提交 32e51f14 编写于 作者: L Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (25 commits)
  cifs: remove unnecessary dentry_unhash on rmdir/rename_dir
  ocfs2: remove unnecessary dentry_unhash on rmdir/rename_dir
  exofs: remove unnecessary dentry_unhash on rmdir/rename_dir
  nfs: remove unnecessary dentry_unhash on rmdir/rename_dir
  ext2: remove unnecessary dentry_unhash on rmdir/rename_dir
  ext3: remove unnecessary dentry_unhash on rmdir/rename_dir
  ext4: remove unnecessary dentry_unhash on rmdir/rename_dir
  btrfs: remove unnecessary dentry_unhash in rmdir/rename_dir
  ceph: remove unnecessary dentry_unhash calls
  vfs: clean up vfs_rename_other
  vfs: clean up vfs_rename_dir
  vfs: clean up vfs_rmdir
  vfs: fix vfs_rename_dir for FS_RENAME_DOES_D_MOVE filesystems
  libfs: drop unneeded dentry_unhash
  vfs: update dentry_unhash() comment
  vfs: push dentry_unhash on rename_dir into file systems
  vfs: push dentry_unhash on rmdir into file systems
  vfs: remove dget() from dentry_unhash()
  vfs: dentry_unhash immediately prior to rmdir
  vfs: Block mmapped writes while the fs is frozen
  ...
......@@ -814,6 +814,7 @@ int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
{
dentry_unhash(d);
return v9fs_remove(i, d, 1);
}
......@@ -839,6 +840,9 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct p9_fid *newdirfid;
struct p9_wstat wstat;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
P9_DPRINTK(P9_DEBUG_VFS, "\n");
retval = 0;
old_inode = old_dentry->d_inode;
......
......@@ -47,7 +47,7 @@ config FS_POSIX_ACL
def_bool n
config EXPORTFS
bool
tristate
config FILE_LOCKING
bool "Enable POSIX file locking API" if EXPERT
......
......@@ -320,6 +320,8 @@ affs_rmdir(struct inode *dir, struct dentry *dentry)
dentry->d_inode->i_ino,
(int)dentry->d_name.len, dentry->d_name.name);
dentry_unhash(dentry);
return affs_remove_header(dentry);
}
......@@ -417,6 +419,9 @@ affs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct buffer_head *bh = NULL;
int retval;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
pr_debug("AFFS: rename(old=%u,\"%*s\" to new=%u,\"%*s\")\n",
(u32)old_dir->i_ino, (int)old_dentry->d_name.len, old_dentry->d_name.name,
(u32)new_dir->i_ino, (int)new_dentry->d_name.len, new_dentry->d_name.name);
......
......@@ -845,6 +845,8 @@ static int afs_rmdir(struct inode *dir, struct dentry *dentry)
_enter("{%x:%u},{%s}",
dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name);
dentry_unhash(dentry);
ret = -ENAMETOOLONG;
if (dentry->d_name.len >= AFSNAMEMAX)
goto error;
......@@ -1146,6 +1148,9 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct key *key;
int ret;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
vnode = AFS_FS_I(old_dentry->d_inode);
orig_dvnode = AFS_FS_I(old_dir);
new_dvnode = AFS_FS_I(new_dir);
......
......@@ -583,6 +583,8 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
if (!autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN))
return -EACCES;
dentry_unhash(dentry);
if (atomic_dec_and_test(&ino->count)) {
p_ino = autofs4_dentry_ino(dentry->d_parent);
if (p_ino && dentry->d_parent != dentry)
......
......@@ -224,6 +224,9 @@ static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct bfs_sb_info *info;
int error = -ENOENT;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
old_bh = new_bh = NULL;
old_inode = old_dentry->d_inode;
if (S_ISDIR(old_inode->i_mode))
......
......@@ -2331,24 +2331,26 @@ EXPORT_SYMBOL(block_commit_write);
* page lock we can determine safely if the page is beyond EOF. If it is not
* beyond EOF, then the page is guaranteed safe against truncation until we
* unlock the page.
*
* Direct callers of this function should call vfs_check_frozen() so that page
* fault does not busyloop until the fs is thawed.
*/
int
block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
get_block_t get_block)
int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
get_block_t get_block)
{
struct page *page = vmf->page;
struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
unsigned long end;
loff_t size;
int ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
int ret;
lock_page(page);
size = i_size_read(inode);
if ((page->mapping != inode->i_mapping) ||
(page_offset(page) > size)) {
/* page got truncated out from underneath us */
unlock_page(page);
goto out;
/* We overload EFAULT to mean page got truncated */
ret = -EFAULT;
goto out_unlock;
}
/* page is wholly or partially inside EOF */
......@@ -2361,18 +2363,41 @@ block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
if (!ret)
ret = block_commit_write(page, 0, end);
if (unlikely(ret)) {
unlock_page(page);
if (ret == -ENOMEM)
ret = VM_FAULT_OOM;
else /* -ENOSPC, -EIO, etc */
ret = VM_FAULT_SIGBUS;
} else
ret = VM_FAULT_LOCKED;
out:
if (unlikely(ret < 0))
goto out_unlock;
/*
* Freezing in progress? We check after the page is marked dirty and
* with page lock held so if the test here fails, we are sure freezing
* code will wait during syncing until the page fault is done - at that
* point page will be dirty and unlocked so freezing code will write it
* and writeprotect it again.
