diff options
Diffstat (limited to 'fs/namei.c')
-rw-r--r-- | fs/namei.c | 84 |
1 files changed, 53 insertions, 31 deletions
@@ -104,7 +104,7 @@ */ /* * [Sep 2001 AV] Single-semaphore locking scheme (kudos to David Holland) - * implemented. Let's see if raised priority of ->s_vfs_rename_sem gives + * implemented. Let's see if raised priority of ->s_vfs_rename_mutex gives * any extra contention... */ @@ -546,6 +546,22 @@ struct path { struct dentry *dentry; }; +static inline void dput_path(struct path *path, struct nameidata *nd) +{ + dput(path->dentry); + if (path->mnt != nd->mnt) + mntput(path->mnt); +} + +static inline void path_to_nameidata(struct path *path, struct nameidata *nd) +{ + dput(nd->dentry); + if (nd->mnt != path->mnt) + mntput(nd->mnt); + nd->mnt = path->mnt; + nd->dentry = path->dentry; +} + static __always_inline int __do_follow_link(struct path *path, struct nameidata *nd) { int error; @@ -555,8 +571,11 @@ static __always_inline int __do_follow_link(struct path *path, struct nameidata touch_atime(path->mnt, dentry); nd_set_link(nd, NULL); - if (path->mnt == nd->mnt) - mntget(path->mnt); + if (path->mnt != nd->mnt) { + path_to_nameidata(path, nd); + dget(dentry); + } + mntget(path->mnt); cookie = dentry->d_inode->i_op->follow_link(dentry, nd); error = PTR_ERR(cookie); if (!IS_ERR(cookie)) { @@ -573,22 +592,6 @@ static __always_inline int __do_follow_link(struct path *path, struct nameidata return error; } -static inline void dput_path(struct path *path, struct nameidata *nd) -{ - dput(path->dentry); - if (path->mnt != nd->mnt) - mntput(path->mnt); -} - -static inline void path_to_nameidata(struct path *path, struct nameidata *nd) -{ - dput(nd->dentry); - if (nd->mnt != path->mnt) - mntput(nd->mnt); - nd->mnt = path->mnt; - nd->dentry = path->dentry; -} - /* * This limits recursive symlink follows to 8, while * limiting consecutive symlinks to 40. @@ -1353,6 +1356,7 @@ static int may_delete(struct inode *dir,struct dentry *victim,int isdir) return -ENOENT; BUG_ON(victim->d_parent->d_inode != dir); + audit_inode_child(victim->d_name.name, victim->d_inode, dir->i_ino); error = permission(dir,MAY_WRITE | MAY_EXEC, NULL); if (error) @@ -1422,7 +1426,7 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2) return NULL; } - down(&p1->d_inode->i_sb->s_vfs_rename_sem); + mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex); for (p = p1; p->d_parent != p; p = p->d_parent) { if (p->d_parent == p2) { @@ -1450,7 +1454,7 @@ void unlock_rename(struct dentry *p1, struct dentry *p2) mutex_unlock(&p1->d_inode->i_mutex); if (p1 != p2) { mutex_unlock(&p2->d_inode->i_mutex); - up(&p1->d_inode->i_sb->s_vfs_rename_sem); + mutex_unlock(&p1->d_inode->i_sb->s_vfs_rename_mutex); } } @@ -1472,7 +1476,7 @@ int vfs_create(struct inode *dir, struct dentry *dentry, int mode, DQUOT_INIT(dir); error = dir->i_op->create(dir, dentry, mode, nd); if (!error) - fsnotify_create(dir, dentry->d_name.name); + fsnotify_create(dir, dentry); return error; } @@ -1628,6 +1632,12 @@ do_last: goto exit; } + if (IS_ERR(nd->intent.open.file)) { + mutex_unlock(&dir->d_inode->i_mutex); + error = PTR_ERR(nd->intent.open.file); + goto exit_dput; + } + /* Negative dentry, just create the file */ if (!path.dentry->d_inode) { if (!IS_POSIXACL(dir->d_inode)) @@ -1793,7 +1803,7 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) DQUOT_INIT(dir); error = dir->i_op->mknod(dir, dentry, mode, dev); if (!error) - fsnotify_create(dir, dentry->d_name.name); + fsnotify_create(dir, dentry); return error; } @@ -1870,7 +1880,7 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) DQUOT_INIT(dir); error = dir->i_op->mkdir(dir, dentry, mode); if (!error) - fsnotify_mkdir(dir, dentry->d_name.name); + fsnotify_mkdir(dir, dentry); return error; } @@ -2133,7 +2143,7 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, i DQUOT_INIT(dir); error = dir->i_op->symlink(dir, dentry, oldname); if (!error) - fsnotify_create(dir, dentry->d_name.name); + fsnotify_create(dir, dentry); return error; } @@ -2210,7 +2220,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de error = dir->i_op->link(old_dentry, dir, new_dentry); mutex_unlock(&old_dentry->d_inode->i_mutex); if (!error) - fsnotify_create(dir, new_dentry->d_name.name); + fsnotify_create(dir, new_dentry); return error; } @@ -2277,17 +2287,17 @@ asmlinkage long sys_link(const char __user *oldname, const char __user *newname) * a) we can get into loop creation. Check is done in is_subdir(). * b) race potential - two innocent renames can create a loop together. * That's where 4.4 screws up. Current fix: serialization on - * sb->s_vfs_rename_sem. We might be more accurate, but that's another + * sb->s_vfs_rename_mutex. We might be more accurate, but that's another * story. * c) we have to lock _three_ objects - parents and victim (if it exists). * And that - after we got ->i_mutex on parents (until then we don't know * whether the target exists). Solution: try to be smart with locking * order for inodes. We rely on the fact that tree topology may change - * only under ->s_vfs_rename_sem _and_ that parent of the object we + * only under ->s_vfs_rename_mutex _and_ that parent of the object we * move will be locked. Thus we can rank directories by the tree * (ancestors first) and rank all non-directories after them. * That works since everybody except rename does "lock parent, lookup, - * lock child" and rename is under ->s_vfs_rename_sem. + * lock child" and rename is under ->s_vfs_rename_mutex. * HOWEVER, it relies on the assumption that any object with ->lookup() * has no more than 1 dentry. If "hybrid" objects will ever appear, * we'd better make sure that there's no link(2) for them. @@ -2621,16 +2631,27 @@ int __page_symlink(struct inode *inode, const char *symname, int len, int err = -ENOMEM; char *kaddr; +retry: page = find_or_create_page(mapping, 0, gfp_mask); if (!page) goto fail; err = mapping->a_ops->prepare_write(NULL, page, 0, len-1); + if (err == AOP_TRUNCATED_PAGE) { + page_cache_release(page); + goto retry; + } if (err) goto fail_map; kaddr = kmap_atomic(page, KM_USER0); memcpy(kaddr, symname, len-1); kunmap_atomic(kaddr, KM_USER0); - mapping->a_ops->commit_write(NULL, page, 0, len-1); + err = mapping->a_ops->commit_write(NULL, page, 0, len-1); + if (err == AOP_TRUNCATED_PAGE) { + page_cache_release(page); + goto retry; + } + if (err) + goto fail_map; /* * Notice that we are _not_ going to block here - end of page is * unmapped, so this will only try to map the rest of page, see @@ -2640,7 +2661,8 @@ int __page_symlink(struct inode *inode, const char *symname, int len, */ if (!PageUptodate(page)) { err = mapping->a_ops->readpage(NULL, page); - wait_on_page_locked(page); + if (err != AOP_TRUNCATED_PAGE) + wait_on_page_locked(page); } else { unlock_page(page); } |