@@ -17,6 +17,7 @@ struct parent;
extern int path_to_handle (char *__path, void **__hanp, size_t *__hlen);
extern int path_to_fshandle (char *__path, void **__fshanp, size_t *__fshlen);
extern int fd_to_handle (int fd, void **hanp, size_t *hlen);
+extern int handle_to_fsfd(void *, char **);
extern int handle_to_fshandle (void *__hanp, size_t __hlen, void **__fshanp,
size_t *__fshlen);
extern void free_handle (void *__hanp, size_t __hlen);
@@ -20,6 +20,7 @@ convert.c \
crc32.c \
file_exchange.c \
fsgeom.c \
+getparents.c \
histogram.c \
list_sort.c \
linux.c \
@@ -46,6 +47,7 @@ dahashselftest.h \
div64.h \
file_exchange.h \
fsgeom.h \
+getparents.h \
histogram.h \
logging.h \
paths.h \
new file mode 100644
@@ -0,0 +1,355 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2017-2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#include "platform_defs.h"
+#include "xfs.h"
+#include "xfs_arch.h"
+#include "list.h"
+#include "paths.h"
+#include "handle.h"
+#include "libfrog/getparents.h"
+
+/* Allocate a buffer for the xfs_getparent_rec array. */
+static void *
+alloc_records(
+ struct xfs_getparents *gp,
+ size_t bufsize)
+{
+ void *buf;
+
+ if (bufsize >= UINT32_MAX) {
+ errno = ENOMEM;
+ return NULL;
+ } else if (!bufsize) {
+ bufsize = XFS_XATTR_LIST_MAX;
+ }
+
+ buf = malloc(bufsize);
+ if (!buf)
+ return NULL;
+
+ gp->gp_buffer = (uintptr_t)buf;
+ gp->gp_bufsize = bufsize;
+ return buf;
+}
+
+/* Copy a file handle. */
+static inline void
+copy_handle(
+ struct xfs_handle *dest,
+ const struct xfs_handle *src)
+{
+ memcpy(dest, src, sizeof(struct xfs_handle));
+}
+
+/* Initiate a callback for each parent pointer. */
+static int
+walk_parent_records(
+ struct xfs_getparents *gp,
+ walk_parent_fn fn,
+ void *arg)
+{
+ struct xfs_getparents_rec *gpr;
+ int ret;
+
+ if (gp->gp_oflags & XFS_GETPARENTS_OFLAG_ROOT) {
+ struct parent_rec rec = {
+ .p_flags = PARENTREC_FILE_IS_ROOT,
+ };
+
+ return fn(&rec, arg);
+ }
+
+ for (gpr = xfs_getparents_first_rec(gp);
+ gpr != NULL;
+ gpr = xfs_getparents_next_rec(gp, gpr)) {
+ struct parent_rec rec = { };
+
+ if (gpr->gpr_name[0] == 0)
+ break;
+
+ copy_handle(&rec.p_handle, &gpr->gpr_parent);
+ rec.p_name = gpr->gpr_name;
+
+ ret = fn(&rec, arg);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* Walk all parent pointers of this fd. Returns 0 or positive errno. */
+int
+fd_walk_parents(
+ int fd,
+ size_t bufsize,
+ walk_parent_fn fn,
+ void *arg)
+{
+ struct xfs_getparents gp = { };
+ void *buf;
+ int ret;
+
+ buf = alloc_records(&gp, bufsize);
+ if (!buf)
+ return errno;
+
+ while ((ret = ioctl(fd, XFS_IOC_GETPARENTS, &gp)) == 0) {
+ ret = walk_parent_records(&gp, fn, arg);
+ if (ret)
+ goto out_buf;
+ if (gp.gp_oflags & XFS_GETPARENTS_OFLAG_DONE)
+ break;
+ }
+ if (ret)
+ ret = errno;
+
+out_buf:
+ free(buf);
+ return ret;
+}
+
+/* Walk all parent pointers of this handle. Returns 0 or positive errno. */
+int
+handle_walk_parents(
+ const void *hanp,
+ size_t hlen,
+ size_t bufsize,
+ walk_parent_fn fn,
+ void *arg)
+{
+ struct xfs_getparents_by_handle gph = { };
+ void *buf;
+ char *mntpt;
+ int fd;
+ int ret;
+
+ if (hlen != sizeof(struct xfs_handle))
+ return EINVAL;
+
+ /*
+ * This function doesn't modify the handle, but we don't want to have
+ * to bump the libhandle major version just to change that.