*/
set_page_dirty(page);
if (inode->i_sb->s_frozen != SB_UNFROZEN) {
ret = -EAGAIN;
goto out_unlock;
}
return 0;
out_unlock:
unlock_page(page);
return ret;
}
EXPORT_SYMBOL(__block_page_mkwrite);
int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
get_block_t get_block)
{
int ret;
struct super_block *sb = vma->vm_file->f_path.dentry->d_inode->i_sb;
/*
* This check is racy but catches the common case. The check in
* __block_page_mkwrite() is reliable.
*/
vfs_check_frozen(sb, SB_FREEZE_WRITE);
ret = __block_page_mkwrite(vma, vmf, get_block);
return block_page_mkwrite_return(ret);
}
EXPORT_SYMBOL(block_page_mkwrite);
/*
......
......@@ -336,6 +336,8 @@ static int coda_rmdir(struct inode *dir, struct dentry *de)
int len = de->d_name.len;
int error;
dentry_unhash(de);
error = venus_rmdir(dir->i_sb, coda_i2f(dir), name, len);
if (!error) {
/* VFS may delete the child */
......@@ -359,6 +361,9 @@ static int coda_rename(struct inode *old_dir, struct dentry *old_dentry,
int new_length = new_dentry->d_name.len;
int error;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
error = venus_rename(old_dir->i_sb, coda_i2f(old_dir),
coda_i2f(new_dir), old_length, new_length,
(const char *) old_name, (const char *)new_name);
......
......@@ -1359,6 +1359,8 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry)
struct module *subsys_owner = NULL, *dead_item_owner = NULL;
int ret;
dentry_unhash(dentry);
if (dentry->d_parent == configfs_sb->s_root)
return -EPERM;
......
......@@ -521,6 +521,8 @@ static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
struct dentry *lower_dir_dentry;
int rc;
dentry_unhash(dentry);
lower_dentry = ecryptfs_dentry_to_lower(dentry);
dget(dentry);
lower_dir_dentry = lock_parent(lower_dentry);
......@@ -571,6 +573,9 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct dentry *lower_new_dir_dentry;
struct dentry *trap = NULL;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
dget(lower_old_dentry);
......
......@@ -326,6 +326,8 @@ static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
struct fat_slot_info sinfo;
int err;
dentry_unhash(dentry);
lock_super(sb);
/*
* Check whether the directory is not in use, then check
......@@ -457,6 +459,9 @@ static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
old_inode = old_dentry->d_inode;
new_inode = new_dentry->d_inode;
if (new_inode && S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
err = fat_scan(old_dir, old_name, &old_sinfo);
if (err) {
err = -EIO;
......
......@@ -824,6 +824,8 @@ static int vfat_rmdir(struct inode *dir, struct dentry *dentry)
struct fat_slot_info sinfo;
int err;
dentry_unhash(dentry);
lock_super(sb);
err = fat_dir_empty(inode);
......@@ -931,6 +933,9 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
int err, is_dir, update_dotdot, corrupt = 0;
struct super_block *sb = old_dir->i_sb;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
old_inode = old_dentry->d_inode;
new_inode = new_dentry->d_inode;
......
......@@ -667,6 +667,8 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry)
if (IS_ERR(req))
return PTR_ERR(req);
dentry_unhash(entry);
req->in.h.opcode = FUSE_RMDIR;
req->in.h.nodeid = get_node_id(dir);
req->in.numargs = 1;
......@@ -691,6 +693,10 @@ static int fuse_rename(struct inode *olddir, struct dentry *oldent,
struct fuse_rename_in inarg;
struct fuse_conn *fc = get_fuse_conn(olddir);
struct fuse_req *req = fuse_get_req(fc);
if (newent->d_inode && S_ISDIR(newent->d_inode->i_mode))
dentry_unhash(newent);
if (IS_ERR(req))
return PTR_ERR(req);
......
......@@ -253,6 +253,9 @@ static int hfs_remove(struct inode *dir, struct dentry *dentry)
struct inode *inode = dentry->d_inode;
int res;
if (S_ISDIR(inode->i_mode))
dentry_unhash(dentry);
if (S_ISDIR(inode->i_mode) && inode->i_size != 2)
return -ENOTEMPTY;
res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
......@@ -283,6 +286,9 @@ static int hfs_rename(struct inode *old_dir, struct dentry *old_dentry,
/* Unlink destination if it already exists */
if (new_dentry->d_inode) {
if (S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
res = hfs_remove(new_dir, new_dentry);
if (res)
return res;
......
