Richard W.M. Jones
2012-Mar-27 15:27 UTC
[Libguestfs] [PATCH 0/3] Enable FUSE support in the API via 'mount-local' call.
This patch is just for review. It enables FUSE support in the API via two new calls, 'guestfs_mount_local' and 'guestfs_umount_local'. FUSE turns out to be very easy to deadlock (necessitating that the machine be rebooted). Running the test from the third patch is usually an effective way to demonstrate this. However I have not yet managed to produce a simple reproducer that can be reported upstream and/or understand the precise bug. Rich.
Richard W.M. Jones
2012-Mar-27 15:27 UTC
[Libguestfs] [PATCH 1/3] generator: Allow functions with no requires args, and with some optional args.
From: "Richard W.M. Jones" <rjones at redhat.com> Previously the generator disallowed such functions. --- generator/generator_fish.ml | 4 ++++ generator/generator_ocaml.ml | 31 +++++++++++++++---------------- 2 files changed, 19 insertions(+), 16 deletions(-) diff --git a/generator/generator_fish.ml b/generator/generator_fish.ml index 84f2208..c4ab69d 100644 --- a/generator/generator_fish.ml +++ b/generator/generator_fish.ml @@ -362,6 +362,10 @@ Guestfish will prompt for these separately." pr " if (argc != %d) {\n" argc_minimum; pr " fprintf (stderr, _(\"%%s should have %%d parameter(s)\\n\"), cmd, %d);\n" argc_minimum; + ) else if argc_minimum = 0 then ( + pr " if (argc > %d) {\n" argc_maximum; + pr " fprintf (stderr, _(\"%%s should have %%d-%%d parameter(s)\\n\"), cmd, %d, %d);\n" + argc_minimum argc_maximum; ) else ( pr " if (argc < %d || argc > %d) {\n" argc_minimum argc_maximum; pr " fprintf (stderr, _(\"%%s should have %%d-%%d parameter(s)\\n\"), cmd, %d, %d);\n" diff --git a/generator/generator_ocaml.ml b/generator/generator_ocaml.ml index 2353592..db8fcc4 100644 --- a/generator/generator_ocaml.ml +++ b/generator/generator_ocaml.ml @@ -162,10 +162,10 @@ val user_cancel : t -> unit You can get the {!t} handle by calling [g#]{{!guestfs.ocaml_handle}ocaml_handle}. - Note that methods that take no parameters (except the implicit handle) - get an extra unit [()] parameter. This is so you can create a - closure from the method easily. For example - [g#]{{!guestfs.get_verbose}get_verbose} [()] + Note that methods that take no required parameters + (except the implicit handle) get an extra unit [()] parameter. + This is so you can create a closure from the method easily. + For example [g#]{{!guestfs.get_verbose}get_verbose} [()] calls the method, whereas [g#get_verbose] is a function. *) class guestfs : unit -> object @@ -179,9 +179,9 @@ class guestfs : unit -> object List.iter ( function - | name, ((_, [], []) as style), _, _, _, _, _ -> - pr " method %s : unit -> " name; - generate_ocaml_function_type style; + | name, ((_, [], _) as style), _, _, _, _, _ -> + pr " method %s : " name; + generate_ocaml_function_type ~extra_unit:true style; pr "\n" | name, style, _, _, _, _, _ -> pr " method %s : " name; @@ -267,8 +267,12 @@ class guestfs () List.iter ( function - | name, (_, [], []), _, _, _, _, _ -> (* no params? add explicit unit *) - pr " method %s () = %s g\n" name name + | name, (_, [], optargs), _, _, _, _, _ -> + (* No required params? Add explicit unit. *) + let optargs + String.concat "" + (List.map (fun arg -> " ?" ^ name_of_optargt arg) optargs) in + pr " method %s%s () = %s g%s\n" name optargs name optargs | name, _, _, _, _, _, _ -> pr " method %s = %s g\n" name name ) all_functions_sorted; @@ -416,12 +420,6 @@ copy_table (char * const * argv) pr " */\n"; pr "\n"; - (* If we run into this situation, we'll need to change the - * bindings a little. - *) - if args = [] && optargs <> [] then - failwithf "ocaml bindings don't support args = [], optargs <> []"; - let params "gv" :: List.map (fun arg -> name_of_argt arg ^ "v") @@ -676,7 +674,7 @@ and generate_ocaml_prototype ?(is_external = false) name style ); pr "\n" -and generate_ocaml_function_type (ret, args, optargs) +and generate_ocaml_function_type ?(extra_unit = false) (ret, args, optargs) List.iter ( function | OBool n -> pr "?%s:bool -> " n @@ -694,6 +692,7 @@ and generate_ocaml_function_type (ret, args, optargs) | Int _ -> pr "int -> " | Int64 _ | Pointer _ -> pr "int64 -> " ) args; + if extra_unit then pr "unit -> "; (match ret with | RErr -> pr "unit" (* all errors are turned into exceptions *) | RInt _ -> pr "int" -- 1.7.9.3
Richard W.M. Jones
2012-Mar-27 15:27 UTC
[Libguestfs] [PATCH 2/3] New APIs: mount-local, umount-local (FUSE support in the API).
