From d0adde574b8487ef30f69e2d08bba769e4be513f Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Thu, 26 Mar 2009 17:49:56 +0000 Subject: Add a strictatime mount option Add support for explicitly requesting full atime updates. This makes it possible for kernels to default to relatime but still allow userspace to override it. Signed-off-by: Matthew Garrett Signed-off-by: Linus Torvalds --- fs/namespace.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'fs/namespace.c') diff --git a/fs/namespace.c b/fs/namespace.c index 06f8e63f6cb1..d0659ec291c9 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -780,6 +780,7 @@ static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt) { MNT_NOATIME, ",noatime" }, { MNT_NODIRATIME, ",nodiratime" }, { MNT_RELATIME, ",relatime" }, + { MNT_STRICTATIME, ",strictatime" }, { 0, NULL } }; const struct proc_fs_info *fs_infop; @@ -1932,11 +1933,14 @@ long do_mount(char *dev_name, char *dir_name, char *type_page, mnt_flags |= MNT_NODIRATIME; if (flags & MS_RELATIME) mnt_flags |= MNT_RELATIME; + if (flags & MS_STRICTATIME) + mnt_flags &= ~(MNT_RELATIME | MNT_NOATIME); if (flags & MS_RDONLY) mnt_flags |= MNT_READONLY; flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE | - MS_NOATIME | MS_NODIRATIME | MS_RELATIME| MS_KERNMOUNT); + MS_NOATIME | MS_NODIRATIME | MS_RELATIME| MS_KERNMOUNT | + MS_STRICTATIME); /* ... and get the mountpoint */ retval = kern_path(dir_name, LOOKUP_FOLLOW, &path); -- cgit v1.2.2 From 0a1c01c9477602ee8b44548a9405b2c1d587b5a2 Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Thu, 26 Mar 2009 17:53:14 +0000 Subject: Make relatime default Change the default behaviour of the kernel to use relatime for all filesystems. This can be overridden with the "strictatime" mount option. Signed-off-by: Matthew Garrett Signed-off-by: Linus Torvalds --- fs/namespace.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'fs/namespace.c') diff --git a/fs/namespace.c b/fs/namespace.c index d0659ec291c9..f0e753097353 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1920,6 +1920,9 @@ long do_mount(char *dev_name, char *dir_name, char *type_page, if (data_page) ((char *)data_page)[PAGE_SIZE - 1] = 0; + /* Default to relatime */ + mnt_flags |= MNT_RELATIME; + /* Separate the per-mountpoint flags */ if (flags & MS_NOSUID) mnt_flags |= MNT_NOSUID; @@ -1931,8 +1934,6 @@ long do_mount(char *dev_name, char *dir_name, char *type_page, mnt_flags |= MNT_NOATIME; if (flags & MS_NODIRATIME) mnt_flags |= MNT_NODIRATIME; - if (flags & MS_RELATIME) - mnt_flags |= MNT_RELATIME; if (flags & MS_STRICTATIME) mnt_flags &= ~(MNT_RELATIME | MNT_NOATIME); if (flags & MS_RDONLY) -- cgit v1.2.2 From a3ec947c85ec339884b30ef6a08133e9311fdae1 Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Wed, 4 Mar 2009 12:06:34 -0800 Subject: vfs: simple_set_mnt() should return void simple_set_mnt() is defined as returning 'int' but always returns 0. Callers assume simple_set_mnt() never fails and don't properly cleanup if it were to _ever_ fail. For instance, get_sb_single() and get_sb_nodev() should: up_write(sb->s_unmount); deactivate_super(sb); if simple_set_mnt() fails. Since simple_set_mnt() never fails, would be cleaner if it did not return anything. [akpm@linux-foundation.org: fix build] Signed-off-by: Sukadev Bhattiprolu Acked-by: Serge Hallyn Cc: Al Viro Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Al Viro --- fs/namespace.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/namespace.c') diff --git a/fs/namespace.c b/fs/namespace.c index 06f8e63f6cb1..2432ca6bb223 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -397,11 +397,10 @@ static void __mnt_unmake_readonly(struct vfsmount *mnt) spin_unlock(&vfsmount_lock); } -int simple_set_mnt(struct vfsmount *mnt, struct super_block *sb) +void simple_set_mnt(struct vfsmount *mnt, struct super_block *sb) { mnt->mnt_sb = sb; mnt->mnt_root = dget(sb->s_root); - return 0; } EXPORT_SYMBOL(simple_set_mnt); -- cgit v1.2.2 From f8ef3ed2bebd2c4cb9ece92efa185d7aead8831a Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 30 Mar 2009 20:36:33 -0400 Subject: Get rid of bumping fs_struct refcount in pivot_root(2) Not because execve races with _that_ are serious - we really need a situation when final drop of fs_struct refcount is done by something that used to have it as current->fs. Signed-off-by: Al Viro --- fs/namespace.