Fix 'zfs rollback' on mounted file systems

[zfs.git] / module / zfs / zpl_inode.c

diff --git a/module/zfs/zpl_inode.c b/module/zfs/zpl_inode.c
index 6175c2e..15ee0f6 100644 (file)
--- a/module/zfs/zpl_inode.c
+++ b/module/zfs/zpl_inode.c
@@ -46,6 +46,10 @@ zpl_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
        ASSERT3S(error, <=, 0);
        crfree(cr);
 
+       spin_lock(&dentry->d_lock);
+       dentry->d_time = jiffies;
+       spin_unlock(&dentry->d_lock);
+
        if (error) {
                if (error == -ENOENT)
                        return d_splice_alias(NULL, dentry);
@@ -57,12 +61,10 @@ zpl_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 }
 
 void
-zpl_vap_init(vattr_t *vap, struct inode *dir, struct dentry *dentry,
-    zpl_umode_t mode, cred_t *cr)
+zpl_vap_init(vattr_t *vap, struct inode *dir, zpl_umode_t mode, cred_t *cr)
 {
        vap->va_mask = ATTR_MODE;
        vap->va_mode = mode;
-       vap->va_dentry = dentry;
        vap->va_uid = crgetfsuid(cr);
 
        if (dir && dir->i_mode & S_ISGID) {
@@ -90,12 +92,14 @@ zpl_create(struct inode *dir, struct dentry *dentry, zpl_umode_t mode,
 
        crhold(cr);
        vap = kmem_zalloc(sizeof(vattr_t), KM_SLEEP);
-       zpl_vap_init(vap, dir, dentry, mode, cr);
+       zpl_vap_init(vap, dir, mode, cr);
 
        error = -zfs_create(dir, dname(dentry), vap, 0, mode, &ip, cr, 0, NULL);
        if (error == 0) {
                error = zpl_xattr_security_init(ip, dir, &dentry->d_name);
                VERIFY3S(error, ==, 0);
+               d_instantiate(dentry, ip);
+               d_set_d_op(dentry, &zpl_dentry_operations);
        }
 
        kmem_free(vap, sizeof(vattr_t));
@@ -123,11 +127,15 @@ zpl_mknod(struct inode *dir, struct dentry *dentry, zpl_umode_t mode,
 
        crhold(cr);
        vap = kmem_zalloc(sizeof(vattr_t), KM_SLEEP);
-       zpl_vap_init(vap, dir, dentry, mode, cr);
+       zpl_vap_init(vap, dir, mode, cr);
        vap->va_rdev = rdev;
 
-       error = -zfs_create(dir, (char *)dentry->d_name.name,
-           vap, 0, mode, &ip, cr, 0, NULL);
+       error = -zfs_create(dir, dname(dentry), vap, 0, mode, &ip, cr, 0, NULL);
+       if (error == 0) {
+               d_instantiate(dentry, ip);
+               d_set_d_op(dentry, &zpl_dentry_operations);
+       }
+
        kmem_free(vap, sizeof(vattr_t));
        crfree(cr);
        ASSERT3S(error, <=, 0);
@@ -159,9 +167,14 @@ zpl_mkdir(struct inode *dir, struct dentry *dentry, zpl_umode_t mode)
 
        crhold(cr);
        vap = kmem_zalloc(sizeof(vattr_t), KM_SLEEP);
-       zpl_vap_init(vap, dir, dentry, mode | S_IFDIR, cr);
+       zpl_vap_init(vap, dir, mode | S_IFDIR, cr);
 
        error = -zfs_mkdir(dir, dname(dentry), vap, &ip, cr, 0, NULL);
+       if (error == 0) {
+               d_instantiate(dentry, ip);
+               d_set_d_op(dentry, &zpl_dentry_operations);
+       }
+
        kmem_free(vap, sizeof(vattr_t));
        crfree(cr);
        ASSERT3S(error, <=, 0);
@@ -262,9 +275,14 @@ zpl_symlink(struct inode *dir, struct dentry *dentry, const char *name)
 
        crhold(cr);
        vap = kmem_zalloc(sizeof(vattr_t), KM_SLEEP);
-       zpl_vap_init(vap, dir, dentry, S_IFLNK | S_IRWXUGO, cr);
+       zpl_vap_init(vap, dir, S_IFLNK | S_IRWXUGO, cr);
 
        error = -zfs_symlink(dir, dname(dentry), vap, (char *)name, &ip, cr, 0);
+       if (error == 0) {
+               d_instantiate(dentry, ip);
+               d_set_d_op(dentry, &zpl_dentry_operations);
+       }
+
        kmem_free(vap, sizeof(vattr_t));
        crfree(cr);
        ASSERT3S(error, <=, 0);
@@ -334,6 +352,7 @@ zpl_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
        }
 
        d_instantiate(dentry, ip);
+       d_set_d_op(dentry, &zpl_dentry_operations);
 out:
        crfree(cr);
        ASSERT3S(error, <=, 0);
@@ -378,6 +397,44 @@ zpl_fallocate(struct inode *ip, int mode, loff_t offset, loff_t len)
 }
 #endif /* HAVE_INODE_FALLOCATE */
 
+static int
+#ifdef HAVE_D_REVALIDATE_NAMEIDATA
+zpl_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+       unsigned int flags = nd->flags;
+#else
+zpl_revalidate(struct dentry *dentry, unsigned int flags)
+{
+#endif /* HAVE_D_REVALIDATE_NAMEIDATA */
+       zfs_sb_t *zsb = dentry->d_sb->s_fs_info;
+       int error;
+
+       if (flags & LOOKUP_RCU)
+               return (-ECHILD);
+
+       /*
+        * After a rollback negative dentries created before the rollback
+        * time must be invalidated.  Otherwise they can obscure files which
+        * are only present in the rolled back dataset.
+        */
+       if (dentry->d_inode == NULL) {
+               spin_lock(&dentry->d_lock);
+               error = time_before(dentry->d_time, zsb->z_rollback_time);
+               spin_unlock(&dentry->d_lock);
+
+               if (error)
+                       return (0);
+       }
+
+       /*
+        * The dentry may reference a stale inode if a mounted file system
+        * was rolled back to a point in time where the object didn't exist.
+        */
+       if (dentry->d_inode && ITOZ(dentry->d_inode)->z_is_stale)
+               return (0);
+
+       return (1);
+}
 
 const struct inode_operations zpl_inode_operations = {
        .create         = zpl_create,
@@ -440,3 +497,7 @@ const struct inode_operations zpl_special_inode_operations = {
        .removexattr    = generic_removexattr,
        .listxattr      = zpl_xattr_list,
 };
+
+dentry_operations_t zpl_dentry_operations = {
+       .d_revalidate   = zpl_revalidate,
+};