+ */
+ fd = handle_to_fsfd((void *)hanp, &mntpt);
+ if (fd < 0)
+ return errno;
+
+ buf = alloc_records(&gph.gph_request, bufsize);
+ if (!buf)
+ return errno;
+
+ copy_handle(&gph.gph_handle, hanp);
+ while ((ret = ioctl(fd, XFS_IOC_GETPARENTS_BY_HANDLE, &gph)) == 0) {
+ ret = walk_parent_records(&gph.gph_request, fn, arg);
+ if (ret)
+ goto out_buf;
+ if (gph.gph_request.gp_oflags & XFS_GETPARENTS_OFLAG_DONE)
+ break;
+ }
+ if (ret)
+ ret = errno;
+
+out_buf:
+ free(buf);
+ return ret;
+}
+
+struct walk_ppaths_info {
+ /* Callback */
+ walk_path_fn fn;
+ void *arg;
+
+ /* Mountpoint of this filesystem. */
+ char *mntpt;
+
+ /* Path that we're constructing. */
+ struct path_list *path;
+
+ size_t ioctl_bufsize;
+};
+
+/*
+ * Recursively walk upwards through the directory tree, changing out the path
+ * components as needed. Call the callback when we have a complete path.
+ */
+static int
+find_parent_component(
+ const struct parent_rec *rec,
+ void *arg)
+{
+ struct walk_ppaths_info *wpi = arg;
+ struct path_component *pc;
+ int ret;
+
+ if (rec->p_flags & PARENTREC_FILE_IS_ROOT)
+ return wpi->fn(wpi->mntpt, wpi->path, wpi->arg);
+
+ /*
+ * If we detect a directory tree cycle, give up. We never made any
+ * guarantees about concurrent tree updates.
+ */
+ if (path_will_loop(wpi->path, rec->p_handle.ha_fid.fid_ino))
+ return 0;
+
+ pc = path_component_init(rec->p_name, rec->p_handle.ha_fid.fid_ino);
+ if (!pc)
+ return errno;
+ path_list_add_parent_component(wpi->path, pc);
+
+ ret = handle_walk_parents(&rec->p_handle, sizeof(rec->p_handle),
+ wpi->ioctl_bufsize, find_parent_component, wpi);
+
+ path_list_del_component(wpi->path, pc);
+ path_component_free(pc);
+ return ret;
+}
+
+/*
+ * Call the given function on all known paths from the vfs root to the inode
+ * described in the handle. Returns 0 for success or positive errno.
+ */
+int
+handle_walk_paths(
+ const void *hanp,
+ size_t hlen,
+ size_t ioctl_bufsize,
+ walk_path_fn fn,
+ void *arg)
+{
+ struct walk_ppaths_info wpi = {
+ .ioctl_bufsize = ioctl_bufsize,
+ };
+ int ret;
+
+ /*
+ * This function doesn't modify the handle, but we don't want to have
+ * to bump the libhandle major version just to change that.
+ */
+ ret = handle_to_fsfd((void *)hanp, &wpi.mntpt);
+ if (ret < 0)
+ return errno;
+
+ wpi.path = path_list_init();
+ if (!wpi.path)
+ return errno;
+ wpi.fn = fn;
+ wpi.arg = arg;
+
+ ret = handle_walk_parents(hanp, hlen, ioctl_bufsize,
+ find_parent_component, &wpi);
+
+ path_list_free(wpi.path);
+ return ret;
+}
+
+/*
+ * Call the given function on all known paths from the vfs root to the inode
+ * referred to by the file description. Returns 0 or positive errno.
+ */
+int
+fd_walk_paths(
+ int fd,
+ size_t ioctl_bufsize,
+ walk_path_fn fn,
+ void *arg)
+{
+ void *hanp;
+ size_t hlen;
+ int ret;
+
+ ret = fd_to_handle(fd, &hanp, &hlen);
+ if (ret)
+ return errno;
+
+ ret = handle_walk_paths(hanp, hlen, ioctl_bufsize, fn, arg);
+ free_handle(hanp, hlen);
+ return ret;
+}
+
+struct gather_path_info {
+ char *buf;
+ size_t len;
+ size_t written;
+};
+
+/* Helper that stringifies the first full path that we find. */
+static int
+path_to_string(
+ const char *mntpt,
+ const struct path_list *path,
+ void *arg)
+{
+ struct gather_path_info *gpi = arg;
+ int mntpt_len = strlen(mntpt);
+ int ret;
+
+ /* Trim trailing slashes from the mountpoint */
+ while (mntpt_len > 0 && mntpt[mntpt_len - 1] == '/')
+ mntpt_len--;
+
+ ret = snprintf(gpi->buf, gpi->len, "%.*s", mntpt_len, mntpt);
+ if (ret != mntpt_len)
+ return ENAMETOOLONG;
+ gpi->written += ret;
+
+ ret = path_list_to_string(path, gpi->buf + ret, gpi->len - ret);
+ if (ret < 0)
+ return ENAMETOOLONG;
+
+ gpi->written += ret;
+ return ECANCELED;
+}
+
+/*
+ * Return any eligible path to this file handle. Returns 0 for success or
+ * positive errno.
