Commit Graph

9207 Commits

Author SHA1 Message Date
Trond Myklebust
1b83d70703 NFS: Protect inode->i_nlink updates using inode->i_lock
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-15 18:10:50 -04:00
Felix Blyakher
d67d1c7bf9 nfs: set correct fl_len in nlmclnt_test()
fcntl(F_GETLK) on an nfs client incorrectly returns
the values for the conflicting lock. fl_len value is
always 1.
If the conflicting lock is (0, 4095) the F_GETLK
request for (1024, 10) returns (0, 1), which doesn't
even cover the requested range, and is quite confusing.
The fix is trivial, set fl_end from the fl_end value
recieved from the nfs server.

Signed-off-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-15 18:08:59 -04:00
Chuck Lever
f45663ce5f NFS: Allow either strict or sloppy mount option parsing
The kernel's NFS client mount option parser currently doesn't allow
unrecognized or incorrect mount options.  This prevents misspellings or
incorrectly specified mount options from possibly causing silent data
corruption.

However, NFS mount options are not standardized, so different operating
systems can use differently spelled mount options to support similar
features, or can support mount options which no other operating system
supports.

"Sloppy" mount option parsing, which allows the parser to ignore any
option it doesn't recognize, is needed to support automounters that often
use maps that are shared between heterogenous operating systems.

The legacy mount command ignores the validity of the values of mount
options entirely, except for the "sec=" and "proto=" options.  If an
incorrect value is specified, the out-of-range value is passed to the
kernel; if a value is specified that contains non-numeric characters,
it appears as though the legacy mount command sets that option to zero
(probably incorrect behavior in general).

In any case, this sets a precedent which we will partially follow for
the kernel mount option parser:

	+ if "sloppy" is not set, the parser will be strict about both
	  unrecognized options (same as legacy) and invalid option
	  values (stricter than legacy)

	+ if "sloppy" is set, the parser will ignore unrecognized
	  options and invalid option values (same as legacy)

An "invalid" option value in this case means that either the type
(integer, short, or string) or sign (for integer values) of the specified
value is incorrect.

This patch does two things: it changes the NFS client's mount option
parsing loop so that it parses the whole string instead of failing at
the first unrecognized option or invalid option value.  An unrecognized
option or an invalid option value cause the option to be skipped.

Then, the patch adds a "sloppy" mount option that allows the parsing
to succeed anyway if there were any problems during parsing.  When
parsing a set of options is complete, if there are errors and "sloppy"
was specified, return success anyway.  Otherwise, only return success
if there are no errors.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:44 -04:00
Chuck Lever
6738b2512b NFS4: Set security flavor default for NFSv4 mounts like other defaults
Set the default security flavor when we set the other mount option
default values for NFSv4.  This cleans up the NFSv4 mount option parsing
path to look like the NFSv2/v3 one.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:43 -04:00
Chuck Lever
dd07c94750 NFS: Set security flavor default for NFSv2/3 mounts like other defaults
Set the default security flavor when we set the other mount option default
values.  After this change, only the legacy user-space mount path needs to
set the NFS_MOUNT_SECFLAVOUR flag.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:42 -04:00
Chuck Lever
01060c896e NFS: Refactor logic for parsing NFS security flavor mount options
Clean up: Refactor the NFS mount option parsing function to extract the
security flavor parsing logic into a separate function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:41 -04:00
Chuck Lever
0e0cab744b NFS: use documenting macro constants for initializing ac{reg, dir}{min, max}
Clean up.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:40 -04:00
Chuck Lever
ed596a8adb NFS: Move the nfs_set_port() call out of nfs_parse_mount_options()
The remount path does not need to set the port in the server address.
Since it's not really a part of option parsing, move the nfs_set_port()
call to nfs_parse_mount_options()'s callers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:39 -04:00
Trond Myklebust
259875efed NFS: set transport defaults after mount option parsing is finished
Move the UDP/TCP default timeo/retrans settings for text mounts to
nfs_init_timeout_values(), which was were they were always being
initialised (and sanity checked) for binary mounts.
Document the default timeout values using appropriate #defines.

Ensure that we initialise and sanity check the transport protocols that
may have been specified by the user.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:38 -04:00
Chuck Lever
40fef8a649 SUNRPC: Use only rpcbind v2 for AF_INET requests
Some server vendors support the higher versions of rpcbind only for
AF_INET6.  The kernel doesn't need to use v3 or v4 for AF_INET anyway,
so change the kernel's rpcbind client to query AF_INET servers over
rpcbind v2 only.

This has a few interesting benefits:

1. If the rpcbind request is going over TCP, and the server doesn't
   support rpcbind versions 3 or 4, the client reduces by two the number
   of ephemeral ports left in TIME_WAIT for each rpcbind request.  This
   will help during NFS mount storms.

