2005-04-17 00:20:36 +02:00
|
|
|
/*
|
|
|
|
* Copyright (c) 2002 Red Hat, Inc. All rights reserved.
|
|
|
|
*
|
|
|
|
* This software may be freely redistributed under the terms of the
|
|
|
|
* GNU General Public License.
|
|
|
|
*
|
|
|
|
* You should have received a copy of the GNU General Public License
|
|
|
|
* along with this program; if not, write to the Free Software
|
|
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
|
|
*
|
2008-06-06 07:46:18 +02:00
|
|
|
* Authors: David Woodhouse <dwmw2@infradead.org>
|
2005-04-17 00:20:36 +02:00
|
|
|
* David Howells <dhowells@redhat.com>
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/kernel.h>
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <linux/init.h>
|
|
|
|
#include <linux/fs.h>
|
|
|
|
#include <linux/pagemap.h>
|
Detach sched.h from mm.h
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.
This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly
Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).
Cross-compile tested on
all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig
as well as my two usual configs.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-20 23:22:52 +02:00
|
|
|
#include <linux/sched.h>
|
2010-08-11 10:38:04 +02:00
|
|
|
#include <linux/mount.h>
|
|
|
|
#include <linux/namei.h>
|
2005-04-17 00:20:36 +02:00
|
|
|
#include "internal.h"
|
|
|
|
|
2017-07-06 16:50:27 +02:00
|
|
|
static const struct inode_operations afs_symlink_inode_operations = {
|
|
|
|
.get_link = page_get_link,
|
|
|
|
.listxattr = afs_listxattr,
|
|
|
|
};
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
/*
|
|
|
|
* map the AFS file status to the inode member variables
|
|
|
|
*/
|
2007-04-27 00:57:07 +02:00
|
|
|
static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct inode *inode = AFS_VNODE_TO_I(vnode);
|
2017-11-02 16:27:49 +01:00
|
|
|
bool changed;
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2007-04-27 00:59:35 +02:00
|
|
|
_debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
|
2005-04-17 00:20:36 +02:00
|
|
|
vnode->status.type,
|
|
|
|
vnode->status.nlink,
|
2007-04-27 01:06:22 +02:00
|
|
|
(unsigned long long) vnode->status.size,
|
2007-04-27 00:55:03 +02:00
|
|
|
vnode->status.data_version,
|
2005-04-17 00:20:36 +02:00
|
|
|
vnode->status.mode);
|
|
|
|
|
2017-11-02 16:27:49 +01:00
|
|
|
read_seqlock_excl(&vnode->cb_lock);
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
switch (vnode->status.type) {
|
|
|
|
case AFS_FTYPE_FILE:
|
|
|
|
inode->i_mode = S_IFREG | vnode->status.mode;
|
|
|
|
inode->i_op = &afs_file_inode_operations;
|
2007-04-27 00:57:07 +02:00
|
|
|
inode->i_fop = &afs_file_operations;
|
2005-04-17 00:20:36 +02:00
|
|
|
break;
|
|
|
|
case AFS_FTYPE_DIR:
|
|
|
|
inode->i_mode = S_IFDIR | vnode->status.mode;
|
|
|
|
inode->i_op = &afs_dir_inode_operations;
|
|
|
|
inode->i_fop = &afs_dir_file_operations;
|
|
|
|
break;
|
|
|
|
case AFS_FTYPE_SYMLINK:
|
2017-03-16 17:27:45 +01:00
|
|
|
/* Symlinks with a mode of 0644 are actually mountpoints. */
|
|
|
|
if ((vnode->status.mode & 0777) == 0644) {
|
|
|
|
inode->i_flags |= S_AUTOMOUNT;
|
|
|
|
|
|
|
|
set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
|
|
|
|
|
|
|
|
inode->i_mode = S_IFDIR | 0555;
|
|
|
|
inode->i_op = &afs_mntpt_inode_operations;
|
|
|
|
inode->i_fop = &afs_mntpt_file_operations;
|
|
|
|
} else {
|
|
|
|
inode->i_mode = S_IFLNK | vnode->status.mode;
|
2017-07-06 16:50:27 +02:00
|
|
|
inode->i_op = &afs_symlink_inode_operations;
|
2017-03-16 17:27:45 +01:00
|
|
|
}
|
2015-11-17 07:07:57 +01:00
|
|
|
inode_nohighmem(inode);
|
2005-04-17 00:20:36 +02:00
|
|
|
break;
|
|
|
|
default:
|
|
|
|
printk("kAFS: AFS vnode with undefined type\n");
|
2017-11-02 16:27:49 +01:00
|
|
|
read_sequnlock_excl(&vnode->cb_lock);
|
2005-04-17 00:20:36 +02:00
|
|
|
return -EBADMSG;
|
|
|
|
}
|
|
|
|
|
2017-11-02 16:27:49 +01:00
|
|
|
changed = (vnode->status.size != inode->i_size);
|
2009-04-03 17:42:41 +02:00
|
|
|
|
2011-10-28 14:13:29 +02:00
|
|
|
set_nlink(inode, vnode->status.nlink);
|
2005-04-17 00:20:36 +02:00
|
|
|
inode->i_uid = vnode->status.owner;
|
2017-03-16 17:27:43 +01:00
|
|
|
inode->i_gid = vnode->status.group;
|
2005-04-17 00:20:36 +02:00
|
|
|
inode->i_size = vnode->status.size;
|
2017-03-16 17:27:47 +01:00
|
|
|
inode->i_ctime.tv_sec = vnode->status.mtime_client;
|
2005-04-17 00:20:36 +02:00
|
|
|
inode->i_ctime.tv_nsec = 0;
|
|
|
|
inode->i_atime = inode->i_mtime = inode->i_ctime;
|
|
|
|
inode->i_blocks = 0;
|
2011-06-14 01:45:44 +02:00
|
|
|
inode->i_generation = vnode->fid.unique;
|
|
|
|
inode->i_version = vnode->status.data_version;
|
2005-04-17 00:20:36 +02:00
|
|
|
inode->i_mapping->a_ops = &afs_fs_aops;
|
2017-11-02 16:27:49 +01:00
|
|
|
|
|
|
|
read_sequnlock_excl(&vnode->cb_lock);
|
|
|
|
|
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
|
|
if (changed)
|
|
|
|
fscache_attr_changed(vnode->cache);
|
|
|
|
#endif
|
2005-04-17 00:20:36 +02:00
|
|
|
return 0;
|
2007-04-27 00:49:28 +02:00
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
/*
|
|
|
|
* iget5() comparator
|
|
|
|
*/
|
2017-11-02 16:27:49 +01:00
|
|
|
int afs_iget5_test(struct inode *inode, void *opaque)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct afs_iget_data *data = opaque;
|
|
|
|
|
|
|
|
return inode->i_ino == data->fid.vnode &&
|
2011-06-14 01:45:44 +02:00
|
|
|
inode->i_generation == data->fid.unique;
|
2007-04-27 00:49:28 +02:00
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2010-08-11 10:38:04 +02:00
|
|
|
/*
|
|
|
|
* iget5() comparator for inode created by autocell operations
|
|
|
|
*
|
|
|
|
* These pseudo inodes don't match anything.
