_operations simple_symlink_inode_operations;
>  
>  extern int iterate_dir(struct file *, struct dir_context *);
>  
> -- 
> 2.1.4
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Patch
diff mbox

diff --git a/fs/inode.c b/fs/inode.c
index ea37cd1..952fb48 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -152,6 +152,7 @@  int inode_init_always(struct super_block *sb, struct inode *inode)
 	inode->i_pipe = NULL;
 	inode->i_bdev = NULL;
 	inode->i_cdev = NULL;
+	inode->i_link = NULL;
 	inode->i_rdev = 0;
 	inode->dirtied_when = 0;
 
diff --git a/fs/libfs.c b/fs/libfs.c
index cb1fb4b..72e4e01 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -1093,3 +1093,16 @@  simple_nosetlease(struct file *filp, long arg, struct file_lock **flp,
 	return -EINVAL;
 }
 EXPORT_SYMBOL(simple_nosetlease);
+
+void *simple_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	nd_set_link(nd, d_inode(dentry)->i_link);
+	return NULL;
+}
+EXPORT_SYMBOL(simple_follow_link);
+
+const struct inode_operations simple_symlink_inode_operations = {
+	.follow_link = simple_follow_link,
+	.readlink = generic_readlink
+};
+EXPORT_SYMBOL(simple_symlink_inode_operations);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 35ec87e..0ac758f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -656,6 +656,7 @@  struct inode {
 		struct pipe_inode_info	*i_pipe;
 		struct block_device	*i_bdev;
 		struct cdev		*i_cdev;
+		char			*i_link;
 	};
 
 	__u32			i_generation;
@@ -2721,6 +2722,8 @@  void __inode_sub_bytes(struct inode *inode, loff_t bytes);
 void inode_sub_bytes(struct inode *inode, loff_t bytes);
 loff_t inode_get_bytes(struct inode *inode);
 void inode_set_bytes(struct inode *inode, loff_t bytes);
+void *simple_follow_link(struct dentry *, struct nameidata *);
+extern const struct inode_operations simple_symlink_inode_operations;
 
 extern int iterate_dir(struct file *, struct dir_context *);