diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-06 03:09:16 +0900 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-06 03:09:16 +0900 |
commit | 11126c611e10abb18b6f1ed0300c0548c3906b54 (patch) | |
tree | 246227ad730c1e68f5a9c03db57cd4592abe7687 /fs/fat/nfs.c | |
parent | 67966e088b0c7dc926f4ce19565ebf208e18d058 (diff) | |
parent | 33e2a4227ddff7c18921ac175fae3ab0e3ff8a76 (diff) | |
download | linux-11126c611e10abb18b6f1ed0300c0548c3906b54.tar.bz2 |
Merge branch 'akpm' (Andrew's patch-bomb)
Merge misc patches from Andrew Morton:
"The MM tree is rather stuck while I wait to find out what the heck is
happening with sched/numa. Probably I'll need to route around all the
code which was added to -next, sigh.
So this is "everything else", or at least most of it - other small
bits are still awaiting resolutions of various kinds."
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (180 commits)
lib/decompress.c add __init to decompress_method and data
kernel/resource.c: fix stack overflow in __reserve_region_with_split()
omfs: convert to use beXX_add_cpu()
taskstats: cgroupstats_user_cmd() may leak on error
aoe: update aoe-internal version number to 50
aoe: update documentation to better reflect aoe-plus-udev usage
aoe: remove unused code
aoe: make dynamic block minor numbers the default
aoe: update and specify AoE address guards and error messages
aoe: retain static block device numbers for backwards compatibility
aoe: support more AoE addresses with dynamic block device minor numbers
aoe: update documentation with new URL and VM settings reference
aoe: update copyright year in touched files
aoe: update internal version number to 49
aoe: remove unused code and add cosmetic improvements
aoe: increase net_device reference count while using it
aoe: associate frames with the AoE storage target
aoe: disallow unsupported AoE minor addresses
aoe: do revalidation steps in order
aoe: failover remote interface based on aoe_deadsecs parameter
...
Diffstat (limited to 'fs/fat/nfs.c')
-rw-r--r-- | fs/fat/nfs.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/fs/fat/nfs.c b/fs/fat/nfs.c new file mode 100644 index 000000000000..ef4b5faba87b --- /dev/null +++ b/fs/fat/nfs.c @@ -0,0 +1,101 @@ +/* fs/fat/nfs.c + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <linux/exportfs.h> +#include "fat.h" + +/** + * Look up a directory inode given its starting cluster. + */ +static struct inode *fat_dget(struct super_block *sb, int i_logstart) +{ + struct msdos_sb_info *sbi = MSDOS_SB(sb); + struct hlist_head *head; + struct hlist_node *_p; + struct msdos_inode_info *i; + struct inode *inode = NULL; + + head = sbi->dir_hashtable + fat_dir_hash(i_logstart); + spin_lock(&sbi->dir_hash_lock); + hlist_for_each_entry(i, _p, head, i_dir_hash) { + BUG_ON(i->vfs_inode.i_sb != sb); + if (i->i_logstart != i_logstart) + continue; + inode = igrab(&i->vfs_inode); + if (inode) + break; + } + spin_unlock(&sbi->dir_hash_lock); + return inode; +} + +static struct inode *fat_nfs_get_inode(struct super_block *sb, + u64 ino, u32 generation) +{ + struct inode *inode; + + if ((ino < MSDOS_ROOT_INO) || (ino == MSDOS_FSINFO_INO)) + return NULL; + + inode = ilookup(sb, ino); + if (inode && generation && (inode->i_generation != generation)) { + iput(inode); + inode = NULL; + } + + return inode; +} + +/** + * Map a NFS file handle to a corresponding dentry. + * The dentry may or may not be connected to the filesystem root. + */ +struct dentry *fat_fh_to_dentry(struct super_block *sb, struct fid *fid, + int fh_len, int fh_type) +{ + return generic_fh_to_dentry(sb, fid, fh_len, fh_type, + fat_nfs_get_inode); +} + +/* + * Find the parent for a file specified by NFS handle. + * This requires that the handle contain the i_ino of the parent. + */ +struct dentry *fat_fh_to_parent(struct super_block *sb, struct fid *fid, + int fh_len, int fh_type) +{ + return generic_fh_to_parent(sb, fid, fh_len, fh_type, + fat_nfs_get_inode); +} + +/* + * Find the parent for a directory that is not currently connected to + * the filesystem root. + * + * On entry, the caller holds child_dir->d_inode->i_mutex. + */ +struct dentry *fat_get_parent(struct dentry *child_dir) +{ + struct super_block *sb = child_dir->d_sb; + struct buffer_head *bh = NULL; + struct msdos_dir_entry *de; + struct inode *parent_inode = NULL; + + if (!fat_get_dotdot_entry(child_dir->d_inode, &bh, &de)) { + int parent_logstart = fat_get_start(MSDOS_SB(sb), de); + parent_inode = fat_dget(sb, parent_logstart); + } + brelse(bh); + + return d_obtain_alias(parent_inode); +} |