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| author | Nick Piggin <npiggin@kernel.dk> | 2011-01-07 17:49:57 +1100 |
|---|---|---|
| committer | Nick Piggin <npiggin@kernel.dk> | 2011-01-07 17:50:29 +1100 |
| commit | 34286d6662308d82aed891852d04c7c3a2649b16 (patch) | |
| tree | c4b7311404d302e7cb94df7a4690298e1059910a /fs/proc | |
| parent | 44a7d7a878c9cbb74f236ea755b25b6b2e26a9a9 (diff) | |
| download | linux-34286d6662308d82aed891852d04c7c3a2649b16.tar.gz linux-34286d6662308d82aed891852d04c7c3a2649b16.tar.bz2 linux-34286d6662308d82aed891852d04c7c3a2649b16.zip | |
fs: rcu-walk aware d_revalidate method
Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Diffstat (limited to 'fs/proc')
| -rw-r--r-- | fs/proc/base.c | 33 | ||||
| -rw-r--r-- | fs/proc/proc_sysctl.c | 3 |
2 files changed, 29 insertions, 7 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index 85f0a80912aa..dc5b2fcadc3b 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1719,10 +1719,16 @@ static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat */ static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) { - struct inode *inode = dentry->d_inode; - struct task_struct *task = get_proc_task(inode); + struct inode *inode; + struct task_struct *task; const struct cred *cred; + if (nd && nd->flags & LOOKUP_RCU) + return -ECHILD; + + inode = dentry->d_inode; + task = get_proc_task(inode); + if (task) { if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || task_dumpable(task)) { @@ -1888,12 +1894,19 @@ static int proc_fd_link(struct inode *inode, struct path *path) static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) { - struct inode *inode = dentry->d_inode; - struct task_struct *task = get_proc_task(inode); - int fd = proc_fd(inode); + struct inode *inode; + struct task_struct *task; + int fd; struct files_struct *files; const struct cred *cred; + if (nd && nd->flags & LOOKUP_RCU) + return -ECHILD; + + inode = dentry->d_inode; + task = get_proc_task(inode); + fd = proc_fd(inode); + if (task) { files = get_files_struct(task); if (files) { @@ -2563,8 +2576,14 @@ static const struct pid_entry proc_base_stuff[] = { */ static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd) { - struct inode *inode = dentry->d_inode; - struct task_struct *task = get_proc_task(inode); + struct inode *inode; + struct task_struct *task; + + if (nd->flags & LOOKUP_RCU) + return -ECHILD; + + inode = dentry->d_inode; + task = get_proc_task(inode); if (task) { put_task_struct(task); return 1; diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 35efd85a4d32..c9097f43b425 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -5,6 +5,7 @@ #include <linux/sysctl.h> #include <linux/proc_fs.h> #include <linux/security.h> +#include <linux/namei.h> #include "internal.h" static const struct dentry_operations proc_sys_dentry_operations; @@ -389,6 +390,8 @@ static const struct inode_operations proc_sys_dir_operations = { static int proc_sys_revalidate(struct dentry *dentry, struct nameidata *nd) { + if (nd->flags & LOOKUP_RCU) + return -ECHILD; return !PROC_I(dentry->d_inode)->sysctl->unregistering; } |