kernel.git/fs/nfs/write.c, branch linux-2.6.19.y

[PATCH] NFS: Fix oops in nfs_cancel_commit_list

2006-10-20T17:26:38Z

Fix two bugs: - nfs_inode_remove_request will call nfs_clear_request, so we cannot reference req->wb_page after it. Move the call to dec_zone_page_state so that it occurs while req->wb_page is still valid. - Calling nfs_clear_page_writeback is unnecessary since the radix tree tags will have been cleared by the call to nfs_inode_remove_request. Replace with a simple call to nfs_unlock_request. Signed-off-by: Trond Myklebust Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] separate bdi congestion functions from queue congestion functions

2006-10-20T17:26:35Z

Separate out the concept of "queue congestion" from "backing-dev congestion". Congestion is a backing-dev concept, not a queue concept. The blk_* congestion functions are retained, as wrappers around the core backing-dev congestion functions. This proper layering is needed so that NFS can cleanly use the congestion functions, and so that CONFIG_BLOCK=n actually links. Cc: "Thomas Maier" Cc: "Jens Axboe" Cc: Trond Myklebust Cc: David Howells Cc: Peter Osterlund Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] BLOCK: Remove no-longer necessary linux/mpage.h inclusions [try #6]

2006-09-30T18:52:30Z

Remove inclusions of linux/mpage.h that are no longer necessary due to the transfer of generic_writepages(). Signed-Off-By: David Howells Signed-off-by: Jens Axboe

[PATCH] Really ignore kmem_cache_destroy return value

2006-09-27T15:26:10Z

* Rougly half of callers already do it by not checking return value * Code in drivers/acpi/osl.c does the following to be sure: (void)kmem_cache_destroy(cache); * Those who check it printk something, however, slab_error already printed the name of failed cache. * XFS BUGs on failed kmem_cache_destroy which is not the decision low-level filesystem driver should make. Converted to ignore. Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

NFS: add comments clarifying the use of nfs_post_op_update()

2006-09-23T03:25:05Z

Comments-only change to clarify a detail of the NFS protocol and how it is implemented in Linux. Test plan: None. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust

Add a real API for dealing with blk_congestion_wait()

2006-09-23T03:24:54Z

Signed-off-by: Trond Myklebust

NFS: Share NFS superblocks per-protocol per-server per-FSID

2006-09-23T03:24:37Z

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 Signed-off-by: Trond Myklebust

NFS: Fix nfs_page use after free issues in fs/nfs/write.c

2006-09-19T15:59:10Z

Signed-off-by: Trond Myklebust

[PATCH] NFS: large non-page-aligned direct I/O clobbers memory

2006-09-08T17:22:51Z

The logic in nfs_direct_read_schedule and nfs_direct_write_schedule can allow data->npages to be one larger than rpages. This causes a page pointer to be written beyond the end of the pagevec in nfs_read_data (or nfs_write_data). Fix this by making nfs_(read|write)_alloc() calculate the size of the pagevec array, and initialise data->npages. Also get rid of the redundant argument to nfs_commit_alloc(). Signed-off-by: Trond Myklebust Cc: Chuck Lever Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

NFS: make 2 functions static

2006-08-03T20:55:41Z

nfs_writedata_free() and nfs_readdata_free() can now become static. Signed-off-by: Adrian Bunk Cc: Trond Myklebust Signed-off-by: Andrew Morton Signed-off-by: Trond Myklebust (cherry picked from 5e1ce40f0c3c8f67591aff17756930d7a18ceb1a commit)