*/
static void prune_dcache(int count)
{
- struct super_block *sb, *n;
+ struct super_block *sb, *p = NULL;
int w_count;
int unused = dentry_stat.nr_unused;
int prune_ratio;
else
prune_ratio = unused / count;
spin_lock(&sb_lock);
- list_for_each_entry_safe(sb, n, &super_blocks, s_list) {
+ list_for_each_entry(sb, &super_blocks, s_list) {
if (list_empty(&sb->s_instances))
continue;
if (sb->s_nr_dentry_unused == 0)
up_read(&sb->s_umount);
}
spin_lock(&sb_lock);
- /* lock was dropped, must reset next */
- list_safe_reset_next(sb, n, s_list);
+ if (p)
+ __put_super(p);
count -= pruned;
- __put_super(sb);
+ p = sb;
/* more work left to do? */
if (count <= 0)
break;
}
+ if (p)
+ __put_super(p);
spin_unlock(&sb_lock);
spin_unlock(&dcache_lock);
}
}
/**
- * __d_path - return the path of a dentry
+ * Prepend path string to a buffer
+ *
* @path: the dentry/vfsmount to report
* @root: root vfsmnt/dentry (may be modified by this function)
- * @buffer: buffer to return value in
- * @buflen: buffer length
- *
- * Convert a dentry into an ASCII path name. If the entry has been deleted
- * the string " (deleted)" is appended. Note that this is ambiguous.
- *
- * Returns a pointer into the buffer or an error code if the
- * path was too long.
+ * @buffer: pointer to the end of the buffer
+ * @buflen: pointer to buffer length
*
- * "buflen" should be positive. Caller holds the dcache_lock.
+ * Caller holds the dcache_lock.
*
* If path is not reachable from the supplied root, then the value of
* root is changed (without modifying refcounts).
*/
-char *__d_path(const struct path *path, struct path *root,
- char *buffer, int buflen)
+static int prepend_path(const struct path *path, struct path *root,
+ char **buffer, int *buflen)
{
struct dentry *dentry = path->dentry;
struct vfsmount *vfsmnt = path->mnt;
- char *end = buffer + buflen;
- char *retval;
+ bool slash = false;
+ int error = 0;
spin_lock(&vfsmount_lock);
- prepend(&end, &buflen, "\0", 1);
- if (d_unlinked(dentry) &&
- (prepend(&end, &buflen, " (deleted)", 10) != 0))
- goto Elong;
-
- if (buflen < 1)
- goto Elong;
- /* Get '/' right */
- retval = end-1;
- *retval = '/';
-
- for (;;) {
+ while (dentry != root->dentry || vfsmnt != root->mnt) {
struct dentry * parent;
- if (dentry == root->dentry && vfsmnt == root->mnt)
- break;
if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) {
/* Global root? */
if (vfsmnt->mnt_parent == vfsmnt) {
}
parent = dentry->d_parent;
prefetch(parent);
- if ((prepend_name(&end, &buflen, &dentry->d_name) != 0) ||
- (prepend(&end, &buflen, "/", 1) != 0))
- goto Elong;
- retval = end;
+ error = prepend_name(buffer, buflen, &dentry->d_name);
+ if (!error)
+ error = prepend(buffer, buflen, "/", 1);
+ if (error)
+ break;
+
+ slash = true;
dentry = parent;
}
out:
+ if (!error && !slash)
+ error = prepend(buffer, buflen, "/", 1);
+
spin_unlock(&vfsmount_lock);
- return retval;
+ return error;
global_root:
- retval += 1; /* hit the slash */
- if (prepend_name(&retval, &buflen, &dentry->d_name) != 0)
- goto Elong;
+ /*
+ * Filesystems needing to implement special "root names"
+ * should do so with ->d_dname()
+ */
+ if (IS_ROOT(dentry) &&
+ (dentry->d_name.len != 1 || dentry->d_name.name[0] != '/')) {
+ WARN(1, "Root dentry has weird name <%.*s>\n",
+ (int) dentry->d_name.len, dentry->d_name.name);
+ }
root->mnt = vfsmnt;
root->dentry = dentry;
goto out;
+}
-Elong:
- retval = ERR_PTR(-ENAMETOOLONG);
- goto out;
+/**
+ * __d_path - return the path of a dentry
+ * @path: the dentry/vfsmount to report
+ * @root: root vfsmnt/dentry (may be modified by this function)
+ * @buf: buffer to return value in
+ * @buflen: buffer length
+ *
+ * Convert a dentry into an ASCII path name.
+ *
+ * Returns a pointer into the buffer or an error code if the
+ * path was too long.
+ *
+ * "buflen" should be positive. Caller holds the dcache_lock.
+ *
+ * If path is not reachable from the supplied root, then the value of
+ * root is changed (without modifying refcounts).
+ */
+char *__d_path(const struct path *path, struct path *root,
+ char *buf, int buflen)
+{
+ char *res = buf + buflen;
+ int error;
+
+ prepend(&res, &buflen, "\0", 1);
+ error = prepend_path(path, root, &res, &buflen);
+ if (error)
+ return ERR_PTR(error);
+
+ return res;
+}
+
+/*
+ * same as __d_path but appends "(deleted)" for unlinked files.
