lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

AFS: implement basic file write support

Browse Source 
Implement support for writing to regular AFS files, including:

 (1) write

 (2) truncate

 (3) fsync, fdatasync

 (4) chmod, chown, chgrp, utime.

AFS writeback attempts to batch writes into as chunks as large as it can manage
up to the point that it writes back 65535 pages in one chunk or it meets a
locked page.

Furthermore, if a page has been written to using a particular key, then should
another write to that page use some other key, the first write will be flushed
before the second is allowed to take place.  If the first write fails due to a
security error, then the page will be scrapped and reread before the second
write takes place.

If a page is dirty and the callback on it is broken by the server, then the
dirty data is not discarded (same behaviour as NFS).

Shared-writable mappings are not supported by this patch.

[akpm@linux-foundation.org: fix a bunch of warnings]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Howells
2007-05-09 02:33:46 -07:00
committed by Linus Torvalds
parent 416351f28d
commit 31143d5d51
11 changed files with 1483 additions and 27 deletions
Download Patch File Download Diff File Expand all files Collapse all files

47
fs/afs/inode.c
View File

@ -209,7 +209,7 @@ bad_inode:
*/
void afs_zap_data(struct afs_vnode *vnode)
{
kenter("zap data {%x:%u}", vnode->fid.vid, vnode->fid.vnode);
_enter("zap data {%x:%u}", vnode->fid.vid, vnode->fid.vnode);
/* nuke all the non-dirty pages that aren't locked, mapped or being
* written back */
@ -334,6 +334,7 @@ void afs_clear_inode(struct inode *inode)
vnode->server = NULL;
}
ASSERT(list_empty(&vnode->writebacks));
ASSERT(!vnode->cb_promised);
#ifdef AFS_CACHING_SUPPORT
@ -350,3 +351,47 @@ void afs_clear_inode(struct inode *inode)
_leave("");
}
/*
* set the attributes of an inode
*/
int afs_setattr(struct dentry *dentry, struct iattr *attr)
{
struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
struct key *key;
int ret;
_enter("{%x:%u},{n=%s},%x",
vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name,
attr->ia_valid);
if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
ATTR_MTIME))) {
_leave(" = 0 [unsupported]");
return 0;
}
/* flush any dirty data outstanding on a regular file */
if (S_ISREG(vnode->vfs_inode.i_mode)) {
filemap_write_and_wait(vnode->vfs_inode.i_mapping);
afs_writeback_all(vnode);
}
if (attr->ia_valid & ATTR_FILE) {
key = attr->ia_file->private_data;
} else {
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
}
ret = afs_vnode_setattr(vnode, key, attr);
if (!(attr->ia_valid & ATTR_FILE))
key_put(key);
error:
_leave(" = %d", ret);
return ret;
}