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![]() Introduce a new truncate calling sequence into fs/mm subsystems. Rather than setattr > vmtruncate > truncate, have filesystems call their truncate sequence from ->setattr if filesystem specific operations are required. vmtruncate is deprecated, and truncate_pagecache and inode_newsize_ok helpers introduced previously should be used. simple_setattr is introduced for simple in-ram filesystems to implement the new truncate sequence. Eventually all filesystems should be converted to implement a setattr, and the default code in notify_change should go away. simple_setsize is also introduced to perform just the ATTR_SIZE portion of simple_setattr (ie. changing i_size and trimming pagecache). To implement the new truncate sequence: - filesystem specific manipulations (eg freeing blocks) must be done in the setattr method rather than ->truncate. - vmtruncate can not be used by core code to trim blocks past i_size in the event of write failure after allocation, so this must be performed in the fs code. - convert usage of helpers block_write_begin, nobh_write_begin, cont_write_begin, and *blockdev_direct_IO* to use _newtrunc postfixed variants. These avoid calling vmtruncate to trim blocks (see previous). - inode_setattr should not be used. generic_setattr is a new function to be used to copy simple attributes into the generic inode. - make use of the better opportunity to handle errors with the new sequence. Big problem with the previous calling sequence: the filesystem is not called until i_size has already changed. This means it is not allowed to fail the call, and also it does not know what the previous i_size was. Also, generic code calling vmtruncate to truncate allocated blocks in case of error had no good way to return a meaningful error (or, for example, atomically handle block deallocation). Cc: Christoph Hellwig <hch@lst.de> Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> |
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.. | ||
caching | ||
configfs | ||
nfs | ||
pohmelfs | ||
00-INDEX | ||
9p.txt | ||
adfs.txt | ||
affs.txt | ||
afs.txt | ||
autofs4-mount-control.txt | ||
automount-support.txt | ||
befs.txt | ||
bfs.txt | ||
btrfs.txt | ||
ceph.txt | ||
cifs.txt | ||
coda.txt | ||
cramfs.txt | ||
debugfs.txt | ||
dentry-locking.txt | ||
devpts.txt | ||
directory-locking | ||
dlmfs.txt | ||
dnotify.txt | ||
dnotify_test.c | ||
ecryptfs.txt | ||
exofs.txt | ||
ext2.txt | ||
ext3.txt | ||
ext4.txt | ||
fiemap.txt | ||
files.txt | ||
fuse.txt | ||
gfs2-glocks.txt | ||
gfs2-uevents.txt | ||
gfs2.txt | ||
hfs.txt | ||
hfsplus.txt | ||
hpfs.txt | ||
inotify.txt | ||
isofs.txt | ||
jfs.txt | ||
Locking | ||
locks.txt | ||
logfs.txt | ||
Makefile | ||
mandatory-locking.txt | ||
ncpfs.txt | ||
nilfs2.txt | ||
ntfs.txt | ||
ocfs2.txt | ||
omfs.txt | ||
porting | ||
proc.txt | ||
quota.txt | ||
ramfs-rootfs-initramfs.txt | ||
relay.txt | ||
romfs.txt | ||
seq_file.txt | ||
sharedsubtree.txt | ||
smbfs.txt | ||
spufs.txt | ||
squashfs.txt | ||
sysfs-pci.txt | ||
sysfs-tagging.txt | ||
sysfs.txt | ||
sysv-fs.txt | ||
tmpfs.txt | ||
ubifs.txt | ||
udf.txt | ||
ufs.txt | ||
vfat.txt | ||
vfs.txt | ||
xfs-delayed-logging-design.txt | ||
xfs.txt | ||
xip.txt |