+ */
+static int path_with_deleted(const struct path *path, struct path *root,
+ char **buf, int *buflen)
+{
+ prepend(buf, buflen, "\0", 1);
+ if (d_unlinked(path->dentry)) {
+ int error = prepend(buf, buflen, " (deleted)", 10);
+ if (error)
+ return error;
+ }
+
+ return prepend_path(path, root, buf, buflen);
+}
+
+static int prepend_unreachable(char **buffer, int *buflen)
+{
+ return prepend(buffer, buflen, "(unreachable)", 13);
}
/**
*/
char *d_path(const struct path *path, char *buf, int buflen)
{
- char *res;
+ char *res = buf + buflen;
struct path root;
struct path tmp;
+ int error;
/*
* We have various synthetic filesystems that never get mounted. On
if (path->dentry->d_op && path->dentry->d_op->d_dname)
return path->dentry->d_op->d_dname(path->dentry, buf, buflen);
- read_lock(¤t->fs->lock);
- root = current->fs->root;
- path_get(&root);
- read_unlock(¤t->fs->lock);
+ get_fs_root(current->fs, &root);
spin_lock(&dcache_lock);
tmp = root;
- res = __d_path(path, &tmp, buf, buflen);
+ error = path_with_deleted(path, &tmp, &res, &buflen);
+ if (error)
+ res = ERR_PTR(error);
spin_unlock(&dcache_lock);
path_put(&root);
return res;
}
EXPORT_SYMBOL(d_path);
+/**
+ * d_path_with_unreachable - return the path of a dentry
+ * @path: path to report
+ * @buf: buffer to return value in
+ * @buflen: buffer length
+ *
+ * The difference from d_path() is that this prepends "(unreachable)"
+ * to paths which are unreachable from the current process' root.
+ */
+char *d_path_with_unreachable(const struct path *path, char *buf, int buflen)
+{
+ char *res = buf + buflen;
+ struct path root;
+ struct path tmp;
+ int error;
+
+ if (path->dentry->d_op && path->dentry->d_op->d_dname)
+ return path->dentry->d_op->d_dname(path->dentry, buf, buflen);
+
+ get_fs_root(current->fs, &root);
+ spin_lock(&dcache_lock);
+ tmp = root;
+ error = path_with_deleted(path, &tmp, &res, &buflen);
+ if (!error && !path_equal(&tmp, &root))
+ error = prepend_unreachable(&res, &buflen);
+ spin_unlock(&dcache_lock);
+ path_put(&root);
+ if (error)
+ res = ERR_PTR(error);
+
+ return res;
+}
+
/*
* Helper function for dentry_operations.d_dname() members
*/
/*
* Write full pathname from the root of the filesystem into the buffer.
*/
-char *dentry_path(struct dentry *dentry, char *buf, int buflen)
+char *__dentry_path(struct dentry *dentry, char *buf, int buflen)
{
char *end = buf + buflen;
char *retval;
- spin_lock(&dcache_lock);
prepend(&end, &buflen, "\0", 1);
- if (d_unlinked(dentry) &&
- (prepend(&end, &buflen, "//deleted", 9) != 0))
- goto Elong;
if (buflen < 1)
goto Elong;
/* Get '/' right */
retval = end;
dentry = parent;
}
+ return retval;
+Elong:
+ return ERR_PTR(-ENAMETOOLONG);
+}
+EXPORT_SYMBOL(__dentry_path);
+
+char *dentry_path(struct dentry *dentry, char *buf, int buflen)
+{
+ char *p = NULL;
+ char *retval;
+
+ spin_lock(&dcache_lock);
+ if (d_unlinked(dentry)) {
+ p = buf + buflen;
+ if (prepend(&p, &buflen, "//deleted", 10) != 0)
+ goto Elong;
+ buflen++;
+ }
+ retval = __dentry_path(dentry, buf, buflen);
spin_unlock(&dcache_lock);
+ if (!IS_ERR(retval) && p)
+ *p = '/'; /* restore '/' overriden with '\0' */
return retval;
Elong:
spin_unlock(&dcache_lock);
if (!page)
return -ENOMEM;
- read_lock(¤t->fs->lock);
- pwd = current->fs->pwd;
- path_get(&pwd);
- root = current->fs->root;
- path_get(&root);
- read_unlock(¤t->fs->lock);
+ get_fs_root_and_pwd(current->fs, &root, &pwd);
error = -ENOENT;
spin_lock(&dcache_lock);
if (!d_unlinked(pwd.dentry)) {
unsigned long len;
struct path tmp = root;
- char * cwd;
+ char *cwd = page + PAGE_SIZE;
+ int buflen = PAGE_SIZE;
- cwd = __d_path(&pwd, &tmp, page, PAGE_SIZE);
+ prepend(&cwd, &buflen, "\0", 1);
+ error = prepend_path(&pwd, &tmp, &cwd, &buflen);
spin_unlock(&dcache_lock);
- error = PTR_ERR(cwd);
- if (IS_ERR(cwd))
+ if (error)
goto out;
+ /* Unreachable from current root */
+ if (!path_equal(&tmp, &root)) {
+ error = prepend_unreachable(&cwd, &buflen);
+ if (error)
+ goto out;
+ }
+
error = -ERANGE;
len = PAGE_SIZE + page - cwd;
if (len <= size) {
git.openpandora.org / pandora-kernel.git / blobdiff