|
|
|
|
*/
|
|
|
|
static int afs_iget5_autocell_test(struct inode *inode, void *opaque)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
/*
|
|
|
|
* iget5() inode initialiser
|
|
|
|
*/
|
|
|
|
static int afs_iget5_set(struct inode *inode, void *opaque)
|
|
|
|
{
|
|
|
|
struct afs_iget_data *data = opaque;
|
|
|
|
struct afs_vnode *vnode = AFS_FS_I(inode);
|
|
|
|
|
|
|
|
inode->i_ino = data->fid.vnode;
|
2011-06-14 01:45:44 +02:00
|
|
|
inode->i_generation = data->fid.unique;
|
2005-04-17 00:20:36 +02:00
|
|
|
vnode->fid = data->fid;
|
|
|
|
vnode->volume = data->volume;
|
|
|
|
|
|
|
|
return 0;
|
2007-04-27 00:49:28 +02:00
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2010-08-11 10:38:04 +02:00
|
|
|
/*
|
|
|
|
* inode retrieval for autocell
|
|
|
|
*/
|
|
|
|
struct inode *afs_iget_autocell(struct inode *dir, const char *dev_name,
|
|
|
|
int namesz, struct key *key)
|
|
|
|
{
|
|
|
|
struct afs_iget_data data;
|
|
|
|
struct afs_super_info *as;
|
|
|
|
struct afs_vnode *vnode;
|
|
|
|
struct super_block *sb;
|
|
|
|
struct inode *inode;
|
|
|
|
static atomic_t afs_autocell_ino;
|
|
|
|
|
|
|
|
_enter("{%x:%u},%*.*s,",
|
|
|
|
AFS_FS_I(dir)->fid.vid, AFS_FS_I(dir)->fid.vnode,
|
|
|
|
namesz, namesz, dev_name ?: "");
|
|
|
|
|
|
|
|
sb = dir->i_sb;
|
|
|
|
as = sb->s_fs_info;
|
|
|
|
data.volume = as->volume;
|
|
|
|
data.fid.vid = as->volume->vid;
|
|
|
|
data.fid.unique = 0;
|
|
|
|
data.fid.vnode = 0;
|
|
|
|
|
|
|
|
inode = iget5_locked(sb, atomic_inc_return(&afs_autocell_ino),
|
|
|
|
afs_iget5_autocell_test, afs_iget5_set,
|
|
|
|
&data);
|
|
|
|
if (!inode) {
|
|
|
|
_leave(" = -ENOMEM");
|
|
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
}
|
|
|
|
|
|
|
|
_debug("GOT INODE %p { ino=%lu, vl=%x, vn=%x, u=%x }",
|
|
|
|
inode, inode->i_ino, data.fid.vid, data.fid.vnode,
|
|
|
|
data.fid.unique);
|
|
|
|
|
|
|
|
vnode = AFS_FS_I(inode);
|
|
|
|
|
|
|
|
/* there shouldn't be an existing inode */
|
|
|
|
BUG_ON(!(inode->i_state & I_NEW));
|
|
|
|
|
|
|
|
inode->i_size = 0;
|
|
|
|
inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
|
|
|
|
inode->i_op = &afs_autocell_inode_operations;
|
2011-10-28 14:13:29 +02:00
|
|
|
set_nlink(inode, 2);
|
2012-02-08 01:20:48 +01:00
|
|
|
inode->i_uid = GLOBAL_ROOT_UID;
|
|
|
|
inode->i_gid = GLOBAL_ROOT_GID;
|
2010-08-11 10:38:04 +02:00
|
|
|
inode->i_ctime.tv_sec = get_seconds();
|
|
|
|
inode->i_ctime.tv_nsec = 0;
|
|
|
|
inode->i_atime = inode->i_mtime = inode->i_ctime;
|
|
|
|
inode->i_blocks = 0;
|
|
|
|
inode->i_version = 0;
|
|
|
|
inode->i_generation = 0;
|
|
|
|
|
|
|
|
set_bit(AFS_VNODE_PSEUDODIR, &vnode->flags);
|
2011-01-14 20:04:05 +01:00
|
|
|
set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
|
|
|
|
inode->i_flags |= S_AUTOMOUNT | S_NOATIME;
|
2010-08-11 10:38:04 +02:00
|
|
|
unlock_new_inode(inode);
|
|
|
|
_leave(" = %p", inode);
|
|
|
|
return inode;
|
|
|
|
}
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
/*
|
|
|
|
* inode retrieval
|
|
|
|
*/
|
2007-04-27 00:59:35 +02:00
|
|
|
struct inode *afs_iget(struct super_block *sb, struct key *key,
|
|
|
|
struct afs_fid *fid, struct afs_file_status *status,
|
|
|
|
struct afs_callback *cb)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct afs_iget_data data = { .fid = *fid };
|
|
|
|
struct afs_super_info *as;
|
|
|
|
struct afs_vnode *vnode;
|
|
|
|
struct inode *inode;
|
|
|
|
int ret;
|
|
|
|
|
2007-05-09 11:33:45 +02:00
|
|
|
_enter(",{%x:%u.%u},,", fid->vid, fid->vnode, fid->unique);
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
as = sb->s_fs_info;
|
|
|
|
data.volume = as->volume;
|
|
|
|
|
|
|
|
inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
|
|
|
|
&data);
|
|
|
|
if (!inode) {
|
|
|
|
_leave(" = -ENOMEM");
|
2007-04-27 00:55:03 +02:00
|
|
|
return ERR_PTR(-ENOMEM);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
2007-04-27 00:55:03 +02:00
|
|
|
_debug("GOT INODE %p { vl=%x vn=%x, u=%x }",
|
|
|
|
inode, fid->vid, fid->vnode, fid->unique);
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
vnode = AFS_FS_I(inode);
|
|
|
|
|
|
|
|
/* deal with an existing inode */
|
|
|
|
if (!(inode->i_state & I_NEW)) {
|
2007-04-27 00:55:03 +02:00
|
|
|
_leave(" = %p", inode);
|
|
|
|
return inode;
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
2007-04-27 00:59:35 +02:00
|
|
|
if (!status) {
|
|
|
|
/* it's a remotely extant inode */
|
afs: Overhaul permit caching
Overhaul permit caching in AFS by making it per-vnode and sharing permit
lists where possible.