2. The rpcbind interaction with servers that don't support rpcbind
   versions 3 or 4 will use less network traffic.  Also helpful
   during mount storms.

3. We can eliminate the kernel build option that controls whether the
   kernel's rpcbind client uses rpcbind version 3 and 4 for AF_INET
   servers.  Less complicated kernel configuration...

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:37 -04:00
Jeff Layton
5afc597c5f nfs4: fix potential race with rapid nfs_callback_up/down cycle
If the nfsv4 callback thread is rapidly brought up and down, it's
possible that nfs_callback_svc might never get a chance to run. If
this happens, the cleanup at thread exit might never occur, throwing
the refcounting off and nfs_callback_info in an incorrect state.

Move the clean functions into nfs_callback_down. Also change the
nfs_callback_info struct to track the svc_rqst rather than svc_serv
since we need to know that to call svc_exit_thread.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:32 -04:00
Jeff Layton
ee84dfc454 nfs4: remove BKL from nfs_callback_up and nfs_callback_down
The nfs_callback_mutex is sufficient protection.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:31 -04:00
Benny Halevy
77e03677ac nfs: initialize timeout variable in nfs4_proc_setclientid_confirm
gcc (4.3.0) rightfully warns about this:
/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/fs/nfs/nfs4proc.c: In function nfs4_proc_setclientid_confirm:
/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/fs/nfs/nfs4proc.c:2936: warning: timeout may be used uninitialized in this function

nfs4_delay that's passed a pointer to 'timeout' is looking at its value
and sets it up to some value in the range: NFS4_POLL_RETRY_MIN..NFS4_POLL_RETRY_MAX
	if (*timeout <= 0)
		*timeout = NFS4_POLL_RETRY_MIN;
	if (*timeout > NFS4_POLL_RETRY_MAX)
		*timeout = NFS4_POLL_RETRY_MAX;

Therefore it will end up set to some sane, though rather indeterministic, value.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:30 -04:00
Chuck Lever
d8e7748ab8 NFS: handle interface identifiers in incoming IPv6 addresses
Add support in the kernel NFS client's address parser for interface
identifiers.

IPv6 link-local addresses require an additional "interface identifier",
which is a network device name or an integer that indexes the array of
local network interfaces.  They are suffixed to the address with a '%'.
For example:

	fe80::215:c5ff:fe3b:e1b2%2

indicates an interface index of 2.  Or

	fe80::215:c5ff:fe3b:e1b2%eth0

indicates that requests should be routed through the eth0 device.
Without the interface ID, link-local addresses are not usable for NFS.

Both the kernel NFS client mount option parser and the mount.nfs command
can take either form.  The mount.nfs command always passes the address
through getnameinfo(3), which usually re-writes interface indices as
device names.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:29 -04:00
Chuck Lever
ce3b7e1906 NFS: Add string length argument to nfs_parse_server_address
To make nfs_parse_server_address() more generally useful, allow it to
accept input strings that are not terminated with '\0'.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:28 -04:00
Chuck Lever
d1aa082573 NFS: Support raw IPv6 address hostnames during NFS mount operation
Traditionally the mount command has looked for a ":" to separate the
server's hostname from the export path in the mounted on device name,
like this:

	mount server:/export /mounted/on/dir

The server's hostname is "server" and the export path is "/export".

You can also substitute a specific IPv4 network address for the server
hostname, like this:

	mount 192.168.0.55:/export /mounted/on/dir

Raw IPv6 addresses present a problem, however, because they look
something like this:

	fe80::200:5aff:fe00:30b

Note the use of colons.

To get around the presence of colons, copy the Solaris convention used for
mounting IPv6 servers by address: wrap a raw IPv6 address with square
brackets.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:27 -04:00
Chuck Lever
dc04589827 NFS: Use common device name parsing logic for NFSv4 and NFSv2/v3
To support passing a raw IPv6 address as a server hostname, we need to
expand the logic that handles splitting the passed-in device name into
a server hostname and export path

Start by pulling device name parsing out of the mount option validation
functions and into separate helper functions.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:26 -04:00
Trond Myklebust
cd10072562 NFS: Fix a dependency on CONFIG_NFS_V4 in nfs_remount
Fix the 'nfs4_fs_type' undeclared error in nfs_remount when compiling sans
NFSv4...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Jeff Layton <jlayton@redhat.com>
2008-07-09 12:09:25 -04:00
Trond Myklebust
e468bae97d NFS: Allow redirtying of a completed unstable write.
Currently, if an unstable write completes, we cannot redirty the page in
order to reflect a new change in the page data until after we've sent a
COMMIT request.