......@@ -370,6 +370,8 @@ static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
struct inode *inode = dentry->d_inode;
int res;
dentry_unhash(dentry);
if (inode->i_size != 2)
return -ENOTEMPTY;
......@@ -467,10 +469,12 @@ static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
/* Unlink destination if it already exists */
if (new_dentry->d_inode) {
if (S_ISDIR(new_dentry->d_inode->i_mode))
if (S_ISDIR(new_dentry->d_inode->i_mode)) {
dentry_unhash(new_dentry);
res = hfsplus_rmdir(new_dir, new_dentry);
else
} else {
res = hfsplus_unlink(new_dir, new_dentry);
}
if (res)
return res;
}
......
......@@ -683,6 +683,8 @@ int hostfs_rmdir(struct inode *ino, struct dentry *dentry)
char *file;
int err;
dentry_unhash(dentry);
if ((file = dentry_name(dentry)) == NULL)
return -ENOMEM;
err = do_rmdir(file);
......@@ -736,6 +738,9 @@ int hostfs_rename(struct inode *from_ino, struct dentry *from,
char *from_name, *to_name;
int err;
if (to->d_inode && S_ISDIR(to->d_inode->i_mode))
dentry_unhash(to);
if ((from_name = dentry_name(from)) == NULL)
return -ENOMEM;
if ((to_name = dentry_name(to)) == NULL) {
......
......@@ -395,7 +395,6 @@ static int hpfs_unlink(struct inode *dir, struct dentry *dentry)
dentry_unhash(dentry);
if (!d_unhashed(dentry)) {
dput(dentry);
hpfs_unlock(dir->i_sb);
return -ENOSPC;
}
......@@ -403,7 +402,6 @@ static int hpfs_unlink(struct inode *dir, struct dentry *dentry)
!S_ISREG(inode->i_mode) ||
get_write_access(inode)) {
d_rehash(dentry);
dput(dentry);
} else {
struct iattr newattrs;
/*printk("HPFS: truncating file before delete.\n");*/
......@@ -411,7 +409,6 @@ static int hpfs_unlink(struct inode *dir, struct dentry *dentry)
newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME;
err = notify_change(dentry, &newattrs);
put_write_access(inode);
dput(dentry);
if (!err)
goto again;
}
......@@ -442,6 +439,8 @@ static int hpfs_rmdir(struct inode *dir, struct dentry *dentry)
int err;
int r;
dentry_unhash(dentry);
hpfs_adjust_length(name, &len);
hpfs_lock(dir->i_sb);
err = -ENOENT;
......@@ -535,6 +534,10 @@ static int hpfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct buffer_head *bh;
struct fnode *fnode;
int err;
if (new_inode && S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
if ((err = hpfs_chk_name(new_name, &new_len))) return err;
err = 0;
hpfs_adjust_length(old_name, &old_len);
......
......@@ -609,6 +609,8 @@ static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry)
int ret;
uint32_t now = get_seconds();
dentry_unhash(dentry);
for (fd = f->dents ; fd; fd = fd->next) {
if (fd->ino)
return -ENOTEMPTY;
......@@ -784,6 +786,9 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
uint8_t type;
uint32_t now;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
/* The VFS will check for us and prevent trying to rename a
* file over a directory and vice versa, but if it's a directory,
* the VFS can't check whether the victim is empty. The filesystem
......
......@@ -360,6 +360,8 @@ static int jfs_rmdir(struct inode *dip, struct dentry *dentry)
jfs_info("jfs_rmdir: dip:0x%p name:%s", dip, dentry->d_name.name);
dentry_unhash(dentry);
/* Init inode for quota operations. */
dquot_initialize(dip);
dquot_initialize(ip);
......@@ -1095,6 +1097,9 @@ static int jfs_rename(struct inode *old_dir, struct dentry *old_dentry,
jfs_info("jfs_rename: %s %s", old_dentry->d_name.name,
new_dentry->d_name.name);
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
dquot_initialize(old_dir);
dquot_initialize(new_dir);
......
......@@ -273,6 +273,8 @@ static int logfs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
dentry_unhash(dentry);
if (!logfs_empty_dir(inode))
return -ENOTEMPTY;
......@@ -622,6 +624,9 @@ static int logfs_rename_cross(struct inode *old_dir, struct dentry *old_dentry,
loff_t pos;
int err;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
/* 1. locate source dd */
err = logfs_get_dd(old_dir, old_dentry, &dd, &pos);
if (err)
......
......@@ -168,6 +168,8 @@ static int minix_rmdir(struct inode * dir, struct dentry *dentry)
struct inode * inode = dentry->d_inode;
int err = -ENOTEMPTY;
dentry_unhash(dentry);
if (minix_empty_dir(inode)) {
err = minix_unlink(dir, dentry);
if (!err) {
......@@ -190,6 +192,9 @@ static int minix_rename(struct inode * old_dir, struct dentry *old_dentry,
struct minix_dir_entry * old_de;
int err = -ENOENT;
if (new_inode && S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
old_de = minix_find_entry(old_dentry, &old_page);
if (!old_de)
goto out;
......