When most of the fileserver operations are called, they return a status
structure indicating the (revised) details of the vnode or vnodes involved
in the operation. This includes the access mark derived from the ACL
(named CallerAccess in the protocol definition file). This is cacheable
and if the ACL changes, the server will tell us that it is breaking the
callback promise, at which point we can discard the currently cached
permits.
With this patch, the afs_permits structure has, at the end, an array of
{ key, CallerAccess } elements, sorted by key pointer. This is then cached
in a hash table so that it can be shared between vnodes with the same
access permits.
Permit lists can only be shared if they contain the exact same set of
key->CallerAccess mappings.
Note that that table is global rather than being per-net_ns. If the keys
in a permit list cross net_ns boundaries, there is no problem sharing the
cached permits, since the permits are just integer masks.
Since permit lists pin keys, the permit cache also makes it easier for a
future patch to find all occurrences of a key and remove them by means of
setting the afs_permits::invalidated flag and then clearing the appropriate
key pointer. In such an event, memory barriers will need adding.
Lastly, the permit caching is skipped if the server has sent either a
vnode-specific or an entire-server callback since the start of the
operation.
Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-02 16:27:49 +01:00
|
|
|
ret = afs_vnode_fetch_status(vnode, key, true);
|
2007-04-27 00:59:35 +02:00
|
|
|
if (ret < 0)
|
|
|
|
goto bad_inode;
|
|
|
|
} else {
|
|
|
|
/* it's an inode we just created */
|
|
|
|
memcpy(&vnode->status, status, sizeof(vnode->status));
|
|
|
|
|
|
|
|
if (!cb) {
|
|
|
|
/* it's a symlink we just created (the fileserver
|
|
|
|
* didn't give us a callback) */
|
|
|
|
vnode->cb_version = 0;
|
|
|
|
vnode->cb_type = 0;
|
2017-11-02 16:27:49 +01:00
|
|
|
vnode->cb_expires_at = 0;
|
2007-04-27 00:59:35 +02:00
|
|
|
} else {
|
|
|
|
vnode->cb_version = cb->version;
|
|
|
|
vnode->cb_type = cb->type;
|
2017-11-02 16:27:49 +01:00
|
|
|
vnode->cb_expires_at = cb->expiry;
|
|
|
|
set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
|
2007-04-27 00:59:35 +02:00
|
|
|
}
|
2017-11-02 16:27:49 +01:00
|
|
|
|
|
|
|
vnode->cb_expires_at += ktime_get_real_seconds();
|
2007-04-27 00:59:35 +02:00
|
|
|
}
|
|
|
|
|
2009-04-03 17:42:41 +02:00
|
|
|
/* set up caching before mapping the status, as map-status reads the
|
|
|
|
* first page of symlinks to see if they're really mountpoints */
|
|
|
|
inode->i_size = vnode->status.size;
|
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
|
|
vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
|
|
|
|
&afs_vnode_cache_index_def,
|
FS-Cache: Provide the ability to enable/disable cookies
Provide the ability to enable and disable fscache cookies. A disabled cookie
will reject or ignore further requests to:
Acquire a child cookie
Invalidate and update backing objects
Check the consistency of a backing object
Allocate storage for backing page
Read backing pages
Write to backing pages
but still allows:
Checks/waits on the completion of already in-progress objects
Uncaching of pages
Relinquishment of cookies
Two new operations are provided:
(1) Disable a cookie:
void fscache_disable_cookie(struct fscache_cookie *cookie,
bool invalidate);
If the cookie is not already disabled, this locks the cookie against other
dis/enablement ops, marks the cookie as being disabled, discards or
invalidates any backing objects and waits for cessation of activity on any
associated object.
This is a wrapper around a chunk split out of fscache_relinquish_cookie(),
but it reinitialises the cookie such that it can be reenabled.
All possible failures are handled internally. The caller should consider
calling fscache_uncache_all_inode_pages() afterwards to make sure all page
markings are cleared up.
(2) Enable a cookie:
void fscache_enable_cookie(struct fscache_cookie *cookie,
bool (*can_enable)(void *data),
void *data)
If the cookie is not already enabled, this locks the cookie against other
dis/enablement ops, invokes can_enable() and, if the cookie is not an
index cookie, will begin the procedure of acquiring backing objects.
The optional can_enable() function is passed the data argument and returns
a ruling as to whether or not enablement should actually be permitted to
begin.
All possible failures are handled internally. The cookie will only be
marked as enabled if provisional backing objects are allocated.
