diff options
Diffstat (limited to 'fs/gfs2/ops_dentry.c')
-rw-r--r-- | fs/gfs2/ops_dentry.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/fs/gfs2/ops_dentry.c b/fs/gfs2/ops_dentry.c new file mode 100644 index 00000000000..5c618611c11 --- /dev/null +++ b/fs/gfs2/ops_dentry.c @@ -0,0 +1,117 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License v.2. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/completion.h> +#include <linux/buffer_head.h> +#include <linux/smp_lock.h> +#include <asm/semaphore.h> + +#include "gfs2.h" +#include "dir.h" +#include "glock.h" +#include "ops_dentry.h" + +/** + * gfs2_drevalidate - Check directory lookup consistency + * @dentry: the mapping to check + * @nd: + * + * Check to make sure the lookup necessary to arrive at this inode from its + * parent is still good. + * + * Returns: 1 if the dentry is ok, 0 if it isn't + */ + +static int gfs2_drevalidate(struct dentry *dentry, struct nameidata *nd) +{ + struct dentry *parent = dget_parent(dentry); + struct gfs2_inode *dip = get_v2ip(parent->d_inode); + struct gfs2_sbd *sdp = dip->i_sbd; + struct inode *inode; + struct gfs2_holder d_gh; + struct gfs2_inode *ip; + struct gfs2_inum inum; + unsigned int type; + int error; + + lock_kernel(); + + atomic_inc(&sdp->sd_ops_dentry); + + inode = dentry->d_inode; + if (inode && is_bad_inode(inode)) + goto invalid; + + error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh); + if (error) + goto fail; + + error = gfs2_dir_search(dip, &dentry->d_name, &inum, &type); + switch (error) { + case 0: + if (!inode) + goto invalid_gunlock; + break; + case -ENOENT: + if (!inode) + goto valid_gunlock; + goto invalid_gunlock; + default: + goto fail_gunlock; + } + + ip = get_v2ip(inode); + + if (!gfs2_inum_equal(&ip->i_num, &inum)) + goto invalid_gunlock; + + if (IF2DT(ip->i_di.di_mode) != type) { + gfs2_consist_inode(dip); + goto fail_gunlock; + } + + valid_gunlock: + gfs2_glock_dq_uninit(&d_gh); + + valid: + unlock_kernel(); + dput(parent); + return 1; + + invalid_gunlock: + gfs2_glock_dq_uninit(&d_gh); + + invalid: + if (inode && S_ISDIR(inode->i_mode)) { + if (have_submounts(dentry)) + goto valid; + shrink_dcache_parent(dentry); + } + d_drop(dentry); + + unlock_kernel(); + dput(parent); + return 0; + + fail_gunlock: + gfs2_glock_dq_uninit(&d_gh); + + fail: + unlock_kernel(); + dput(parent); + return 0; +} + +struct dentry_operations gfs2_dops = { + .d_revalidate = gfs2_drevalidate, +}; + |