......@@ -391,79 +391,28 @@ void path_put(struct path *path)
}
EXPORT_SYMBOL(path_put);
/**
* nameidata_drop_rcu - drop this nameidata out of rcu-walk
* @nd: nameidata pathwalk data to drop
* Returns: 0 on success, -ECHILD on failure
*
/*
* Path walking has 2 modes, rcu-walk and ref-walk (see
* Documentation/filesystems/path-lookup.txt). __drop_rcu* functions attempt
* to drop out of rcu-walk mode and take normal reference counts on dentries
* and vfsmounts to transition to rcu-walk mode. __drop_rcu* functions take
* refcounts at the last known good point before rcu-walk got stuck, so
* ref-walk may continue from there. If this is not successful (eg. a seqcount
* has changed), then failure is returned and path walk restarts from the
* beginning in ref-walk mode.
*
* nameidata_drop_rcu attempts to drop the current nd->path and nd->root into
* ref-walk. Must be called from rcu-walk context.
* Documentation/filesystems/path-lookup.txt). In situations when we can't
* continue in RCU mode, we attempt to drop out of rcu-walk mode and grab
* normal reference counts on dentries and vfsmounts to transition to rcu-walk
* mode. Refcounts are grabbed at the last known good point before rcu-walk
* got stuck, so ref-walk may continue from there. If this is not successful
* (eg. a seqcount has changed), then failure is returned and it's up to caller
* to restart the path walk from the beginning in ref-walk mode.
*/
static int nameidata_drop_rcu(struct nameidata *nd)
{
struct fs_struct *fs = current->fs;
struct dentry *dentry = nd->path.dentry;
int want_root = 0;
BUG_ON(!(nd->flags & LOOKUP_RCU));
if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) {
want_root = 1;
spin_lock(&fs->lock);
if (nd->root.mnt != fs->root.mnt ||
nd->root.dentry != fs->root.dentry)
goto err_root;
}
spin_lock(&dentry->d_lock);
if (!__d_rcu_to_refcount(dentry, nd->seq))
goto err;
BUG_ON(nd->inode != dentry->d_inode);
spin_unlock(&dentry->d_lock);
if (want_root) {
path_get(&nd->root);
spin_unlock(&fs->lock);
}
mntget(nd->path.mnt);
rcu_read_unlock();
br_read_unlock(vfsmount_lock);
nd->flags &= ~LOOKUP_RCU;
return 0;
err:
spin_unlock(&dentry->d_lock);
err_root:
if (want_root)
spin_unlock(&fs->lock);
return -ECHILD;
}
/* Try to drop out of rcu-walk mode if we were in it, otherwise do nothing. */
static inline int nameidata_drop_rcu_maybe(struct nameidata *nd)
{
if (nd->flags & LOOKUP_RCU)
return nameidata_drop_rcu(nd);
return 0;
}
/**
* nameidata_dentry_drop_rcu - drop nameidata and dentry out of rcu-walk
* @nd: nameidata pathwalk data to drop
* @dentry: dentry to drop
* unlazy_walk - try to switch to ref-walk mode.
* @nd: nameidata pathwalk data
* @dentry: child of nd->path.dentry or NULL
* Returns: 0 on success, -ECHILD on failure
*
* nameidata_dentry_drop_rcu attempts to drop the current nd->path and nd->root,
* and dentry into ref-walk. @dentry must be a path found by a do_lookup call on
* @nd. Must be called from rcu-walk context.
* unlazy_walk attempts to legitimize the current nd->path, nd->root and dentry
* for ref-walk mode. @dentry must be a path found by a do_lookup call on
* @nd or NULL. Must be called from rcu-walk context.
*/
static int nameidata_dentry_drop_rcu(struct nameidata *nd, struct dentry *dentry)
static int unlazy_walk(struct nameidata *nd, struct dentry *dentry)
{
struct fs_struct *fs = current->fs;
struct dentry *parent = nd->path.dentry;
......@@ -478,18 +427,25 @@ static int nameidata_dentry_drop_rcu(struct nameidata *nd, struct dentry *dentry
goto err_root;
}
spin_lock(&parent->d_lock);
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
if (!__d_rcu_to_refcount(dentry, nd->seq))
goto err;
/*
* If the sequence check on the child dentry passed, then the child has
* not been removed from its parent. This means the parent dentry must
* be valid and able to take a reference at this point.
*/
BUG_ON(!IS_ROOT(dentry) && dentry->d_parent != parent);
BUG_ON(!parent->d_count);
parent->d_count++;
spin_unlock(&dentry->d_lock);
if (!dentry) {
if (!__d_rcu_to_refcount(parent, nd->seq))
goto err_parent;
BUG_ON(nd->inode != parent->d_inode);
} else {
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
if (!__d_rcu_to_refcount(dentry, nd->seq))
goto err_child;
/*
* If the sequence check on the child dentry passed, then
* the child has not been removed from its parent. This
* means the parent dentry must be valid and able to take
* a reference at this point.