A later patch will introduce these to NFS. Cookie enablement during nfs_open()
is then contingent on i_writecount <= 0. can_enable() checks for a race
between open(O_RDONLY) and open(O_WRONLY/O_RDWR). This simplifies NFS's cookie
handling and allows us to get rid of open(O_RDONLY) accidentally introducing
caching to an inode that's open for writing already.
One operation has its API modified:
(3) Acquire a cookie.
struct fscache_cookie *fscache_acquire_cookie(
struct fscache_cookie *parent,
const struct fscache_cookie_def *def,
void *netfs_data,
bool enable);
This now has an additional argument that indicates whether the requested
cookie should be enabled by default. It doesn't need the can_enable()
function because the caller must prevent multiple calls for the same netfs
object and it doesn't need to take the enablement lock because no one else
can get at the cookie before this returns.
Signed-off-by: David Howells <dhowells@redhat.com
2013-09-21 01:09:31 +02:00
|
|
|
vnode, true);
|
2009-04-03 17:42:41 +02:00
|
|
|
#endif
|
|
|
|
|
2007-04-27 00:57:07 +02:00
|
|
|
ret = afs_inode_map_status(vnode, key);
|
2007-04-27 00:55:03 +02:00
|
|
|
if (ret < 0)
|
2005-04-17 00:20:36 +02:00
|
|
|
goto bad_inode;
|
|
|
|
|
|
|
|
/* success */
|
2007-04-27 00:59:35 +02:00
|
|
|
clear_bit(AFS_VNODE_UNSET, &vnode->flags);
|
2007-04-27 00:55:03 +02:00
|
|
|
inode->i_flags |= S_NOATIME;
|
2005-04-17 00:20:36 +02:00
|
|
|
unlock_new_inode(inode);
|
2007-04-27 00:55:03 +02:00
|
|
|
_leave(" = %p [CB { v=%u t=%u }]", inode, vnode->cb_version, vnode->cb_type);
|
|
|
|
return inode;
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
/* failure */
|
2007-04-27 00:49:28 +02:00
|
|
|
bad_inode:
|
2009-04-03 17:42:41 +02:00
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
|
|
fscache_relinquish_cookie(vnode->cache, 0);
|
|
|
|
vnode->cache = NULL;
|
|
|
|
#endif
|
2008-02-07 09:15:28 +01:00
|
|
|
iget_failed(inode);
|
2005-04-17 00:20:36 +02:00
|
|
|
_leave(" = %d [bad]", ret);
|
2007-04-27 00:55:03 +02:00
|
|
|
return ERR_PTR(ret);
|
2007-04-27 00:49:28 +02:00
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2007-05-09 11:33:45 +02:00
|
|
|
/*
|
|
|
|
* mark the data attached to an inode as obsolete due to a write on the server
|
|
|
|
* - might also want to ditch all the outstanding writes and dirty pages
|
|
|
|
*/
|
|
|
|
void afs_zap_data(struct afs_vnode *vnode)
|
|
|
|
{
|
2007-05-11 07:22:20 +02:00
|
|
|
_enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
|
2007-05-09 11:33:45 +02:00
|
|
|
|
|
|
|
/* nuke all the non-dirty pages that aren't locked, mapped or being
|
2007-05-11 07:22:20 +02:00
|
|
|
* written back in a regular file and completely discard the pages in a
|
|
|
|
* directory or symlink */
|
|
|
|
if (S_ISREG(vnode->vfs_inode.i_mode))
|
|
|
|
invalidate_remote_inode(&vnode->vfs_inode);
|
|
|
|
else
|
|
|
|
invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
|
2007-05-09 11:33:45 +02:00
|
|
|
}
|
|
|
|
|
2007-04-27 00:59:35 +02:00
|
|
|
/*
|
|
|
|
* validate a vnode/inode
|
|
|
|
* - there are several things we need to check
|
|
|
|
* - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
|
|
|
|
* symlink)
|
|
|
|
* - parent dir metadata changed (security changes)
|
|
|
|
* - dentry data changed (write, truncate)
|
|
|
|
* - dentry metadata changed (security changes)
|
|
|
|
*/
|
|
|
|
int afs_validate(struct afs_vnode *vnode, struct key *key)
|
|
|
|
{
|
2017-11-02 16:27:49 +01:00
|
|
|
time64_t now = ktime_get_real_seconds();
|
|
|
|
bool valid = false;
|
2007-04-27 00:59:35 +02:00
|
|
|
int ret;
|
|
|
|
|
|
|
|
_enter("{v={%x:%u} fl=%lx},%x",
|
|
|
|
vnode->fid.vid, vnode->fid.vnode, vnode->flags,
|
|
|
|
key_serial(key));
|
|
|
|
|
2017-11-02 16:27:49 +01:00
|
|
|
/* Quickly check the callback state. Ideally, we'd use read_seqbegin
|
|
|
|
* here, but we have no way to pass the net namespace to the RCU
|
|
|
|
* cleanup for the server record.
|
|
|
|
*/
|
|
|
|
read_seqlock_excl(&vnode->cb_lock);
|
|
|
|
|
|
|
|
if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
|
|
|
|
if (vnode->cb_s_break != vnode->cb_interest->server->cb_s_break) {
|
|
|
|
vnode->cb_s_break = vnode->cb_interest->server->cb_s_break;
|
|
|
|
} else if (!test_bit(AFS_VNODE_DIR_MODIFIED, &vnode->flags) &&
|
|
|
|
!test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&
|
|
|
|
vnode->cb_expires_at - 10 > now) {
|
|
|
|
valid = true;
|
2007-04-27 00:59:35 +02:00
|
|
|
}
|
2017-11-02 16:27:49 +01:00
|
|
|
} else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
|
|
|
|
valid = true;
|
2007-04-27 00:59:35 +02:00
|
|
|
}
|
|
|
|
|
2017-11-02 16:27:49 +01:00
|
|
|
read_sequnlock_excl(&vnode->cb_lock);
|
|
|
|
if (valid)
|
2007-04-27 00:59:35 +02:00
|
|
|
goto valid;
|
|
|
|
|
|
|
|
mutex_lock(&vnode->validate_lock);
|
|
|
|
|
|
|
|
/* if the promise has expired, we need to check the server again to get
|
|
|
|
* a new promise - note that if the (parent) directory's metadata was
|
|
|
|
* changed then the security may be different and we may no longer have
|
|
|
|
* access */
|
2017-11-02 16:27:49 +01:00
|
|
|
if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
|
2007-04-27 00:59:35 +02:00
|
|
|
_debug("not promised");
|
afs: Overhaul permit caching
Overhaul permit caching in AFS by making it per-vnode and sharing permit
lists where possible.