+ */
+int
+handle_to_path(
+ const void *hanp,
+ size_t hlen,
+ size_t ioctl_bufsize,
+ char *path,
+ size_t pathlen)
+{
+ struct gather_path_info gpi = { .buf = path, .len = pathlen };
+ int ret;
+
+ ret = handle_walk_paths(hanp, hlen, ioctl_bufsize, path_to_string,
+ &gpi);
+ if (ret && ret != ECANCELED)
+ return ret;
+ if (!gpi.written)
+ return ENODATA;
+
+ path[gpi.written] = 0;
+ return 0;
+}
+
+/*
+ * Return any eligible path to this file description. Returns 0 for success
+ * or positive errno.
+ */
+int
+fd_to_path(
+ int fd,
+ size_t ioctl_bufsize,
+ char *path,
+ size_t pathlen)
+{
+ struct gather_path_info gpi = { .buf = path, .len = pathlen };
+ int ret;
+
+ ret = fd_walk_paths(fd, ioctl_bufsize, path_to_string, &gpi);
+ if (ret && ret != ECANCELED)
+ return ret;
+ if (!gpi.written)
+ return ENODATA;
+
+ path[gpi.written] = 0;
+ return 0;
+}
new file mode 100644
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2023-2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#ifndef __LIBFROG_GETPARENTS_H_
+#define __LIBFROG_GETPARENTS_H_
+
+struct path_list;
+
+struct parent_rec {
+ /* File handle to parent directory */
+ struct xfs_handle p_handle;
+
+ /* Null-terminated directory entry name in the parent */
+ char *p_name;
+
+ /* Flags for this record; see PARENTREC_* below */
+ uint32_t p_flags;
+};
+
+/* This is the root directory. */
+#define PARENTREC_FILE_IS_ROOT (1U << 0)
+
+typedef int (*walk_parent_fn)(const struct parent_rec *rec, void *arg);
+
+int fd_walk_parents(int fd, size_t ioctl_bufsize, walk_parent_fn fn, void *arg);
+int handle_walk_parents(const void *hanp, size_t hanlen, size_t ioctl_bufsize,
+ walk_parent_fn fn, void *arg);
+
+typedef int (*walk_path_fn)(const char *mntpt, const struct path_list *path,
+ void *arg);
+
+int fd_walk_paths(int fd, size_t ioctl_bufsize, walk_path_fn fn, void *arg);
+int handle_walk_paths(const void *hanp, size_t hanlen, size_t ioctl_bufsize,
+ walk_path_fn fn, void *arg);
+
+int fd_to_path(int fd, size_t ioctl_bufsize, char *path, size_t pathlen);
+int handle_to_path(const void *hanp, size_t hlen, size_t ioctl_bufsize,
+ char *path, size_t pathlen);
+
+#endif /* __LIBFROG_GETPARENTS_H_ */
@@ -16,6 +16,7 @@
#include "input.h"
#include "projects.h"
#include <mntent.h>
+#include "list.h"
#include <limits.h>
extern char *progname;
@@ -560,3 +561,170 @@ fs_table_insert_project_path(
return error;
}
+
+/* Structured path components. */
+
+struct path_list {
+ struct list_head p_head;
+};
+
+struct path_component {
+ struct list_head pc_list;
+ uint64_t pc_ino;
+ char *pc_fname;
+};
+
+/* Initialize a path component with a given name. */
+struct path_component *
+path_component_init(
+ const char *name,
+ uint64_t ino)
+{
+ struct path_component *pc;
+
+ pc = malloc(sizeof(struct path_component));
+ if (!pc)
+ return NULL;
+ INIT_LIST_HEAD(&pc->pc_list);
+ pc->pc_fname = strdup(name);
+ if (!pc->pc_fname) {
+ free(pc);
+ return NULL;
+ }
+ pc->pc_ino = ino;
+ return pc;
+}
+
+/* Free a path component. */
+void
+path_component_free(
+ struct path_component *pc)
+{
+ free(pc->pc_fname);
+ free(pc);
+}
+
+/* Initialize a pathname or returns positive errno. */
+struct path_list *
+path_list_init(void)
+{
+ struct path_list *path;
+
+ path = malloc(sizeof(struct path_list));
+ if (!path)
+ return NULL;
+ INIT_LIST_HEAD(&path->p_head);
+ return path;
+}
+
+/* Empty out a pathname. */
+void
+path_list_free(
+ struct path_list *path)
+{
+ struct path_component *pos;
+ struct path_component *n;
+
+ list_for_each_entry_safe(pos, n, &path->p_head, pc_list) {
+ path_list_del_component(path, pos);
+ path_component_free(pos);
+ }
+ free(path);
+}
+
+/* Add a parent component to a pathname. */
+void
+path_list_add_parent_component(
+ struct path_list *path,
+ struct path_component *pc)
+{
+ list_add(&pc->pc_list, &path->p_head);
+}
+
+/* Add a component to a pathname. */
+void
+path_list_add_component(
+ struct path_list *path,
+ struct path_component *pc)
+{
+ list_add_tail(&pc->pc_list, &path->p_head);
+}
+
+/* Remove a component from a pathname. */
+void
+path_list_del_component(
+ struct path_list *path,
+ struct path_component *pc)
+{
+ list_del_init(&pc->pc_list);
+}
+
+/*
+ * Convert a pathname into a string or returns -1 if the buffer isn't long
+ * enough.