*/
BUG_ON(!IS_ROOT(dentry) && dentry->d_parent != parent);
BUG_ON(!parent->d_count);
parent->d_count++;
spin_unlock(&dentry->d_lock);
}
spin_unlock(&parent->d_lock);
if (want_root) {
path_get(&nd->root);
......@@ -501,8 +457,10 @@ static int nameidata_dentry_drop_rcu(struct nameidata *nd, struct dentry *dentry
br_read_unlock(vfsmount_lock);
nd->flags &= ~LOOKUP_RCU;
return 0;
err:
err_child:
spin_unlock(&dentry->d_lock);
err_parent:
spin_unlock(&parent->d_lock);
err_root:
if (want_root)
......@@ -510,59 +468,6 @@ static int nameidata_dentry_drop_rcu(struct nameidata *nd, struct dentry *dentry
return -ECHILD;
}
/* Try to drop out of rcu-walk mode if we were in it, otherwise do nothing. */
static inline int nameidata_dentry_drop_rcu_maybe(struct nameidata *nd, struct dentry *dentry)
{
if (nd->flags & LOOKUP_RCU) {
if (unlikely(nameidata_dentry_drop_rcu(nd, dentry))) {
nd->flags &= ~LOOKUP_RCU;
if (!(nd->flags & LOOKUP_ROOT))
nd->root.mnt = NULL;
rcu_read_unlock();
br_read_unlock(vfsmount_lock);
return -ECHILD;
}
}
return 0;
}
/**
* nameidata_drop_rcu_last - drop nameidata ending path walk out of rcu-walk
* @nd: nameidata pathwalk data to drop
* Returns: 0 on success, -ECHILD on failure
*
* nameidata_drop_rcu_last attempts to drop the current nd->path into ref-walk.
* nd->path should be the final element of the lookup, so nd->root is discarded.
* Must be called from rcu-walk context.
*/
static int nameidata_drop_rcu_last(struct nameidata *nd)
{
struct dentry *dentry = nd->path.dentry;
BUG_ON(!(nd->flags & LOOKUP_RCU));
nd->flags &= ~LOOKUP_RCU;
if (!(nd->flags & LOOKUP_ROOT))
nd->root.mnt = NULL;
spin_lock(&dentry->d_lock);
if (!__d_rcu_to_refcount(dentry, nd->seq))
goto err_unlock;
BUG_ON(nd->inode != dentry->d_inode);
spin_unlock(&dentry->d_lock);
mntget(nd->path.mnt);
rcu_read_unlock();
br_read_unlock(vfsmount_lock);
return 0;
err_unlock:
spin_unlock(&dentry->d_lock);
rcu_read_unlock();
br_read_unlock(vfsmount_lock);
return -ECHILD;
}
/**
* release_open_intent - free up open intent resources
* @nd: pointer to nameidata
......@@ -606,26 +511,39 @@ do_revalidate(struct dentry *dentry, struct nameidata *nd)
return dentry;
}
/*
* handle_reval_path - force revalidation of a dentry
*
* In some situations the path walking code will trust dentries without
* revalidating them. This causes problems for filesystems that depend on
* d_revalidate to handle file opens (e.g. NFSv4). When FS_REVAL_DOT is set
* (which indicates that it's possible for the dentry to go stale), force
* a d_revalidate call before proceeding.
/**
* complete_walk - successful completion of path walk
* @nd: pointer nameidata
*
* Returns 0 if the revalidation was successful. If the revalidation fails,
* either return the error returned by d_revalidate or -ESTALE if the
* revalidation it just returned 0. If d_revalidate returns 0, we attempt to
* invalidate the dentry. It's up to the caller to handle putting references
* to the path if necessary.
* If we had been in RCU mode, drop out of it and legitimize nd->path.
* Revalidate the final result, unless we'd already done that during
* the path walk or the filesystem doesn't ask for it. Return 0 on
* success, -error on failure. In case of failure caller does not
* need to drop nd->path.