When most of the fileserver operations are called, they return a status
structure indicating the (revised) details of the vnode or vnodes involved
in the operation. This includes the access mark derived from the ACL
(named CallerAccess in the protocol definition file). This is cacheable
and if the ACL changes, the server will tell us that it is breaking the
callback promise, at which point we can discard the currently cached
permits.
With this patch, the afs_permits structure has, at the end, an array of
{ key, CallerAccess } elements, sorted by key pointer. This is then cached
in a hash table so that it can be shared between vnodes with the same
access permits.
Permit lists can only be shared if they contain the exact same set of
key->CallerAccess mappings.
Note that that table is global rather than being per-net_ns. If the keys
in a permit list cross net_ns boundaries, there is no problem sharing the
cached permits, since the permits are just integer masks.
Since permit lists pin keys, the permit cache also makes it easier for a
future patch to find all occurrences of a key and remove them by means of
setting the afs_permits::invalidated flag and then clearing the appropriate
key pointer. In such an event, memory barriers will need adding.
Lastly, the permit caching is skipped if the server has sent either a
vnode-specific or an entire-server callback since the start of the
operation.
Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-02 16:27:49 +01:00
|
|
|
ret = afs_vnode_fetch_status(vnode, key, false);
|
2017-11-02 16:27:49 +01:00
|
|
|
if (ret < 0) {
|
|
|
|
if (ret == -ENOENT) {
|
|
|
|
set_bit(AFS_VNODE_DELETED, &vnode->flags);
|
|
|
|
ret = -ESTALE;
|
|
|
|
}
|
2007-04-27 00:59:35 +02:00
|
|
|
goto error_unlock;
|
2017-11-02 16:27:49 +01:00
|
|
|
}
|
2007-04-27 00:59:35 +02:00
|
|
|
_debug("new promise [fl=%lx]", vnode->flags);
|
|
|
|
}
|
|
|
|
|
|
|
|
if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
|
|
|
|
_debug("file already deleted");
|
|
|
|
ret = -ESTALE;
|
|
|
|
goto error_unlock;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* if the vnode's data version number changed then its contents are
|
|
|
|
* different */
|
2007-05-09 11:33:45 +02:00
|
|
|
if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
|
|
|
|
afs_zap_data(vnode);
|
2007-04-27 00:59:35 +02:00
|
|
|
|
2017-11-02 16:27:49 +01:00
|
|
|
clear_bit(AFS_VNODE_DIR_MODIFIED, &vnode->flags);
|
2007-04-27 00:59:35 +02:00
|
|
|
mutex_unlock(&vnode->validate_lock);
|
|
|
|
valid:
|
|
|
|
_leave(" = 0");
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
error_unlock:
|
|
|
|
mutex_unlock(&vnode->validate_lock);
|
|
|
|
_leave(" = %d", ret);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
/*
|
|
|
|
* read the attributes of an inode
|
|
|
|
*/
|
statx: Add a system call to make enhanced file info available
Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.
The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode. This change is propagated to the vfs_getattr*()
function.
Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.
========
OVERVIEW
========
The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.
A number of requests were gathered for features to be included. The
following have been included:
(1) Make the fields a consistent size on all arches and make them large.
(2) Spare space, request flags and information flags are provided for
future expansion.
(3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
__s64).
(4) Creation time: The SMB protocol carries the creation time, which could
be exported by Samba, which will in turn help CIFS make use of
FS-Cache as that can be used for coherency data (stx_btime).
This is also specified in NFSv4 as a recommended attribute and could
be exported by NFSD [Steve French].
(5) Lightweight stat: Ask for just those details of interest, and allow a
netfs (such as NFS) to approximate anything not of interest, possibly
without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
Dilger] (AT_STATX_DONT_SYNC).
(6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
its cached attributes are up to date [Trond Myklebust]
(AT_STATX_FORCE_SYNC).
And the following have been left out for future extension:
(7) Data version number: Could be used by userspace NFS servers [Aneesh
Kumar].
Can also be used to modify fill_post_wcc() in NFSD which retrieves
i_version directly, but has just called vfs_getattr(). It could get
it from the kstat struct if it used vfs_xgetattr() instead.
(There's disagreement on the exact semantics of a single field, since
not all filesystems do this the same way).
(8) BSD stat compatibility: Including more fields from the BSD stat such
as creation time (st_btime) and inode generation number (st_gen)
[Jeremy Allison, Bernd Schubert].
(9) Inode generation number: Useful for FUSE and userspace NFS servers
[Bernd Schubert].
(This was asked for but later deemed unnecessary with the
open-by-handle capability available and caused disagreement as to
whether it's a security hole or not).
(10) Extra coherency data may be useful in making backups [Andreas Dilger].
(No particular data were offered, but things like last backup
timestamp, the data version number and the DOS archive bit would come
into this category).
(11) Allow the filesystem to indicate what it can/cannot provide: A
filesystem can now say it doesn't support a standard stat feature if
that isn't available, so if, for instance, inode numbers or UIDs don't
exist or are fabricated locally...
(This requires a separate system call - I have an fsinfo() call idea
for this).
(12) Store a 16-byte volume ID in the superblock that can be returned in
struct xstat [Steve French].
(Deferred to fsinfo).
(13) Include granularity fields in the time data to indicate the
granularity of each of the times (NFSv4 time_delta) [Steve French].
(Deferred to fsinfo).
(14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags.
Note that the Linux IOC flags are a mess and filesystems such as Ext4
define flags that aren't in linux/fs.h, so translation in the kernel
may be a necessity (or, possibly, we provide the filesystem type too).