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) (limited to 'fs/namespace.c') diff --git a/fs/namespace.c b/fs/namespace.c index 0a42e0e96027..f7ec283ccfbb 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2131,25 +2131,33 @@ static void chroot_fs_refs(struct path *old_root, struct path *new_root) { struct task_struct *g, *p; struct fs_struct *fs; + int count = 0; read_lock(&tasklist_lock); do_each_thread(g, p) { task_lock(p); fs = p->fs; if (fs) { - atomic_inc(&fs->count); - task_unlock(p); + write_lock(&fs->lock); if (fs->root.dentry == old_root->dentry - && fs->root.mnt == old_root->mnt) - set_fs_root(fs, new_root); + && fs->root.mnt == old_root->mnt) { + path_get(new_root); + fs->root = *new_root; + count++; + } if (fs->pwd.dentry == old_root->dentry - && fs->pwd.mnt == old_root->mnt) - set_fs_pwd(fs, new_root); - put_fs_struct(fs); - } else - task_unlock(p); + && fs->pwd.mnt == old_root->mnt) { + path_get(new_root); + fs->pwd = *new_root; + count++; + } + write_unlock(&fs->lock); + } + task_unlock(p); } while_each_thread(g, p); read_unlock(&tasklist_lock); + while (count--) + path_put(old_root); } /* -- cgit v1.2.2 From 3e93cd671813e204c258f1e6c797959920cf7772 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 29 Mar 2009 19:00:13 -0400 Subject: Take fs_struct handling to new file (fs/fs_struct.c) Pure code move; two new helper functions for nfsd and daemonize (unshare_fs_struct() and daemonize_fs_struct() resp.; for now - the same code as used to be in callers). unshare_fs_struct() exported (for nfsd, as copy_fs_struct()/exit_fs() used to be), copy_fs_struct() and exit_fs() don't need exports anymore. Signed-off-by: Al Viro --- fs/namespace.c | 68 ---------------------------------------------------------- 1 file changed, 68 deletions(-) (limited to 'fs/namespace.c') diff --git a/fs/namespace.c b/fs/namespace.c index f7ec283ccfbb..1e56303c718e 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2092,74 +2092,6 @@ out1: return retval; } -/* - * Replace the fs->{rootmnt,root} with {mnt,dentry}. Put the old values. - * It can block. Requires the big lock held. - */ -void set_fs_root(struct fs_struct *fs, struct path *path) -{ - struct path old_root; - - write_lock(&fs->lock); - old_root = fs->root; - fs->root = *path; - path_get(path); - write_unlock(&fs->lock); - if (old_root.dentry) - path_put(&old_root); -} - -/* - * Replace the fs->{pwdmnt,pwd} with {mnt,dentry}. Put the old values. - * It can block. Requires the big lock held. - */ -void set_fs_pwd(struct fs_struct *fs, struct path *path) -{ - struct path old_pwd; - - write_lock(&fs->lock); - old_pwd = fs->pwd; - fs->pwd = *path; - path_get(path); - write_unlock(&fs->lock); - - if (old_pwd.dentry) - path_put(&old_pwd); -} - -static void chroot_fs_refs(struct path *old_root, struct path *new_root) -{ - struct task_struct *g, *p; - struct fs_struct *fs; - int count = 0; - - read_lock(&tasklist_lock); - do_each_thread(g, p) { - task_lock(p); - fs = p->fs; - if (fs) { - write_lock(&fs->lock); - if (fs->root.dentry == old_root->dentry - && fs->root.mnt == old_root->mnt) { - path_get(new_root); - fs->root = *new_root; - count++; - } - if (fs->pwd.dentry == old_root->dentry - && fs->pwd.mnt == old_root->mnt) { - path_get(new_root); - fs->pwd = *new_root; - count++; - } - write_unlock(&fs->lock); - } - task_unlock(p); - } while_each_thread(g, p); - read_unlock(&tasklist_lock); - while (count--) - path_put(old_root); -} - /* * pivot_root Semantics: * Moves the root file system of the current process to the directory put_old, -- cgit v1.2.2 From 5ad4e53bd5406ee214ddc5a41f03f779b8b2d526 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 29 Mar 2009 19:50:06 -0400 Subject: Get rid of indirect include of fs_struct.h Don't pull it in sched.h; very few files actually need it and those can include directly. sched.h itself only needs forward declaration of struct fs_struct; Signed-off-by: Al Viro --- fs/namespace.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/namespace.c') diff --git a/fs/namespace.c b/fs/namespace.c index 1e56303c718e..c6f54e4c4290 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include "pnode.h" -- cgit v1.2.2