*/
static inline int handle_reval_path(struct nameidata *nd)
static int complete_walk(struct nameidata *nd)
{
struct dentry *dentry = nd->path.dentry;
int status;
if (nd->flags & LOOKUP_RCU) {
nd->flags &= ~LOOKUP_RCU;
if (!(nd->flags & LOOKUP_ROOT))
nd->root.mnt = NULL;
spin_lock(&dentry->d_lock);
if (unlikely(!__d_rcu_to_refcount(dentry, nd->seq))) {
spin_unlock(&dentry->d_lock);
rcu_read_unlock();
br_read_unlock(vfsmount_lock);
return -ECHILD;
}
BUG_ON(nd->inode != dentry->d_inode);
spin_unlock(&dentry->d_lock);
mntget(nd->path.mnt);
rcu_read_unlock();
br_read_unlock(vfsmount_lock);
}
if (likely(!(nd->flags & LOOKUP_JUMPED)))
return 0;
......@@ -643,6 +561,7 @@ static inline int handle_reval_path(struct nameidata *nd)
if (!status)
status = -ESTALE;
path_put(&nd->path);
return status;
}
......@@ -1241,13 +1160,8 @@ static int do_lookup(struct nameidata *nd, struct qstr *name,
if (likely(__follow_mount_rcu(nd, path, inode, false)))
return 0;
unlazy:
if (dentry) {
if (nameidata_dentry_drop_rcu(nd, dentry))
return -ECHILD;
} else {
if (nameidata_drop_rcu(nd))
return -ECHILD;
}
if (unlazy_walk(nd, dentry))
return -ECHILD;
} else {
dentry = __d_lookup(parent, name);
}
......@@ -1303,7 +1217,7 @@ static inline int may_lookup(struct nameidata *nd)
int err = exec_permission(nd->inode, IPERM_FLAG_RCU);
if (err != -ECHILD)
return err;
if (nameidata_drop_rcu(nd))
if (unlazy_walk(nd, NULL))
return -ECHILD;
}
return exec_permission(nd->inode, 0);
......@@ -1357,8 +1271,12 @@ static inline int walk_component(struct nameidata *nd, struct path *path,
return -ENOENT;
}
if (unlikely(inode->i_op->follow_link) && follow) {
if (nameidata_dentry_drop_rcu_maybe(nd, path->dentry))
return -ECHILD;
if (nd->flags & LOOKUP_RCU) {
if (unlikely(unlazy_walk(nd, path->dentry))) {
terminate_walk(nd);
return -ECHILD;
}
}
BUG_ON(inode != path->dentry->d_inode);
return 1;
}
......@@ -1657,18 +1575,8 @@ static int path_lookupat(int dfd, const char *name,
}
}
if (nd->flags & LOOKUP_RCU) {
/* went all way through without dropping RCU */
BUG_ON(err);
if (nameidata_drop_rcu_last(nd))
err = -ECHILD;
}
if (!err) {
err = handle_reval_path(nd);
if (err)
path_put(&nd->path);
}
if (!err)
err = complete_walk(nd);
if (!err && nd->flags & LOOKUP_DIRECTORY) {
if (!nd->inode->i_op->lookup) {
......@@ -2134,13 +2042,9 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
return ERR_PTR(error);
/* fallthrough */
case LAST_ROOT:
if (nd->flags & LOOKUP_RCU) {
if (nameidata_drop_rcu_last(nd))
return ERR_PTR(-ECHILD);
}
error = handle_reval_path(nd);
error = complete_walk(nd);
if (error)
goto exit;
return ERR_PTR(error);
audit_inode(pathname, nd->path.dentry);
if (open_flag & O_CREAT) {
error = -EISDIR;
......@@ -2148,10 +2052,9 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
}
goto ok;
case LAST_BIND:
/* can't be RCU mode here */
error = handle_reval_path(nd);
error = complete_walk(nd);
if (error)
goto exit;
return ERR_PTR(error);
audit_inode(pathname, dir);
goto ok;
}
......@@ -2170,10 +2073,9 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
if (error) /* symlink */
return NULL;
/* sayonara */
if (nd->flags & LOOKUP_RCU) {
if (nameidata_drop_rcu_last(nd))
return ERR_PTR(-ECHILD);
}
error = complete_walk(nd);
if (error)
return ERR_PTR(-ECHILD);
error = -ENOTDIR;
if (nd->flags & LOOKUP_DIRECTORY) {
......@@ -2185,11 +2087,9 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
}
/* create side of things */
if (nd->flags & LOOKUP_RCU) {
if (nameidata_drop_rcu_last(nd))
return ERR_PTR(-ECHILD);
}
error = complete_walk(nd);
if (error)
return ERR_PTR(error);
audit_inode(pathname, dir);
error = -EISDIR;
......@@ -2629,10 +2529,10 @@ SYSCALL_DEFINE2(mkdir, const char __user *, pathname, int, mode)
}
/*
* We try to drop the dentry early: we should have
* a usage count of 2 if we're the only user of this
* dentry, and if that is true (possibly after pruning
* the dcache), then we drop the dentry now.
* The dentry_unhash() helper will try to drop the dentry early: we
* should have a usage count of 2 if we're the only user of this
* dentry, and if that is true (possibly after pruning the dcache),
* then we drop the dentry now.
