[PATCH V3 3/3] Documentation/fs: Move swap_[de]activate() to file_operations

ira.weiny
2019-11-29T16:33:17Z

Update the documentation for the move of the swap_* functions out of
address_space_operations and into file_operations.

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>

---
Changes from V0:
Add to original series (now V3)
Add reviews

Documentation/filesystems/vfs.rst | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst
index 7d4d09dd5e6d..03a740d7faa4 100644
--- a/Documentation/filesystems/vfs.rst
+++ b/Documentation/filesystems/vfs.rst
@@ -731,8 +731,6 @@ cache in your filesystem. The following members are defined:
unsigned long);
void (*is_dirty_writeback) (struct page *, bool *, bool *);
int (*error_remove_page) (struct mapping *mapping, struct page *page);
- int (*swap_activate)(struct file *);
- int (*swap_deactivate)(struct file *);
};

``writepage``
@@ -924,16 +922,6 @@ cache in your filesystem. The following members are defined:
Setting this implies you deal with pages going away under you,
unless you have them locked or reference counts increased.

-``swap_activate``
- Called when swapon is used on a file to allocate space if
- necessary and pin the block lookup information in memory. A
- return value of zero indicates success, in which case this file
- can be used to back swapspace.
-
-``swap_deactivate``
- Called during swapoff on files where swap_activate was
- successful.
-

The File Object
===============
@@ -988,6 +976,8 @@ This describes how the VFS can manipulate an open file. As of kernel
struct file *file_out, loff_t pos_out,
loff_t len, unsigned int remap_flags);
int (*fadvise)(struct file *, loff_t, loff_t, int);
+ int (*swap_activate)(struct file *);
+ int (*swap_deactivate)(struct file *);
};

Again, all methods are called without any locks being held, unless
@@ -1108,6 +1098,16 @@ otherwise noted.
``fadvise``
possibly called by the fadvise64() system call.

+``swap_activate``
+ Called when swapon is used on a file to allocate space if
+ necessary and pin the block lookup information in memory. A
+ return value of zero indicates success, in which case this file
+ can be used to back swapspace.
+
+``swap_deactivate``
+ Called during swapoff on files where swap_activate was
+ successful.
+
Note that the file operations are implemented by the specific
filesystem in which the inode resides. When opening a device node
(character or block special) most filesystems will call special
--
2.21.0