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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-07 19:56:33 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-07 19:56:33 +0300
commitb4a45f5fe8078bfc10837dbd5b98735058bc4698 (patch)
treedf6f13a27610a3ec7eb4a661448cd779a8f84c79 /Documentation/filesystems/Locking
parent01539ba2a706ab7d35fc0667dff919ade7f87d63 (diff)
parentb3e19d924b6eaf2ca7d22cba99a517c5171007b6 (diff)
downloadlinux-b4a45f5fe8078bfc10837dbd5b98735058bc4698.tar.xz
Merge branch 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin
* 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin: (57 commits) fs: scale mntget/mntput fs: rename vfsmount counter helpers fs: implement faster dentry memcmp fs: prefetch inode data in dcache lookup fs: improve scalability of pseudo filesystems fs: dcache per-inode inode alias locking fs: dcache per-bucket dcache hash locking bit_spinlock: add required includes kernel: add bl_list xfs: provide simple rcu-walk ACL implementation btrfs: provide simple rcu-walk ACL implementation ext2,3,4: provide simple rcu-walk ACL implementation fs: provide simple rcu-walk generic_check_acl implementation fs: provide rcu-walk aware permission i_ops fs: rcu-walk aware d_revalidate method fs: cache optimise dentry and inode for rcu-walk fs: dcache reduce branches in lookup path fs: dcache remove d_mounted fs: fs_struct use seqlock fs: rcu-walk for path lookup ...
Diffstat (limited to 'Documentation/filesystems/Locking')
-rw-r--r--Documentation/filesystems/Locking29
1 files changed, 16 insertions, 13 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 33fa3e5d38fd..977d8919cc69 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -9,22 +9,25 @@ be able to use diff(1).
--------------------------- dentry_operations --------------------------
prototypes:
- int (*d_revalidate)(struct dentry *, int);
- int (*d_hash) (struct dentry *, struct qstr *);
- int (*d_compare) (struct dentry *, struct qstr *, struct qstr *);
+ int (*d_revalidate)(struct dentry *, struct nameidata *);
+ int (*d_hash)(const struct dentry *, const struct inode *,
+ struct qstr *);
+ int (*d_compare)(const struct dentry *, const struct inode *,
+ const struct dentry *, const struct inode *,
+ unsigned int, const char *, const struct qstr *);
int (*d_delete)(struct dentry *);
void (*d_release)(struct dentry *);
void (*d_iput)(struct dentry *, struct inode *);
char *(*d_dname)((struct dentry *dentry, char *buffer, int buflen);
locking rules:
- dcache_lock rename_lock ->d_lock may block
-d_revalidate: no no no yes
-d_hash no no no yes
-d_compare: no yes no no
-d_delete: yes no yes no
-d_release: no no no yes
-d_iput: no no no yes
+ rename_lock ->d_lock may block rcu-walk
+d_revalidate: no no yes (ref-walk) maybe
+d_hash no no no maybe
+d_compare: yes no no maybe
+d_delete: no yes no no
+d_release: no no yes no
+d_iput: no no yes no
d_dname: no no no no
--------------------------- inode_operations ---------------------------
@@ -44,8 +47,8 @@ ata *);
void * (*follow_link) (struct dentry *, struct nameidata *);
void (*put_link) (struct dentry *, struct nameidata *, void *);
void (*truncate) (struct inode *);
- int (*permission) (struct inode *, int, struct nameidata *);
- int (*check_acl)(struct inode *, int);
+ int (*permission) (struct inode *, int, unsigned int);
+ int (*check_acl)(struct inode *, int, unsigned int);
int (*setattr) (struct dentry *, struct iattr *);
int (*getattr) (struct vfsmount *, struct dentry *, struct kstat *);
int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
@@ -73,7 +76,7 @@ follow_link: no
put_link: no
truncate: yes (see below)
setattr: yes
-permission: no
+permission: no (may not block if called in rcu-walk mode)
check_acl: no
getattr: no
setxattr: yes