This patch allows a page rewrite to proceed without the unnecessary COMMIT
step, putting it immediately back onto the dirty page list, undoing the
VM unstable write accounting, and removing the NFS_PAGE_TAG_COMMIT tag from
the NFS radix tree.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:24 -04:00
Trond Myklebust
e7d39069e3 NFS: Clean up nfs_update_request()
Simplify the loop in nfs_update_request by moving into a separate function
the code that attempts to update an existing cached NFS write.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:23 -04:00
Chuck Lever
396cee977f NFS: missing newline in NFS mount debugging message
Clean up.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:22 -04:00
Chuck Lever
d33e4dfeab NFS: Treat "intr" and "nointr" options as deprecated
Clean up:  the "intr" and "nointr" mount options were recently retired.
Document this in the NFS mount option parser.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:21 -04:00
Chuck Lever
ecbb3845dd NFS: Allow any value for the "retry" option
The kernel NFS mount option parser should ignore the retry= mount option
since it is meaningful only in user space.  Today it expects a number
rather than arbitrary text, so it ignores the option if the value is
numeric, but chokes if there are other characters in the value.

Change it to allow any text (except ",") as its value.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:20 -04:00
Trond Myklebust
f41f741838 NFS: Ensure we zap only the access and acl caches when setting new acls
...and ensure that we obey the NFS_INO_INVALID_ACL flag when retrieving the
acls.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:19 -04:00
Trond Myklebust
2e96d28672 NFS: Fix a warning in nfs4_async_handle_error
We're not modifying the nfs_server when we call nfs_inc_server_stats and
friends, so allow the compiler to pass 'const' pointers too.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:18 -04:00
Chuck Lever
34e8f92831 NFS: Move fs/nfs/iostat.h to include/linux
The fs/nfs/iostat.h header has definitions that were designed to be exposed
to user space.  Move these definitions under include/linux so user space can
use the definitions in applications that read /proc/self/mountstats.

Also address a handful of coding style issues called out by checkpatch.pl in
fs/nfs/iostat.h.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:17 -04:00
Trond Myklebust
46cb650c22 NFS: Remove the redundant file_open entry from struct nfs_rpc_ops
All instances are set to nfs_open(), so we should just remove the redundant
indirection. Ditto for the file_release op

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:16 -04:00
Trond Myklebust
659bfcd6dd NFS: Fix the ftruncate() credential problem
ftruncate() access checking is supposed to be performed at open() time,
just like reads and writes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:14 -04:00
Olga Kornievskaia
b6b6152c46 rpc: bring back cl_chatty
The cl_chatty flag alows us to control whether a given rpc client leaves

	"server X not responding, timed out"

messages in the syslog.  Such messages make sense for ordinary nfs
clients (where an unresponsive server means applications on the
mountpoint are probably hanging), but not for the callback client (which
can fail more commonly, with the only result just of disabling some
optimizations).

Previously cl_chatty was removed, do to lack of users; reinstate it, and
use it for the nfsd's callback client.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:10 -04:00
Jeff Layton
48b605f83c NFS: implement option checking when remounting NFS filesystems (resend)
When remounting an NFS or NFS4 filesystem, the new NFS options are not
respected, yet the remount will still return success. This patch adds
a remount_fs sb op for NFS that checks any new nfs mount options against
the existing ones and fails the mount if any have changed.

This is only implemented for string-based mount options since doing
this with binary options isn't really feasible.

This is essentially the same as the original patch I sent out, but
adds a check to see if the addr= option has changed.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:09 -04:00
Adrian Bunk
c2d946e55e fs/nfs/nfsroot.c: remove CVS keyword
This patch removes a CVS keyword that wasn't updated for a long time
from a comment.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:08 -04:00
Chuck Lever
48186c7d57 NFS: Fix trace debugging nits in write.c
Clean up: fix a few dprintk messages that still need to show the RPC task ID
correctly, and be sure we use the preferred %lld or %llu instead of %Ld or
%Lu.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:05 -04:00
Chuck Lever
6da24bc9cf NFS: Use NFSDBG_FILE for all fops
Clean up: some fops use NFSDBG_FILE, some use NFSDBG_VFS.  Let's use
NFSDBG_FILE for all fops, and consistently report file names instead
of inode numbers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:04 -04:00
Chuck Lever
b7eaefaa87 NFS: Add debugging facility for NFS aops
Recent work in fs/nfs/file.c neglected to add appropriate trace debugging
for the NFS client's address space operations.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:03 -04:00
Chuck Lever
cc0dd2d105 NFS: Make nfs_open methods consistent
Clean up: Report the same debugging info and count function calls the
same for files and directories in nfs_opendir() and nfs_file_open().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:02 -04:00
Chuck Lever
b84e06c58f NFS: Make nfs_llseek methods consistent
Clean up: Report the same debugging info in nfs_llseek_dir() and
nfs_llseek_file().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:01 -04:00
Chuck Lever
549177863b NFS: Make nfs_fsync methods consistent
Clean up: Report the same debugging info, count function calls the same,
and use similar function naming in nfs_fsync_dir() and nfs_fsync().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:00 -04:00
Chuck Lever
6fb1bc1030 NFS: Update help text for CONFIG_NFS_FS
Clean up: refresh the help text for Kconfig items related to the NFS
client.  Remove obsolete URLs, and make the language consistent among
the options.