(Some attributes are made available in stx_attributes, but the general
feeling was that the IOC flags were to ext[234]-specific and shouldn't
be exposed through statx this way).
(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
Michael Kerrisk].
(Deferred, probably to fsinfo. Finding out if there's an ACL or
seclabal might require extra filesystem operations).
(16) Femtosecond-resolution timestamps [Dave Chinner].
(A __reserved field has been left in the statx_timestamp struct for
this - if there proves to be a need).
(17) A set multiple attributes syscall to go with this.
===============
NEW SYSTEM CALL
===============
The new system call is:
int ret = statx(int dfd,
const char *filename,
unsigned int flags,
unsigned int mask,
struct statx *buffer);
The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat(). There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.
Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):
(1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
respect.
(2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
its attributes with the server - which might require data writeback to
occur to get the timestamps correct.
(3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
network filesystem. The resulting values should be considered
approximate.
mask is a bitmask indicating the fields in struct statx that are of
interest to the caller. The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat(). It should be noted that asking for
more information may entail extra I/O operations.
buffer points to the destination for the data. This must be 256 bytes in
size.
======================
MAIN ATTRIBUTES RECORD
======================
The following structures are defined in which to return the main attribute
set:
struct statx_timestamp {
__s64 tv_sec;
__s32 tv_nsec;
__s32 __reserved;
};
struct statx {
__u32 stx_mask;
__u32 stx_blksize;
__u64 stx_attributes;
__u32 stx_nlink;
__u32 stx_uid;
__u32 stx_gid;
__u16 stx_mode;
__u16 __spare0[1];
__u64 stx_ino;
__u64 stx_size;
__u64 stx_blocks;
__u64 __spare1[1];
struct statx_timestamp stx_atime;
struct statx_timestamp stx_btime;
struct statx_timestamp stx_ctime;
struct statx_timestamp stx_mtime;
__u32 stx_rdev_major;
__u32 stx_rdev_minor;
__u32 stx_dev_major;
__u32 stx_dev_minor;
__u64 __spare2[14];
};
The defined bits in request_mask and stx_mask are:
STATX_TYPE Want/got stx_mode & S_IFMT
STATX_MODE Want/got stx_mode & ~S_IFMT
STATX_NLINK Want/got stx_nlink
STATX_UID Want/got stx_uid
STATX_GID Want/got stx_gid
STATX_ATIME Want/got stx_atime{,_ns}
STATX_MTIME Want/got stx_mtime{,_ns}
STATX_CTIME Want/got stx_ctime{,_ns}
STATX_INO Want/got stx_ino
STATX_SIZE Want/got stx_size
STATX_BLOCKS Want/got stx_blocks
STATX_BASIC_STATS [The stuff in the normal stat struct]
STATX_BTIME Want/got stx_btime{,_ns}
STATX_ALL [All currently available stuff]
stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.
Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution. Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.
The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does. The following
attributes map to FS_*_FL flags and are the same numerical value:
STATX_ATTR_COMPRESSED File is compressed by the fs
STATX_ATTR_IMMUTABLE File is marked immutable
STATX_ATTR_APPEND File is append-only
STATX_ATTR_NODUMP File is not to be dumped
STATX_ATTR_ENCRYPTED File requires key to decrypt in fs
Within the kernel, the supported flags are listed by:
KSTAT_ATTR_FS_IOC_FLAGS
[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]
New flags include:
STATX_ATTR_AUTOMOUNT Object is an automount trigger
These are for the use of GUI tools that might want to mark files specially,
depending on what they are.
Fields in struct statx come in a number of classes:
(0) stx_dev_*, stx_blksize.
These are local system information and are always available.
(1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
stx_size, stx_blocks.
These will be returned whether the caller asks for them or not. The
corresponding bits in stx_mask will be set to indicate whether they
actually have valid values.
If the caller didn't ask for them, then they may be approximated. For
example, NFS won't waste any time updating them from the server,
unless as a byproduct of updating something requested.
If the values don't actually exist for the underlying object (such as
UID or GID on a DOS file), then the bit won't be set in the stx_mask,
even if the caller asked for the value. In such a case, the returned
value will be a fabrication.
Note that there are instances where the type might not be valid, for
instance Windows reparse points.
(2) stx_rdev_*.
This will be set only if stx_mode indicates we're looking at a
blockdev or a chardev, otherwise will be 0.
(3) stx_btime.
Similar to (1), except this will be set to 0 if it doesn't exist.
=======
TESTING
=======
The following test program can be used to test the statx system call:
samples/statx/test-statx.c
Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.
Here's some example output. Firstly, an NFS directory that crosses to
another FSID. Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.
[root@andromeda ~]# /tmp/test-statx -A /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:26 Inode: 1703937 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)
Secondly, the result of automounting on that directory.
[root@andromeda ~]# /tmp/test-statx /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:27 Inode: 2 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-01-31 17:46:22 +01:00
|
|
|
int afs_getattr(const struct path *path, struct kstat *stat,
|
|
|
|
u32 request_mask, unsigned int query_flags)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
statx: Add a system call to make enhanced file info available
Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.
The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode. This change is propagated to the vfs_getattr*()
function.
Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.
========
OVERVIEW
========
The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.
A number of requests were gathered for features to be included. The
following have been included:
(1) Make the fields a consistent size on all arches and make them large.
(2) Spare space, request flags and information flags are provided for
future expansion.
(3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
__s64).
(4) Creation time: The SMB protocol carries the creation time, which could
be exported by Samba, which will in turn help CIFS make use of
FS-Cache as that can be used for coherency data (stx_btime).
This is also specified in NFSv4 as a recommended attribute and could
be exported by NFSD [Steve French].
(5) Lightweight stat: Ask for just those details of interest, and allow a
netfs (such as NFS) to approximate anything not of interest, possibly
without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
Dilger] (AT_STATX_DONT_SYNC).
(6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
its cached attributes are up to date [Trond Myklebust]
(AT_STATX_FORCE_SYNC).
And the following have been left out for future extension:
(7) Data version number: Could be used by userspace NFS servers [Aneesh
Kumar].
