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* NFS: Reduce the stack footprint of nfs_follow_mountpoint()Trond Myklebust2010-05-14
| | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* NFS: Fix nfs_path() to always return a '/' at the beginning of the pathTrond Myklebust2009-06-23
| | | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* switch follow_down()Al Viro2009-06-11
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* nfs: BUG_ON in nfs_follow_mountpointDenis V. Lunev2008-10-07
| | | | | | | | | | | | | | Unfortunately, BUG_ON(IS_ROOT(dentry)) can happen inside nfs_follow_mountpoint with NFS running Fedora 8 using a specific setup. https://bugzilla.redhat.com/show_bug.cgi?id=458622 So, the situation should be handled on NFS client gracefully. Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Trond Myklebust <Trond.Myklebust@netapp.com> CC: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* nfs: ERR_PTR is expected on failure from nfs_do_clone_mountDenis V. Lunev2008-10-07
| | | | | | | Replace NULL with ERR_PTR(-EINVAL). Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* [PATCH] pass struct path * to do_add_mount()Al Viro2008-08-01
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* nfs: path_{get,put}() cleanupsJan Blunck2008-05-16
| | | | | | | | | | | Here are some more places where path_{get,put}() can be used instead of dput()/mntput() pair. Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* nfs: replace remaining __FUNCTION__ occurrencesHarvey Harrison2008-05-16
| | | | | | | | | | __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* make nfs_automount_list staticAdrian Bunk2008-04-19
| | | | | | | nfs_automount_list can now become static. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* Introduce path_put()Jan Blunck2008-02-15
| | | | | | | | | | | | | | | | | | | * Add path_put() functions for releasing a reference to the dentry and vfsmount of a struct path in the right order * Switch from path_release(nd) to path_put(&nd->path) * Rename dput_path() to path_put_conditional() [akpm@linux-foundation.org: fix cifs] Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: <linux-fsdevel@vger.kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Steven French <sfrench@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Embed a struct path into struct nameidata instead of nd->{dentry,mnt}Jan Blunck2008-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the central patch of a cleanup series. In most cases there is no good reason why someone would want to use a dentry for itself. This series reflects that fact and embeds a struct path into nameidata. Together with the other patches of this series - it enforced the correct order of getting/releasing the reference count on <dentry,vfsmount> pairs - it prepares the VFS for stacking support since it is essential to have a struct path in every place where the stack can be traversed - it reduces the overall code size: without patch series: text data bss dec hex filename 5321639 858418 715768 6895825 6938d1 vmlinux with patch series: text data bss dec hex filename 5320026 858418 715768 6894212 693284 vmlinux This patch: Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix cifs] [akpm@linux-foundation.org: fix smack] Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* NFS: Remove the redundant nfs_client->cl_nfsversionTrond Myklebust2008-01-30
| | | | | | We can get the same information from the rpc_ops structure instead. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Fix use of cancel_delayed_work_sync in nfs_release_automount_timerTrond Myklebust2007-09-01
| | | | | | | Doh! We can't use cancel_delayed_work_sync because we may have been called from an unmount that was being performed by nfs_automount_task. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Replace flush_scheduled_work with cancel_work_sync() and friendsTrond Myklebust2007-08-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This will avoid deadlocks of the form: stack backtrace: [<c0104fda>] show_trace_log_lvl+0x1a/0x30 [<c0105c02>] show_trace+0x12/0x20 [<c0105d15>] dump_stack+0x15/0x20 [<c013ee42>] __lock_acquire+0xc22/0x1030 [<c013f2b1>] lock_acquire+0x61/0x80 [<c012edd9>] flush_workqueue+0x49/0x70 [<c012ee0d>] flush_scheduled_work+0xd/0x10 [<dcf55c0c>] nfs_release_automount_timer+0x2c/0x30 [nfs] [<dcf45d8e>] nfs_free_server+0x9e/0xd0 [nfs] [<dcf4e626>] nfs_kill_super+0x16/0x20 [nfs] [<c017b38d>] deactivate_super+0x7d/0xa0 [<c018f94b>] mntput_no_expire+0x4b/0x80 [<c018fd94>] expire_mount_list+0xe4/0x140 [<c0191219>] mark_mounts_for_expiry+0x99/0xb0 [<dcf55d1d>] nfs_expire_automounts+0xd/0x40 [nfs] [<c012e61b>] run_workqueue+0x12b/0x1e0 [<c012f05b>] worker_thread+0x9b/0x100 [<c0131c72>] kthread+0x42/0x70 [<c0104c0f>] kernel_thread_helper+0x7/0x18 ======================= Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* [PATCH] mark struct inode_operations const 2Arjan van de Ven2007-02-12