From: "Richard W.M. Jones" <rjones at redhat.com> Add FUSE support directly to the API. Instead of needing to use the external 'guestmount' command, you can mount the libguestfs filesystem space on a local mountpoint using an API call from any language. --- configure.ac | 11 +- fuse/Makefile.am | 2 - fuse/dircache.c | 400 ----------- fuse/dircache.h | 46 -- fuse/guestmount.c | 985 +++----------------------- fuse/guestmount.h | 2 - generator/generator_actions.ml | 60 ++ generator/generator_events.ml | 2 + ocaml/t/guestfs_400_events.ml | 3 +- po/POTFILES.in | 2 +- src/Makefile.am | 9 +- src/fuse.c | 1514 ++++++++++++++++++++++++++++++++++++++++ src/guestfs-internal.h | 9 + src/guestfs.pod | 17 + 14 files changed, 1706 insertions(+), 1356 deletions(-) delete mode 100644 fuse/dircache.c delete mode 100644 fuse/dircache.h create mode 100644 src/fuse.c diff --git a/configure.ac b/configure.ac index 1214107..ef3099e 100644 --- a/configure.ac +++ b/configure.ac @@ -696,9 +696,14 @@ AC_ARG_ENABLE([fuse], [], [enable_fuse=yes]) AS_IF([test "x$enable_fuse" != "xno"], - [PKG_CHECK_MODULES([FUSE],[fuse],,[ - enable_fuse=no - AC_MSG_WARN([FUSE library and headers are missing, so optional FUSE module won't be built])])]) + [PKG_CHECK_MODULES([FUSE],[fuse], + [AC_SUBST([FUSE_CFLAGS]) + AC_SUBST([FUSE_LIBS]) + AC_DEFINE([HAVE_FUSE],[1],[Define to 1 if you have FUSE])], + [enable_fuse=no + AC_MSG_WARN([FUSE library and headers are missing, so optional FUSE module won't be built]) + ]) + ]) AM_CONDITIONAL([HAVE_FUSE],[test "x$enable_fuse" != "xno"]) dnl Check for C++ (optional, we just use this to test the header works). diff --git a/fuse/Makefile.am b/fuse/Makefile.am index 19c498b..f9d513b 100644 --- a/fuse/Makefile.am +++ b/fuse/Makefile.am @@ -37,8 +37,6 @@ SHARED_SOURCE_FILES = \ guestmount_SOURCES = \ $(SHARED_SOURCE_FILES) \ - dircache.c \ - dircache.h \ guestmount.c \ guestmount.h diff --git a/fuse/dircache.c b/fuse/dircache.c deleted file mode 100644 index 771e313..0000000 --- a/fuse/dircache.c +++ /dev/null @@ -1,400 +0,0 @@ -/* guestmount - mount guests using libguestfs and FUSE - * Copyright (C) 2009 Red Hat Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Derived from the example program 'fusexmp.c': - * Copyright (C) 2001-2007 Miklos Szeredi <miklos at szeredi.hu> - * - * This program can be distributed under the terms of the GNU GPL. - * See the file COPYING. - */ - -#include <config.h> - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <time.h> -#include <assert.h> -#include <sys/time.h> -#include <sys/types.h> - -#include <guestfs.h> - -#include "hash.h" -#include "hash-pjw.h" - -#include "guestmount.h" -#include "dircache.h" - -/* Note on attribute caching: FUSE can cache filesystem attributes for - * short periods of time (configurable via -o attr_timeout). It - * doesn't cache xattrs, and in any case FUSE caching doesn't solve - * the problem that we have to make a series of guestfs_lstat and - * guestfs_lgetxattr calls when we first list a directory (thus, many - * round trips). - * - * For this reason, we also implement a readdir cache here which is - * invoked when a readdir call is made. readdir is modified so that - * as well as reading the directory, it also requests all the stat - * structures, xattrs and readlinks of all entries in the directory, - * and these are added to the cache here (for a short, configurable - * period of time) in anticipation that they will be needed - * immediately afterwards, which is usually the case when the user is - * doing an "ls"-like operation. - * - * You can still use FUSE attribute caching on top of this mechanism - * if you like. - */ - -struct lsc_entry { /* lstat cache entry */ - char *pathname; /* full path to the file */ - time_t timeout; /* when this entry expires */ - struct stat statbuf; /* statbuf */ -}; - -struct xac_entry { /* xattr cache entry */ - /* NB first two fields must be same as lsc_entry */ - char *pathname; /* full path to the file */ - time_t timeout; /* when this entry expires */ - struct guestfs_xattr_list *xattrs; -}; - -struct rlc_entry { /* readlink cache entry */ - /* NB first two fields must be same as lsc_entry */ - char *pathname; /* full path to the file */ - time_t timeout; /* when this entry expires */ - char *link; -}; - -static size_t -gen_hash (void const *x, size_t table_size) -{ - struct lsc_entry const *p = x; - return hash_pjw (p->pathname, table_size); -} - -static bool -gen_compare (void const *x, void const *y) -{ - struct lsc_entry const *a = x; - struct lsc_entry const *b = y; - return STREQ (a->pathname, b->pathname); -} - -static void -lsc_free (void *x) -{ - if (x) { - struct lsc_entry *p = x; - - free (p->pathname); - free (p); - } -} - -static void -xac_free (void *x) -{ - if (x) { - struct xac_entry *p = x; - - guestfs_free_xattr_list (p->xattrs); - lsc_free (x); - } -} - -static void -rlc_free (void *x) -{ - if (x) { - struct rlc_entry *p = x; - - free (p->link); - lsc_free (x); - } -} - -static Hash_table *lsc_ht, *xac_ht, *rlc_ht; - -void -init_dir_caches (void) -{ - lsc_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, lsc_free); - xac_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, xac_free); - rlc_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, rlc_free); - if (!lsc_ht || !xac_ht || !rlc_ht) { - fprintf (stderr, "guestmount: could not initialize dir cache hashtables\n"); - exit (EXIT_FAILURE); - } -} - -void -free_dir_caches (void) -{ - hash_free (lsc_ht); - hash_free (xac_ht); - hash_free (rlc_ht); -} - -struct gen_remove_data { - time_t now; - Hash_table *ht; - Hash_data_freer freer; -}; - -static bool -gen_remove_if_expired (void *x, void *data) -{ - /* XXX hash_do_for_each was observed calling this function - * with x == NULL. - */ - if (x) { - struct lsc_entry *p = x; - struct gen_remove_data *d = data; - - if (p->timeout < d->now) { - if (verbose) - fprintf (stderr, "dir cache: expiring entry %p (%s)\n", - p, p->pathname); - d->freer (hash_delete (d->ht, x)); - } - } - - return 1; -} - -static void -gen_remove_all_expired (Hash_table *ht, Hash_data_freer freer, time_t now) -{ - struct gen_remove_data data; - data.now = now; - data.ht = ht; - data.freer = freer; - - /* Careful reading of the documentation to hash _seems_ to indicate - * that this is safe, _provided_ we use the default thresholds (in - * particular, no shrink threshold). - */ - hash_do_for_each (ht, gen_remove_if_expired, &data); -} - -void -dir_cache_remove_all_expired (time_t now) -{ - gen_remove_all_expired (lsc_ht, lsc_free, now); - gen_remove_all_expired (xac_ht, xac_free, now); - gen_remove_all_expired (rlc_ht, rlc_free, now); -} - -static int -gen_replace (Hash_table *ht, struct lsc_entry *new_entry, Hash_data_freer freer) -{ - struct lsc_entry *old_entry; - - old_entry = hash_delete (ht, new_entry); - freer (old_entry); - - if (verbose && old_entry) - fprintf (stderr, "dir cache: this entry replaced old entry %p (%s)\n", - old_entry, old_entry->pathname); - - old_entry = hash_insert (ht, new_entry); - if (old_entry == NULL) { - perror ("hash_insert"); - freer (new_entry); - return -1; - } - assert (old_entry == new_entry); - - return 0; -} - -int -lsc_insert (const char *path, const char *name, time_t now, - struct stat const *statbuf) -{ - struct lsc_entry *entry; - - entry = malloc (sizeof *entry); - if (entry == NULL) { - perror ("malloc"); - return -1; - } - - size_t len = strlen (path) + strlen (name) + 2; - entry->pathname = malloc (len); - if (entry->pathname == NULL) { - perror ("malloc"); - free (entry); - return -1; - } - if (STREQ (path, "/")) - snprintf (entry->pathname, len, "/%s", name); - else - snprintf (entry->pathname, len, "%s/%s", path, name); - - memcpy (&entry->statbuf, statbuf, sizeof entry->statbuf); - - entry->timeout = now + dir_cache_timeout; - - if (verbose) - fprintf (stderr, "dir cache: inserting lstat entry %p (%s)\n", - entry, entry->pathname); - - return gen_replace (lsc_ht, entry, lsc_free); -} - -int -xac_insert (const char *path, const char *name, time_t now, - struct guestfs_xattr_list *xattrs) -{ - struct xac_entry *entry; - - entry = malloc (sizeof *entry); - if (entry == NULL) { - perror ("malloc"); - return -1; - } - - size_t len = strlen (path) + strlen (name) + 2; - entry->pathname = malloc (len); - if (entry->pathname == NULL) { - perror ("malloc"); - free (entry); - return -1; - } - if (STREQ (path, "/")) - snprintf (entry->pathname, len, "/%s", name); - else - snprintf (entry->pathname, len, "%s/%s", path, name); - - entry->xattrs = xattrs; - - entry->timeout = now + dir_cache_timeout; - - if (verbose) - fprintf (stderr, "dir cache: inserting xattr entry %p (%s)\n", - entry, entry->pathname); - - return gen_replace (xac_ht, (struct lsc_entry *) entry, xac_free); -} - -int -rlc_insert (const char *path, const char *name, time_t now, - char *link) -{ - struct rlc_entry *entry; - - entry = malloc (sizeof *entry); - if (entry == NULL) { - perror ("malloc"); - return -1; - } - - size_t len = strlen (path) + strlen (name) + 2; - entry->pathname = malloc (len); - if (entry->pathname == NULL) { - perror ("malloc"); - free (entry); - return -1; - } - if (STREQ (path, "/")) - snprintf (entry->pathname, len, "/%s", name); - else - snprintf (entry->pathname, len, "%s/%s", path, name); - - entry->link = link; - - entry->timeout = now + dir_cache_timeout; - - if (verbose) - fprintf (stderr, "dir cache: inserting readlink entry %p (%s)\n", - entry, entry->pathname); - - return gen_replace (rlc_ht, (struct lsc_entry *) entry, rlc_free); -} - -const struct stat * -lsc_lookup (const char *pathname) -{ - const struct lsc_entry key = { .pathname = bad_cast (pathname) }; - struct lsc_entry *entry; - time_t now; - - time (&now); - - entry = hash_lookup (lsc_ht, &key); - if (entry && entry->timeout >= now) - return &entry->statbuf; - else - return NULL; -} - -const struct guestfs_xattr_list * -xac_lookup (const char *pathname) -{ - const struct xac_entry key = { .pathname = bad_cast (pathname) }; - struct xac_entry *entry; - time_t now; - - time (&now); - - entry = hash_lookup (xac_ht, &key); - if (entry && entry->timeout >= now) - return entry->xattrs; - else - return NULL; -} - -const char * -rlc_lookup (const char *pathname) -{ - const struct rlc_entry key = { .pathname = bad_cast (pathname) }; - struct rlc_entry *entry; - time_t now; - - time (&now); - - entry = hash_lookup (rlc_ht, &key); - if (entry && entry->timeout >= now) - return entry->link; - else - return NULL; -} - -static void -lsc_remove (Hash_table *ht, const char *pathname, Hash_data_freer freer) -{ - const