Can also be used to modify fill_post_wcc() in NFSD which retrieves
i_version directly, but has just called vfs_getattr(). It could get
it from the kstat struct if it used vfs_xgetattr() instead.
(There's disagreement on the exact semantics of a single field, since
not all filesystems do this the same way).
(8) BSD stat compatibility: Including more fields from the BSD stat such
as creation time (st_btime) and inode generation number (st_gen)
[Jeremy Allison, Bernd Schubert].
(9) Inode generation number: Useful for FUSE and userspace NFS servers
[Bernd Schubert].
(This was asked for but later deemed unnecessary with the
open-by-handle capability available and caused disagreement as to
whether it's a security hole or not).
(10) Extra coherency data may be useful in making backups [Andreas Dilger].
(No particular data were offered, but things like last backup
timestamp, the data version number and the DOS archive bit would come
into this category).
(11) Allow the filesystem to indicate what it can/cannot provide: A
filesystem can now say it doesn't support a standard stat feature if
that isn't available, so if, for instance, inode numbers or UIDs don't
exist or are fabricated locally...
(This requires a separate system call - I have an fsinfo() call idea
for this).
(12) Store a 16-byte volume ID in the superblock that can be returned in
struct xstat [Steve French].
(Deferred to fsinfo).
(13) Include granularity fields in the time data to indicate the
granularity of each of the times (NFSv4 time_delta) [Steve French].
(Deferred to fsinfo).
(14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags.
Note that the Linux IOC flags are a mess and filesystems such as Ext4
define flags that aren't in linux/fs.h, so translation in the kernel
may be a necessity (or, possibly, we provide the filesystem type too).
(Some attributes are made available in stx_attributes, but the general
feeling was that the IOC flags were to ext[234]-specific and shouldn't
be exposed through statx this way).
(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
Michael Kerrisk].
(Deferred, probably to fsinfo. Finding out if there's an ACL or
seclabal might require extra filesystem operations).
(16) Femtosecond-resolution timestamps [Dave Chinner].
(A __reserved field has been left in the statx_timestamp struct for
this - if there proves to be a need).
(17) A set multiple attributes syscall to go with this.
===============
NEW SYSTEM CALL
===============
The new system call is:
int ret = statx(int dfd,
const char *filename,
unsigned int flags,
unsigned int mask,
struct statx *buffer);
The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat(). There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.
Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):
(1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
respect.
(2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
its attributes with the server - which might require data writeback to
occur to get the timestamps correct.
(3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
network filesystem. The resulting values should be considered
approximate.
mask is a bitmask indicating the fields in struct statx that are of
interest to the caller. The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat(). It should be noted that asking for
more information may entail extra I/O operations.
buffer points to the destination for the data. This must be 256 bytes in
size.
======================
MAIN ATTRIBUTES RECORD
======================
The following structures are defined in which to return the main attribute
set:
struct statx_timestamp {
__s64 tv_sec;
__s32 tv_nsec;
__s32 __reserved;
};
struct statx {
__u32 stx_mask;
__u32 stx_blksize;
__u64 stx_attributes;
__u32 stx_nlink;
__u32 stx_uid;
__u32 stx_gid;
__u16 stx_mode;
__u16 __spare0[1];
__u64 stx_ino;
__u64 stx_size;
__u64 stx_blocks;
__u64 __spare1[1];
struct statx_timestamp stx_atime;
struct statx_timestamp stx_btime;
struct statx_timestamp stx_ctime;
struct statx_timestamp stx_mtime;
__u32 stx_rdev_major;
__u32 stx_rdev_minor;
__u32 stx_dev_major;
__u32 stx_dev_minor;
__u64 __spare2[14];
};
The defined bits in request_mask and stx_mask are:
STATX_TYPE Want/got stx_mode & S_IFMT
STATX_MODE Want/got stx_mode & ~S_IFMT
STATX_NLINK Want/got stx_nlink
STATX_UID Want/got stx_uid
STATX_GID Want/got stx_gid
STATX_ATIME Want/got stx_atime{,_ns}
STATX_MTIME Want/got stx_mtime{,_ns}
STATX_CTIME Want/got stx_ctime{,_ns}
STATX_INO Want/got stx_ino
STATX_SIZE Want/got stx_size
STATX_BLOCKS Want/got stx_blocks
STATX_BASIC_STATS [The stuff in the normal stat struct]
STATX_BTIME Want/got stx_btime{,_ns}
STATX_ALL [All currently available stuff]
stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.
Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution. Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.
The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does. The following
attributes map to FS_*_FL flags and are the same numerical value:
STATX_ATTR_COMPRESSED File is compressed by the fs
STATX_ATTR_IMMUTABLE File is marked immutable
STATX_ATTR_APPEND File is append-only
STATX_ATTR_NODUMP File is not to be dumped
STATX_ATTR_ENCRYPTED File requires key to decrypt in fs
Within the kernel, the supported flags are listed by:
KSTAT_ATTR_FS_IOC_FLAGS
[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]
New flags include:
STATX_ATTR_AUTOMOUNT Object is an automount trigger
These are for the use of GUI tools that might want to mark files specially,
depending on what they are.
Fields in struct statx come in a number of classes:
(0) stx_dev_*, stx_blksize.
These are local system information and are always available.
(1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
stx_size, stx_blocks.
These will be returned whether the caller asks for them or not. The
corresponding bits in stx_mask will be set to indicate whether they
actually have valid values.
If the caller didn't ask for them, then they may be approximated. For
example, NFS won't waste any time updating them from the server,
unless as a byproduct of updating something requested.
If the values don't actually exist for the underlying object (such as
UID or GID on a DOS file), then the bit won't be set in the stx_mask,
even if the caller asked for the value. In such a case, the returned
value will be a fabrication.
Note that there are instances where the type might not be valid, for
instance Windows reparse points.
(2) stx_rdev_*.
This will be set only if stx_mode indicates we're looking at a
blockdev or a chardev, otherwise will be 0.
(3) stx_btime.
Similar to (1), except this will be set to 0 if it doesn't exist.
