On Thu, Nov 14, 2019 at 03:19:43PM -0800, ira.weiny@xxxxxxxxx wrote: > From: Ira Weiny <ira.weiny@xxxxxxxxx> > > Update the documentation for the move of the swap_* functions out of > address_space_operations and into file_operations. > > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> Looks ok, Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --D > --- > Follow on to the V2 series sent earlier. If I need to spin a V3 I will squash > this into patch 2/2 "fs: Move swap_[de]activate to file_operations" > > 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 >
