redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

add releasepage hooks to block devices which can be used by file systems 

Implement blkdev_releasepage() to release the buffer_heads and pages
after we release private data belonging to a mounted filesystem.

Cc: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
hifive-unleashed-5.1
Theodore Ts'o 2009-01-03 09:47:09 -05:00
parent 0087d9fb3f
commit 87d8fe1ee6
3 changed files with 19 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
fs/block_dev.c
View File

@ -1220,6 +1220,20 @@ static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
return blkdev_ioctl(bdev, mode, cmd, arg);
}
/*
* Try to release a page associated with block device when the system
* is under memory pressure.
*/
static int blkdev_releasepage(struct page *page, gfp_t wait)
{
struct super_block *super = BDEV_I(page->mapping->host)->bdev.bd_super;
if (super && super->s_op->bdev_try_to_free_page)
return super->s_op->bdev_try_to_free_page(super, page, wait);
return try_to_free_buffers(page);
}
static const struct address_space_operations def_blk_aops = {
.readpage = blkdev_readpage,
.writepage = blkdev_writepage,
@ -1227,6 +1241,7 @@ static const struct address_space_operations def_blk_aops = {
.write_begin = blkdev_write_begin,
.write_end = blkdev_write_end,
.writepages = generic_writepages,
.releasepage = blkdev_releasepage,
.direct_IO = blkdev_direct_IO,
};

2
fs/super.c
View File

@ -800,6 +800,7 @@ int get_sb_bdev(struct file_system_type *fs_type,
}
s->s_flags |= MS_ACTIVE;
bdev->bd_super = s;
}
return simple_set_mnt(mnt, s);
@ -819,6 +820,7 @@ void kill_block_super(struct super_block *sb)
struct block_device *bdev = sb->s_bdev;
fmode_t mode = sb->s_mode;
bdev->bd_super = 0;
generic_shutdown_super(sb);
sync_blockdev(bdev);
close_bdev_exclusive(bdev, mode);

2
include/linux/fs.h
View File

@ -565,6 +565,7 @@ struct address_space {
struct block_device {
dev_t bd_dev; /* not a kdev_t - it's a search key */
struct inode * bd_inode; /* will die */
struct super_block * bd_super;
int bd_openers;
struct mutex bd_mutex; /* open/close mutex */
struct semaphore bd_mount_sem;
@ -1385,6 +1386,7 @@ struct super_operations {
ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
#endif
int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
};
/*