diff options
Diffstat (limited to 'kernel/fs/gfs2/dentry.c')
-rw-r--r-- | kernel/fs/gfs2/dentry.c | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/kernel/fs/gfs2/dentry.c b/kernel/fs/gfs2/dentry.c new file mode 100644 index 000000000..30822b148 --- /dev/null +++ b/kernel/fs/gfs2/dentry.c @@ -0,0 +1,134 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2006 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 version 2. + */ + +#include <linux/spinlock.h> +#include <linux/completion.h> +#include <linux/buffer_head.h> +#include <linux/gfs2_ondisk.h> +#include <linux/namei.h> +#include <linux/crc32.h> + +#include "gfs2.h" +#include "incore.h" +#include "dir.h" +#include "glock.h" +#include "super.h" +#include "util.h" +#include "inode.h" + +/** + * gfs2_drevalidate - Check directory lookup consistency + * @dentry: the mapping to check + * @flags: lookup flags + * + * 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, unsigned int flags) +{ + struct dentry *parent; + struct gfs2_sbd *sdp; + struct gfs2_inode *dip; + struct inode *inode; + struct gfs2_holder d_gh; + struct gfs2_inode *ip = NULL; + int error; + int had_lock = 0; + + if (flags & LOOKUP_RCU) + return -ECHILD; + + parent = dget_parent(dentry); + sdp = GFS2_SB(d_inode(parent)); + dip = GFS2_I(d_inode(parent)); + inode = d_inode(dentry); + + if (inode) { + if (is_bad_inode(inode)) + goto invalid; + ip = GFS2_I(inode); + } + + if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL) + goto valid; + + had_lock = (gfs2_glock_is_locked_by_me(dip->i_gl) != NULL); + if (!had_lock) { + error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh); + if (error) + goto fail; + } + + error = gfs2_dir_check(d_inode(parent), &dentry->d_name, ip); + switch (error) { + case 0: + if (!inode) + goto invalid_gunlock; + break; + case -ENOENT: + if (!inode) + goto valid_gunlock; + goto invalid_gunlock; + default: + goto fail_gunlock; + } + +valid_gunlock: + if (!had_lock) + gfs2_glock_dq_uninit(&d_gh); +valid: + dput(parent); + return 1; + +invalid_gunlock: + if (!had_lock) + gfs2_glock_dq_uninit(&d_gh); +invalid: + dput(parent); + return 0; + +fail_gunlock: + gfs2_glock_dq_uninit(&d_gh); +fail: + dput(parent); + return 0; +} + +static int gfs2_dhash(const struct dentry *dentry, struct qstr *str) +{ + str->hash = gfs2_disk_hash(str->name, str->len); + return 0; +} + +static int gfs2_dentry_delete(const struct dentry *dentry) +{ + struct gfs2_inode *ginode; + + if (d_really_is_negative(dentry)) + return 0; + + ginode = GFS2_I(d_inode(dentry)); + if (!ginode->i_iopen_gh.gh_gl) + return 0; + + if (test_bit(GLF_DEMOTE, &ginode->i_iopen_gh.gh_gl->gl_flags)) + return 1; + + return 0; +} + +const struct dentry_operations gfs2_dops = { + .d_revalidate = gfs2_drevalidate, + .d_hash = gfs2_dhash, + .d_delete = gfs2_dentry_delete, +}; + |