*
* A low-level filesystem can, if it choses, legally
* do a
......@@ -2645,10 +2545,9 @@ SYSCALL_DEFINE2(mkdir, const char __user *, pathname, int, mode)
*/
void dentry_unhash(struct dentry *dentry)
{
dget(dentry);
shrink_dcache_parent(dentry);
spin_lock(&dentry->d_lock);
if (dentry->d_count == 2)
if (dentry->d_count == 1)
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
}
......@@ -2664,25 +2563,26 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry)
return -EPERM;
mutex_lock(&dentry->d_inode->i_mutex);
dentry_unhash(dentry);
error = -EBUSY;
if (d_mountpoint(dentry))
error = -EBUSY;
else {
error = security_inode_rmdir(dir, dentry);
if (!error) {
error = dir->i_op->rmdir(dir, dentry);
if (!error) {
dentry->d_inode->i_flags |= S_DEAD;
dont_mount(dentry);
}
}
}
goto out;
error = security_inode_rmdir(dir, dentry);
if (error)
goto out;
error = dir->i_op->rmdir(dir, dentry);
if (error)
goto out;
dentry->d_inode->i_flags |= S_DEAD;
dont_mount(dentry);
out:
mutex_unlock(&dentry->d_inode->i_mutex);
if (!error) {
if (!error)
d_delete(dentry);
}
dput(dentry);
return error;
}
......@@ -3053,12 +2953,7 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
* 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.
* d) some filesystems don't support opened-but-unlinked directories,
* either because of layout or because they are not ready to deal with
* all cases correctly. The latter will be fixed (taking this sort of
* stuff into VFS), but the former is not going away. Solution: the same
* trick as in rmdir().
* e) conversion from fhandle to dentry may come in the wrong moment - when
* d) conversion from fhandle to dentry may come in the wrong moment - when
* we are removing the target. Solution: we will have to grab ->i_mutex
* in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on
* ->i_mutex on parents, which works but leads to some truly excessive
......@@ -3068,7 +2963,7 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
int error = 0;
struct inode *target;
struct inode *target = new_dentry->d_inode;
/*
* If we are going to change the parent - check write permissions,
......@@ -3084,26 +2979,24 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
if (error)
return error;
target = new_dentry->d_inode;
if (target)
mutex_lock(&target->i_mutex);
if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
error = -EBUSY;
else {
if (target)
dentry_unhash(new_dentry);
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
}
error = -EBUSY;
if (d_mountpoint(old_dentry) || d_mountpoint(new_dentry))
goto out;
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
if (error)
goto out;
if (target) {
if (!error) {
target->i_flags |= S_DEAD;
dont_mount(new_dentry);
}
mutex_unlock(&target->i_mutex);
if (d_unhashed(new_dentry))
d_rehash(new_dentry);
dput(new_dentry);
target->i_flags |= S_DEAD;
dont_mount(new_dentry);
}
out:
if (target)
mutex_unlock(&target->i_mutex);
if (!error)
if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
d_move(old_dentry,new_dentry);
......@@ -3113,7 +3006,7 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct inode *target;
struct inode *target = new_dentry->d_inode;
int error;
error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry);
......@@ -3121,19 +3014,22 @@ static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
return error;
dget(new_dentry);
target = new_dentry->d_inode;
if (target)
mutex_lock(&target->i_mutex);
error = -EBUSY;
if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
error = -EBUSY;
else
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
if (!error) {
if (target)
dont_mount(new_dentry);
if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
d_move(old_dentry, new_dentry);
}
goto out;
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
if (error)
goto out;
if (target)
dont_mount(new_dentry);
if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
d_move(old_dentry, new_dentry);
out:
if (target)
mutex_unlock(&target->i_mutex);
dput(new_dentry);
......
......@@ -1695,7 +1695,7 @@ static int graft_tree(struct vfsmount *mnt, struct path *path)
static int flags_to_propagation_type(int flags)
{
int type = flags & ~MS_REC;
int type = flags & ~(MS_REC | MS_SILENT);
/* Fail if any non-propagation flags are set */
if (type & ~(MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE))
......
......@@ -1033,6 +1033,8 @@ static int ncp_rmdir(struct inode *dir, struct dentry *dentry)
DPRINTK("ncp_rmdir: removing %s/%s\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
dentry_unhash(dentry);
error = -EBUSY;
if (!d_unhashed(dentry))
goto out;
......@@ -1139,6 +1141,9 @@ static int ncp_rename(struct inode *old_dir, struct dentry *old_dentry,
old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
new_dentry->d_parent->d_name.name, new_dentry->d_name.name);
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
ncp_age_dentry(server, old_dentry);
ncp_age_dentry(server, new_dentry);
......
......@@ -334,6 +334,8 @@ static int nilfs_rmdir(struct inode *dir, struct dentry *dentry)
struct nilfs_transaction_info ti;
int err;
dentry_unhash(dentry);
err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
if (err)
return err;
......@@ -369,6 +371,9 @@ static int nilfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct nilfs_transaction_info ti;
int err;
if (new_inode && S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
err = nilfs_transaction_begin(old_dir->i_sb, &ti, 1);
if (unlikely(err))
return err;
......