Also move the ROOT_NFS config option next to the options related to the
NFS client.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:52 -04:00
Trond Myklebust
b5418383ef NFS: do_setlk(): don't flush caches when we have a delegation
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:50 -04:00
Trond Myklebust
7e5f614660 NFS: Revert commit 44dd151d
Revert commit 44dd151d "NFS: Don't mark a written page as uptodate until it
is on disk". While it is true that the write may fail, that is always the
case. There is no reason why we should treat data on pages that are not
already marked as PG_uptodate as being special. The only thing we gain is a
noticeable slowdown when re-reading these pages.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:46 -04:00
Trond Myklebust
efc91ed019 NFS: Optimise append writes with holes
If a file is being extended, and we're creating a hole, we might as well
declare the entire page to be up to date.

This patch significantly improves the write performance for sparse files
in the case where lseek(SEEK_END) is used to append several non-contiguous
writes at intervals of < PAGE_SIZE.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:45 -04:00
Trond Myklebust
2116271a34 NFS: Add correct bounds checking to NFSv2 locks
NFSv2 file locking currently fails the Connectathon tests, because the
calls to the VFS locking code do not return an EINVAL error if the
struct file_lock overflows the 32-bit boundaries.

The problem is due to the fact that we occasionally call helpers from
fs/locks.c in order to avoid RPC calls to the server when we know that a
local process holds the lock. These helpers are, of course, always
64-bit enabled, so EINVAL is not returned in cases when it would if
the call had gone to the NLM code.

For consistency, we therefore add support for a bounds-checking helper.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:40 -04:00
Trond Myklebust
f3d47a3a6a NFS: Fix a preemption count leak in nfs_update_request
The commit 2785259631 (nfs: use GFP_NOFS
preloads for radix-tree insertion) appears to have introduced a bug:
We only want to call radix_tree_preload() once after creating a request.
Calling it every time we loop after we created the request, will cause
preemption count leaks.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Nick Piggin <npiggin@suse.de>
2008-07-09 12:08:39 -04:00
Trond Myklebust
0b4aae7aad NFS: Reduce the stack usage in NFSv3 create operations
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:38 -04:00
Trond Myklebust
57dc9a5747 NFS: Reduce the stack usage in NFSv4 create operations
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:37 -04:00
Linus Torvalds
f57e91682d Merge branch 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  SUNRPC: Fix an rpcbind breakage for the case of IPv6 lookups
  SUNRPC: Fix a double-free in rpcbind
  NFS: Fix readdir cache invalidation
2008-07-08 12:40:57 -07:00
Jeff Mahoney
eb35c218d8 reiserfs: discard prealloc in reiserfs_delete_inode
With the removal of struct file from the xattr code,
reiserfs_file_release() isn't used anymore, so the prealloc isn't
discarded.  This causes hangs later down the line.

This patch adds it to reiserfs_delete_inode.  In most cases it will be a
no-op due to it already having been called, but will avoid hangs with
xattrs.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-08 12:39:31 -07:00
Trond Myklebust
2aac05a919 NFS: Fix readdir cache invalidation
invalidate_inode_pages2_range() takes page offset arguments, not byte
ranges.

Another thought is that individual pages might perhaps get evicted by VM
pressure, in which case we might perhaps want to re-read not only the
evicted page, but all subsequent pages too (in case the server returns
more/less data per page so that the alignment of the next entry
changes). We should therefore remove the condition that we only do this on
page->index==0.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-08 15:22:40 -04:00
Andrew Morton
5d7e0d2bd9 Fix pagemap_read() use of struct mm_walk
Fix some issues in pagemap_read noted by Alexey:

- initialize pagemap_walk.mm to "mm" , so the code starts working as
  advertised

- initialize ->private to "&pm" so it wouldn't immediately oops in
  pagemap_pte_hole()

- unstatic struct pagemap_walk, so two threads won't fsckup each other
  (including those started by root, including flipping ->mm when you don't
  have permissions)

- pagemap_read() contains two calls to ptrace_may_attach(), second one
  looks unneeded.

- avoid possible kmalloc(0) and integer wraparound.

Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Personally, I'd just remove the functionality entirely  - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-05 13:13:44 -07:00
Andrew Morton
20cbc97261 Fix clear_refs_write() use of struct mm_walk
Don't use a static entry, so as to prevent races during concurrent use
of this function.

Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-05 13:07:56 -07:00