=======
TESTING
=======
The following test program can be used to test the statx system call:
samples/statx/test-statx.c
Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.
Here's some example output. Firstly, an NFS directory that crosses to
another FSID. Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.
[root@andromeda ~]# /tmp/test-statx -A /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:26 Inode: 1703937 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)
Secondly, the result of automounting on that directory.
[root@andromeda ~]# /tmp/test-statx /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:27 Inode: 2 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-01-31 17:46:22 +01:00
|
|
|
struct inode *inode = d_inode(path->dentry);
|
2017-11-02 16:27:49 +01:00
|
|
|
struct afs_vnode *vnode = AFS_FS_I(inode);
|
|
|
|
int seq = 0;
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2011-06-14 01:45:44 +02:00
|
|
|
_enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2017-11-02 16:27:49 +01:00
|
|
|
do {
|
|
|
|
read_seqbegin_or_lock(&vnode->cb_lock, &seq);
|
|
|
|
generic_fillattr(inode, stat);
|
|
|
|
} while (need_seqretry(&vnode->cb_lock, seq));
|
|
|
|
|
|
|
|
done_seqretry(&vnode->cb_lock, seq);
|
2005-04-17 00:20:36 +02:00
|
|
|
return 0;
|
2007-04-27 00:49:28 +02:00
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2010-08-11 10:38:04 +02:00
|
|
|
/*
|
|
|
|
* discard an AFS inode
|
|
|
|
*/
|
|
|
|
int afs_drop_inode(struct inode *inode)
|
|
|
|
{
|
|
|
|
_enter("");
|
|
|
|
|
|
|
|
if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
|
|
|
|
return generic_delete_inode(inode);
|
|
|
|
else
|
|
|
|
return generic_drop_inode(inode);
|
|
|
|
}
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
/*
|
|
|
|
* clear an AFS inode
|
|
|
|
*/
|
2010-06-07 20:34:48 +02:00
|
|
|
void afs_evict_inode(struct inode *inode)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct afs_vnode *vnode;
|
|
|
|
|
|
|
|
vnode = AFS_FS_I(inode);
|
|
|
|
|
2017-11-02 16:27:49 +01:00
|
|
|
_enter("{%x:%u.%d}",
|
2007-04-27 00:59:35 +02:00
|
|
|
vnode->fid.vid,
|
2005-04-17 00:20:36 +02:00
|
|
|
vnode->fid.vnode,
|
2017-11-02 16:27:49 +01:00
|
|
|
vnode->fid.unique);
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2007-04-27 00:55:03 +02:00
|
|
|
_debug("CLEAR INODE %p", inode);
|
|
|
|
|
|
|
|
ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
|
|
|
|
|
2014-04-03 23:47:49 +02:00
|
|
|
truncate_inode_pages_final(&inode->i_data);
|
2012-05-03 14:48:02 +02:00
|
|
|
clear_inode(inode);
|
2010-06-07 20:34:48 +02:00
|
|
|
|
2017-11-02 16:27:49 +01:00
|
|
|
if (vnode->cb_interest) {
|
|
|
|
afs_put_cb_interest(afs_i2net(inode), vnode->cb_interest);
|
|
|
|
vnode->cb_interest = NULL;
|
2007-04-27 00:55:03 +02:00
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
AFS: implement basic file write support
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>
2007-05-09 11:33:46 +02:00
|
|
|
ASSERT(list_empty(&vnode->writebacks));
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2009-04-03 17:42:41 +02:00
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
|
|
fscache_relinquish_cookie(vnode->cache, 0);
|
2005-04-17 00:20:36 +02:00
|
|
|
vnode->cache = NULL;
|
|
|
|
#endif
|
|
|
|
|
afs: Overhaul permit caching
Overhaul permit caching in AFS by making it per-vnode and sharing permit
lists where possible.
When most of the fileserver operations are called, they return a status
structure indicating the (revised) details of the vnode or vnodes involved
in the operation. This includes the access mark derived from the ACL
(named CallerAccess in the protocol definition file). This is cacheable
and if the ACL changes, the server will tell us that it is breaking the
callback promise, at which point we can discard the currently cached
permits.
With this patch, the afs_permits structure has, at the end, an array of
{ key, CallerAccess } elements, sorted by key pointer. This is then cached
in a hash table so that it can be shared between vnodes with the same
access permits.
Permit lists can only be shared if they contain the exact same set of
key->CallerAccess mappings.
Note that that table is global rather than being per-net_ns. If the keys
in a permit list cross net_ns boundaries, there is no problem sharing the
cached permits, since the permits are just integer masks.
Since permit lists pin keys, the permit cache also makes it easier for a
future patch to find all occurrences of a key and remove them by means of
setting the afs_permits::invalidated flag and then clearing the appropriate
key pointer. In such an event, memory barriers will need adding.
Lastly, the permit caching is skipped if the server has sent either a
vnode-specific or an entire-server callback since the start of the
operation.
Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-02 16:27:49 +01:00
|
|
|
afs_put_permits(vnode->permit_cache);
|
2005-04-17 00:20:36 +02:00
|
|
|
_leave("");
|
2007-04-27 00:49:28 +02:00
|
|
|
}
|
AFS: implement basic file write support
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>
2007-05-09 11:33:46 +02:00
|
|
|
|
|
|
|
/*
|
|
|
|
* set the attributes of an inode
|
|
|
|
*/
|
|
|
|
int afs_setattr(struct dentry *dentry, struct iattr *attr)
|
|
|
|
{
|
2015-03-17 23:25:59 +01:00
|
|
|
struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
|
AFS: implement basic file write support
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>
2007-05-09 11:33:46 +02:00
|
|
|
struct key *key;
|
|
|
|
int ret;
|
|
|
|
|
2014-10-22 02:11:25 +02:00
|
|
|
_enter("{%x:%u},{n=%pd},%x",
|
|
|
|
vnode->fid.vid, vnode->fid.vnode, dentry,
|
AFS: implement basic file write support
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>
2007-05-09 11:33:46 +02:00
|
|
|
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;
|
|
|
|
}
|