.llseek = default_llseek,
};
+static struct dentry *
+canonical_dentry(struct inode *ip)
+{
+ struct vcache *vcp = VTOAFS(ip);
+ struct dentry *first = NULL, *ret = NULL, *cur;
+#if defined(D_ALIAS_IS_HLIST)
+ struct hlist_node *p;
+#endif
+
+ /* general strategy:
+ * if vcp->target_link is set, and can be found in ip->i_dentry, use that.
+ * otherwise, use the first dentry in ip->i_dentry.
+ * if ip->i_dentry is empty, use the 'dentry' argument we were given.
+ */
+ /* note that vcp->target_link specifies which dentry to use, but we have
+ * no reference held on that dentry. so, we cannot use or dereference
+ * vcp->target_link itself, since it may have been freed. instead, we only
+ * use it to compare to pointers in the ip->i_dentry list. */
+
+ d_prune_aliases(ip);
+
+# ifdef HAVE_DCACHE_LOCK
+ spin_lock(&dcache_lock);
+# else
+ spin_lock(&ip->i_lock);
+# endif
+
+#if defined(D_ALIAS_IS_HLIST)
+ hlist_for_each_entry(cur, p, &ip->i_dentry, d_alias) {
+#else
+ list_for_each_entry_reverse(cur, &ip->i_dentry, d_alias) {
+#endif
+
+ if (!vcp->target_link || cur == vcp->target_link) {
+ ret = cur;
+ break;
+ }
+
+ if (!first) {
+ first = cur;
+ }
+ }
+ if (!ret && first) {
+ ret = first;
+ }
+
+ vcp->target_link = ret;
+
+# ifdef HAVE_DCACHE_LOCK
+ if (ret) {
+ dget_locked(ret);
+ }
+ spin_unlock(&dcache_lock);
+# else
+ if (ret) {
+ dget(ret);
+ }
+ spin_unlock(&ip->i_lock);
+# endif
+
+ return ret;
+}
/**********************************************************************
* AFS Linux dentry operations
}
AFS_GUNLOCK();
crfree(credp);
- return -code;
+ return afs_convert_code(code);
}
static int
return 0;
}
+#ifdef STRUCT_DENTRY_OPERATIONS_HAS_D_AUTOMOUNT
+static struct vfsmount *
+afs_dentry_automount(struct path *path)
+{
+ struct dentry *target;
+
+ target = canonical_dentry(path->dentry->d_inode);
+
+ if (target == path->dentry) {
+ dput(target);
+ target = NULL;
+ }
+
+ if (target) {
+ dput(path->dentry);
+ path->dentry = target;
+
+ } else {
+ spin_lock(&path->dentry->d_lock);
+ path->dentry->d_flags &= ~DCACHE_NEED_AUTOMOUNT;
+ spin_unlock(&path->dentry->d_lock);
+ }
+
+ return NULL;
+}
+#endif /* STRUCT_DENTRY_OPERATIONS_HAS_D_AUTOMOUNT */
+
struct dentry_operations afs_dentry_operations = {
.d_revalidate = afs_linux_dentry_revalidate,
.d_delete = afs_dentry_delete,
.d_iput = afs_dentry_iput,
+#ifdef STRUCT_DENTRY_OPERATIONS_HAS_D_AUTOMOUNT
+ .d_automount = afs_dentry_automount,
+#endif /* STRUCT_DENTRY_OPERATIONS_HAS_D_AUTOMOUNT */
};
/**********************************************************************
* name is in kernel space at this point.
*/
static int
-#if defined(IOP_MKDIR_TAKES_UMODE_T)
+#if defined(IOP_CREATE_TAKES_UMODE_T)
afs_linux_create(struct inode *dip, struct dentry *dp, umode_t mode,
struct nameidata *nd)
#else
if (vcp) {
struct vattr vattr;
+ struct vcache *parent_vc = VTOAFS(dip);
+
+ if (parent_vc == vcp) {
+ /* This is possible if the parent dir is a mountpoint to a volume,
+ * and the dir entry we looked up is a mountpoint to the same
+ * volume. Linux cannot cope with this, so return an error instead
+ * of risking a deadlock or panic. */
+ afs_PutVCache(vcp);
+ code = EDEADLK;
+ AFS_GUNLOCK();
+ goto done;
+ }
ip = AFSTOV(vcp);
afs_getattr(vcp, &vattr, credp);
AFS_GUNLOCK();
if (ip && S_ISDIR(ip->i_mode)) {
+ int retry = 1;
struct dentry *alias;
- /* Try to invalidate an existing alias in favor of our new one */
- alias = d_find_alias(ip);
- /* But not if it's disconnected; then we want d_splice_alias below */
- if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) {
- if (d_invalidate(alias) == 0) {
- dput(alias);
- } else {
- iput(ip);
- crfree(credp);
- return alias;
+ while (retry) {
+ retry = 0;
+
+ /* Try to invalidate an existing alias in favor of our new one */
+ alias = d_find_alias(ip);
+ /* But not if it's disconnected; then we want d_splice_alias below */
+ if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) {
+ if (d_invalidate(alias) == 0) {
+ /* there may be more aliases; try again until we run out */
+ retry = 1;
+ }
}
+
+ dput(alias);
}
+
+#ifdef STRUCT_DENTRY_OPERATIONS_HAS_D_AUTOMOUNT
+ ip->i_flags |= S_AUTOMOUNT;
+#endif
}
newdp = d_splice_alias(ip, dp);
+ done:
crfree(credp);
/* It's ok for the file to not be found. That's noted by the caller by
}
#endif
+#ifndef STRUCT_DENTRY_OPERATIONS_HAS_D_AUTOMOUNT
+static void *
+afs_linux_dir_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ struct dentry **dpp;
+ struct dentry *target;
+
+ target = canonical_dentry(dentry->d_inode);
+
+# ifdef STRUCT_NAMEIDATA_HAS_PATH
+ dpp = &nd->path.dentry;
+# else
+ dpp = &nd->dentry;
+# endif
+
+ dput(*dpp);
+
+ if (target) {
+ *dpp = target;
+ } else {
+ *dpp = dget(dentry);
+ }
+
+ return NULL;
+}
+#endif /* !STRUCT_DENTRY_OPERATIONS_HAS_D_AUTOMOUNT */
+
static struct inode_operations afs_file_iops = {
.permission = afs_linux_permission,
.rename = afs_linux_rename,
.getattr = afs_linux_getattr,
.permission = afs_linux_permission,
+#ifndef STRUCT_DENTRY_OPERATIONS_HAS_D_AUTOMOUNT
+ .follow_link = afs_linux_dir_follow_link,
+#endif
};
/* We really need a separate symlink set of ops, since do_follow_link()
git://git.openafs.org / openafs.git / blobdiff