+ */
+ssize_t
+path_list_to_string(
+ const struct path_list *path,
+ char *buf,
+ size_t buflen)
+{
+ struct path_component *pos;
+ char *buf_end = buf + buflen;
+ ssize_t bytes = 0;
+ int ret;
+
+ list_for_each_entry(pos, &path->p_head, pc_list) {
+ if (buf >= buf_end)
+ return -1;
+
+ ret = snprintf(buf, buflen, "/%s", pos->pc_fname);
+ if (ret < 0 || ret >= buflen)
+ return -1;
+
+ bytes += ret;
+ buf += ret;
+ buflen -= ret;
+ }
+ return bytes;
+}
+
+/* Walk each component of a path. */
+int
+path_walk_components(
+ const struct path_list *path,
+ path_walk_fn_t fn,
+ void *arg)
+{
+ struct path_component *pos;
+ int ret;
+
+ list_for_each_entry(pos, &path->p_head, pc_list) {
+ ret = fn(pos->pc_fname, pos->pc_ino, arg);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* Will this path contain a loop if we add this inode? */
+bool
+path_will_loop(
+ const struct path_list *path_list,
+ uint64_t ino)
+{
+ struct path_component *pc;
+ unsigned int nr = 0;
+
+ list_for_each_entry(pc, &path_list->p_head, pc_list) {
+ if (pc->pc_ino == ino)
+ return true;
+
+ /* 256 path components should be enough for anyone. */
+ if (++nr > 256)
+ return true;
+ }
+
+ return false;
+}
@@ -58,4 +58,29 @@ typedef struct fs_cursor {
extern void fs_cursor_initialise(char *__dir, uint __flags, fs_cursor_t *__cp);
extern fs_path_t *fs_cursor_next_entry(fs_cursor_t *__cp);
+/* Path information. */
+
+struct path_list;
+struct path_component;
+
+struct path_component *path_component_init(const char *name, uint64_t ino);
+void path_component_free(struct path_component *pc);
+
+struct path_list *path_list_init(void);
+void path_list_free(struct path_list *path);
+void path_list_add_parent_component(struct path_list *path,
+ struct path_component *pc);
+void path_list_add_component(struct path_list *path, struct path_component *pc);
+void path_list_del_component(struct path_list *path, struct path_component *pc);
+
+ssize_t path_list_to_string(const struct path_list *path, char *buf,
+ size_t buflen);
+
+typedef int (*path_walk_fn_t)(const char *name, uint64_t ino, void *arg);
+
+int path_walk_components(const struct path_list *path, path_walk_fn_t fn,
+ void *arg);
+
+bool path_will_loop(const struct path_list *path, uint64_t ino);
+
#endif /* __LIBFROG_PATH_H__ */
@@ -29,7 +29,6 @@ typedef union {
} comarg_t;
static int obj_to_handle(char *, int, unsigned int, comarg_t, void**, size_t*);
-static int handle_to_fsfd(void *, char **);
static char *path_to_fspath(char *path);
@@ -203,8 +202,10 @@ handle_to_fshandle(
return 0;
}
-static int
-handle_to_fsfd(void *hanp, char **path)
+int
+handle_to_fsfd(
+ void *hanp,
+ char **path)
{
struct fdhash *fdhp;