struct lsc_entry key = { .pathname = bad_cast (pathname) }; - struct lsc_entry *entry; - - entry = hash_delete (ht, &key); - - if (verbose && entry) - fprintf (stderr, "dir cache: invalidating entry %p (%s)\n", - entry, entry->pathname); - - freer (entry); -} - -void -dir_cache_invalidate (const char *path) -{ - lsc_remove (lsc_ht, path, lsc_free); - lsc_remove (xac_ht, path, xac_free); - lsc_remove (rlc_ht, path, rlc_free); -} diff --git a/fuse/dircache.h b/fuse/dircache.h deleted file mode 100644 index 76ee930..0000000 --- a/fuse/dircache.h +++ /dev/null @@ -1,46 +0,0 @@ -/* guestmount - mount guests using libguestfs and FUSE - * Copyright (C) 2009 Red Hat Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Derived from the example program 'fusexmp.c': - * Copyright (C) 2001-2007 Miklos Szeredi <miklos at szeredi.hu> - * - * This program can be distributed under the terms of the GNU GPL. - * See the file COPYING. - */ - -#ifndef GUESTMOUNT_DIRCACHE_H -#define GUESTMOUNT_DIRCACHE_H 1 - -#include <time.h> -#include <sys/stat.h> -#include <guestfs.h> - -extern void init_dir_caches (void); -extern void free_dir_caches (void); -extern void dir_cache_remove_all_expired (time_t now); -extern void dir_cache_invalidate (const char *path); - -extern int lsc_insert (const char *path, const char *name, time_t now, struct stat const *statbuf); -extern int xac_insert (const char *path, const char *name, time_t now, struct guestfs_xattr_list *xattrs); -extern int rlc_insert (const char *path, const char *name, time_t now, char *link); -extern const struct stat *lsc_lookup (const char *pathname); -extern const struct guestfs_xattr_list *xac_lookup (const char *pathname); -extern const char *rlc_lookup (const char *pathname); - -extern int dir_cache_timeout; - -#endif /* GUESTMOUNT_DIRCACHE_H */ diff --git a/fuse/guestmount.c b/fuse/guestmount.c index f6c3463..bc4762e 100644 --- a/fuse/guestmount.c +++ b/fuse/guestmount.c @@ -14,12 +14,6 @@ * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Derived from the example program 'fusexmp.c': - * Copyright (C) 2001-2007 Miklos Szeredi <miklos at szeredi.hu> - * - * This program can be distributed under the terms of the GNU GPL. - * See the file COPYING. */ #define FUSE_USE_VERSION 26 @@ -33,30 +27,18 @@ #include <string.h> #include <unistd.h> #include <getopt.h> -#include <fcntl.h> -#include <dirent.h> -#include <errno.h> #include <signal.h> -#include <time.h> -#include <assert.h> -#include <sys/time.h> -#include <sys/types.h> -#include <locale.h> -#include <libintl.h> +/* We're still using some of FUSE to handle command line options. */ #include <fuse.h> -#include <guestfs.h> + +#include "guestfs.h" #include "progname.h" +#include "ignore-value.h" #include "guestmount.h" #include "options.h" -#include "dircache.h" - -/* See <attr/xattr.h> */ -#ifndef ENOATTR -#define ENOATTR ENODATA -#endif guestfs_h *g = NULL; int read_only = 0; @@ -66,838 +48,15 @@ int inspector = 0; int keys_from_stdin = 0; int echo_keys = 0; const char *libvirt_uri; -int dir_cache_timeout = 60; -static int trace_calls = 0; - -#define TRACE_CALL(fs,...) \ - if (trace_calls) { \ - fprintf (stderr, "%s: %s (" fs ")\n", \ - program_name, __func__, __VA_ARGS__); \ - } - -static int -error (void) -{ - return -guestfs_last_errno (g); -} - -static struct guestfs_xattr_list * -copy_xattr_list (const struct guestfs_xattr *first, size_t num) -{ - struct guestfs_xattr_list *xattrs; - - xattrs = malloc (sizeof *xattrs); - if (xattrs == NULL) { - perror ("malloc"); - return