| | | | | | | | | | | Many struct inode_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* WorkStruct: Pass the work_struct pointer instead of context dataDavid Howells2006-11-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pass the work_struct pointer to the work function rather than context data. The work function can use container_of() to work out the data. For the cases where the container of the work_struct may go away the moment the pending bit is cleared, it is made possible to defer the release of the structure by deferring the clearing of the pending bit. To make this work, an extra flag is introduced into the management side of the work_struct. This governs auto-release of the structure upon execution. Ordinarily, the work queue executor would release the work_struct for further scheduling or deallocation by clearing the pending bit prior to jumping to the work function. This means that, unless the driver makes some guarantee itself that the work_struct won't go away, the work function may not access anything else in the work_struct or its container lest they be deallocated.. This is a problem if the auxiliary data is taken away (as done by the last patch). However, if the pending bit is *not* cleared before jumping to the work function, then the work function *may* access the work_struct and its container with no problems. But then the work function must itself release the work_struct by calling work_release(). In most cases, automatic release is fine, so this is the default. Special initiators exist for the non-auto-release case (ending in _NAR). Signed-Off-By: David Howells <dhowells@redhat.com>
* WorkStruct: Separate delayable and non-delayable events.David Howells2006-11-22
| | | | | | | | | | | | Separate delayable work items from non-delayable work items be splitting them into a separate structure (delayed_work), which incorporates a work_struct and the timer_list removed from work_struct. The work_struct struct is huge, and this limits it's usefulness. On a 64-bit architecture it's nearly 100 bytes in size. This reduces that by half for the non-delayable type of event. Signed-Off-By: David Howells <dhowells@redhat.com>
* Remove all inclusions of <linux/config.h>Dave Jones2006-10-04
| | | | | | kbuild explicitly includes this at build time. Signed-off-by: Dave Jones <davej@redhat.com>
* [PATCH] fs/nfs/: make code staticAdrian Bunk2006-09-27
| | | | | | | Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* NFS: Share NFS superblocks per-protocol per-server per-FSIDDavid Howells2006-09-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Move rpc_ops from nfs_server to nfs_clientDavid Howells2006-09-22
| | | | | | | | Move the rpc_ops from the nfs_server struct to the nfs_client struct as they're common to all server records of a particular NFS protocol version. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Add extra const qualifiersDavid Howells2006-09-22
| | | | | | | Add some extra const qualifiers into NFS. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Release dcache_lock in an error path of nfs_pathJosh Triplett2006-08-03
| | | | | | | | | | In one of the error paths of nfs_path, it may return with dcache_lock still held; fix this by adding and using a new error path Elong_unlock which unlocks dcache_lock. Signed-off-by: Josh Triplett <josh@freedesktop.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> (cherry picked from f4b90b43677fb23297c56802c3056fc304f988d9 commit)
* NFS: Split fs/nfs/inode.cDavid Howells2006-06-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As fs/nfs/inode.c is rather large, heterogenous and unwieldy, the attached patch splits it up into a number of files: (*) fs/nfs/inode.c Strictly inode specific functions. (*) fs/nfs/super.c Superblock management functions for NFS and NFS4, normal access, clones and referrals. The NFS4 superblock functions _could_ move out into a separate conditionally compiled file, but it's probably not worth it as there're so many common bits. (*) fs/nfs/namespace.c Some namespace-specific functions have been moved here. (*) fs/nfs/nfs4namespace.c NFS4-specific namespace functions (this could be merged into the previous file). This file is conditionally compiled. (*) fs/nfs/internal.h Inter-file declarations, plus a few simple utility functions moved from fs/nfs/inode.c. Additionally, all the in-.c-file externs have been moved here, and those files they were moved from now includes this file. For the most part, the functions have not been changed, only some multiplexor functions have changed significantly. I've also: (*) Added some extra banner comments above some functions. (*) Rearranged the function order within the files to be more logical and better grouped (IMO), though someone may prefer a different order. (*) Reduced the number of #ifdefs in .c files. (*) Added missing __init and __exit directives. Signed-Off-By: David Howells <dhowells@redhat.com>
* NFSv4: Follow a referralManoj Naik2006-06-09
| | | | | | | | | | | Respond to a moved error on NFS lookup by setting up the referral. Note: We don't actually follow the referral during lookup/getattr, but later when we detect fsid mismatch in inode revalidation (similar to the processing done for cloning submounts). Referrals will have fake attributes until they are actually followed or traversed. Signed-off-by: Manoj Naik <manoj@almaden.ibm.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Add timeout to submountsTrond Myklebust2006-06-09
| | | | | | | Make automounted partitions expire using the mark_mounts_for_expiry() function. The timeout is controlled via a sysctl. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Ensure the client submounts, when it crosses a server mountpoint.Trond Myklebust2006-06-09
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>