......@@ -240,8 +240,12 @@ static int omfs_remove(struct inode *dir, struct dentry *dentry)
struct inode *inode = dentry->d_inode;
int ret;
if (S_ISDIR(inode->i_mode) && !omfs_dir_is_empty(inode))
return -ENOTEMPTY;
if (S_ISDIR(inode->i_mode)) {
dentry_unhash(dentry);
if (!omfs_dir_is_empty(inode))
return -ENOTEMPTY;
}
ret = omfs_delete_entry(dentry);
if (ret)
......@@ -378,6 +382,9 @@ static int omfs_rename(struct inode *old_dir, struct dentry *old_dentry,
int err;
if (new_inode) {
if (S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
/* overwriting existing file/dir */
err = omfs_remove(new_dir, new_dentry);
if (err)
......
......@@ -831,6 +831,8 @@ static int reiserfs_rmdir(struct inode *dir, struct dentry *dentry)
INITIALIZE_PATH(path);
struct reiserfs_dir_entry de;
dentry_unhash(dentry);
/* we will be doing 2 balancings and update 2 stat data, we change quotas
* of the owner of the directory and of the owner of the parent directory.
* The quota structure is possibly deleted only on last iput => outside
......@@ -1225,6 +1227,9 @@ static int reiserfs_rename(struct inode *old_dir, struct dentry *old_dentry,
unsigned long savelink = 1;
struct timespec ctime;
if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
dentry_unhash(new_dentry);
/* three balancings: (1) old name removal, (2) new name insertion
and (3) maybe "save" link insertion
stat data updates: (1) old directory,
......
......@@ -105,7 +105,6 @@ static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
mutex_unlock(&dentry->d_inode->i_mutex);
if (!error)
d_delete(dentry);
dput(dentry);
return error;
}
......
......@@ -196,6 +196,8 @@ static int sysv_rmdir(struct inode * dir, struct dentry * dentry)
struct inode *inode = dentry->d_inode;
int err = -ENOTEMPTY;
dentry_unhash(dentry);
if (sysv_empty_dir(inode)) {
err = sysv_unlink(dir, dentry);
if (!err) {
......@@ -222,6 +224,9 @@ static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
struct sysv_dir_entry * old_de;
int err = -ENOENT;
if (new_inode && S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
old_de = sysv_find_entry(old_dentry, &old_page);
if (!old_de)
goto out;
......
......@@ -656,6 +656,8 @@ static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
struct ubifs_inode *dir_ui = ubifs_inode(dir);
struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
dentry_unhash(dentry);
/*
* Budget request settings: deletion direntry, deletion inode and
* changing the parent inode. If budgeting fails, go ahead anyway
......@@ -976,6 +978,9 @@ static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
.dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
struct timespec time;
if (new_inode && S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
/*
* Budget request settings: deletion direntry, new direntry, removing
* the old inode, and changing old and new parent directory inodes.
......
......@@ -783,6 +783,8 @@ static int udf_rmdir(struct inode *dir, struct dentry *dentry)
struct fileIdentDesc *fi, cfi;
struct kernel_lb_addr tloc;
dentry_unhash(dentry);
retval = -ENOENT;
fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
if (!fi)
......@@ -1081,6 +1083,9 @@ static int udf_rename(struct inode *old_dir, struct dentry *old_dentry,
struct kernel_lb_addr tloc;
struct udf_inode_info *old_iinfo = UDF_I(old_inode);
if (new_inode && S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
if (ofi) {
if (ofibh.sbh != ofibh.ebh)
......
......@@ -258,6 +258,8 @@ static int ufs_rmdir (struct inode * dir, struct dentry *dentry)
struct inode * inode = dentry->d_inode;
int err= -ENOTEMPTY;
dentry_unhash(dentry);
lock_ufs(dir->i_sb);
if (ufs_empty_dir (inode)) {
err = ufs_unlink(dir, dentry);
......@@ -282,6 +284,9 @@ static int ufs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct ufs_dir_entry *old_de;
int err = -ENOENT;
if (new_inode && S_ISDIR(new_inode->i_mode))
dentry_unhash(new_dentry);
old_de = ufs_find_entry(old_dir, &old_dentry->d_name, &old_page);
if (!old_de)
goto out;
......
......@@ -217,8 +217,24 @@ int cont_write_begin(struct file *, struct address_space *, loff_t,
get_block_t *, loff_t *);
int generic_cont_expand_simple(struct inode *inode, loff_t size);
int block_commit_write(struct page *page, unsigned from, unsigned to);
int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
get_block_t get_block);
int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
get_block_t get_block);
/* Convert errno to return value from ->page_mkwrite() call */
static inline int block_page_mkwrite_return(int err)
{
if (err == 0)
return VM_FAULT_LOCKED;
if (err == -EFAULT)
return VM_FAULT_NOPAGE;
if (err == -ENOMEM)
return VM_FAULT_OOM;
if (err == -EAGAIN)
return VM_FAULT_RETRY;
/* -ENOSPC, -EDQUOT, -EIO ... */
return VM_FAULT_SIGBUS;
}
sector_t generic_block_bmap(struct address_space *, sector_t, get_block_t *);
int block_truncate_page(struct address_space *, loff_t, get_block_t *);
int nobh_write_begin(struct address_space *, loff_t, unsigned, unsigned,
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册