NULL; - } - - xattrs->len = num; - xattrs->val = malloc (num * sizeof (struct guestfs_xattr)); - if (xattrs->val == NULL) { - perror ("malloc"); - free (xattrs); - return NULL; - } - - size_t i; - for (i = 0; i < num; ++i) { - xattrs->val[i].attrname = strdup (first[i].attrname); - xattrs->val[i].attrval_len = first[i].attrval_len; - xattrs->val[i].attrval = malloc (first[i].attrval_len); - memcpy (xattrs->val[i].attrval, first[i].attrval, first[i].attrval_len); - } - - return xattrs; -} - -static int -fg_readdir (const char *path, void *buf, fuse_fill_dir_t filler, - off_t offset, struct fuse_file_info *fi) -{ - TRACE_CALL ("%s, %p, %ld", path, buf, (long) offset); - - time_t now; - time (&now); - - dir_cache_remove_all_expired (now); - - struct guestfs_dirent_list *ents; - - ents = guestfs_readdir (g, path); - if (ents == NULL) - return error (); - - size_t i; - for (i = 0; i < ents->len; ++i) { - struct stat stat; - memset (&stat, 0, sizeof stat); - - stat.st_ino = ents->val[i].ino; - switch (ents->val[i].ftyp) { - case 'b': stat.st_mode = S_IFBLK; break; - case 'c': stat.st_mode = S_IFCHR; break; - case 'd': stat.st_mode = S_IFDIR; break; - case 'f': stat.st_mode = S_IFIFO; break; - case 'l': stat.st_mode = S_IFLNK; break; - case 'r': stat.st_mode = S_IFREG; break; - case 's': stat.st_mode = S_IFSOCK; break; - case 'u': - case '?': - default: stat.st_mode = 0; - } - - /* Copied from the example, which also ignores 'offset'. I'm - * not quite sure how this is ever supposed to work on large - * directories. XXX - */ - if (filler (buf, ents->val[i].name, &stat, 0)) - break; - } - - /* Now prepopulate the directory caches. This step is just an - * optimization, don't worry if it fails. - */ - char **names = malloc ((ents->len + 1) * sizeof (char *)); - if (names) { - for (i = 0; i < ents->len; ++i) - names[i] = ents->val[i].name; - names[i] = NULL; - - struct guestfs_stat_list *ss = guestfs_lstatlist (g, path, names); - if (ss) { - for (i = 0; i < ss->len; ++i) { - if (ss->val[i].ino >= 0) { - struct stat statbuf; - - statbuf.st_dev = ss->val[i].dev; - statbuf.st_ino = ss->val[i].ino; - statbuf.st_mode = ss->val[i].mode; - statbuf.st_nlink = ss->val[i].nlink; - statbuf.st_uid = ss->val[i].uid; - statbuf.st_gid = ss->val[i].gid; - statbuf.st_rdev = ss->val[i].rdev; - statbuf.st_size = ss->val[i].size; - statbuf.st_blksize = ss->val[i].blksize; - statbuf.st_blocks = ss->val[i].blocks; - statbuf.st_atime = ss->val[i].atime; - statbuf.st_mtime = ss->val[i].mtime; - statbuf.st_ctime = ss->val[i].ctime; - - lsc_insert (path, names[i], now, &statbuf); - } - } - guestfs_free_stat_list (ss); - } - - struct guestfs_xattr_list *xattrs = guestfs_lxattrlist (g, path, names); - if (xattrs) { - size_t ni, num; - struct guestfs_xattr *first; - struct guestfs_xattr_list *copy; - for (i = 0, ni = 0; i < xattrs->len; ++i, ++ni) { - assert (strlen (xattrs->val[i].attrname) == 0); - if (xattrs->val[i].attrval_len > 0) { - ++i; - first = &xattrs->val[i]; - num = 0; - for (; i < xattrs->len && strlen (xattrs->val[i].attrname) > 0; ++i) - num++; - - copy = copy_xattr_list (first, num); - if (copy) - xac_insert (path, names[ni], now, copy); - - i--; - } - } - guestfs_free_xattr_list (xattrs); - } - - char **links = guestfs_readlinklist (g, path, names); - if (links) { - for (i = 0; names[i] != NULL; ++i) { - if (links[i][0]) - /* Note that rlc_insert owns the string links[i] after this, */ - rlc_insert (path, names[i], now, links[i]); - else - /* which is why we have to free links[i] here. */ - free (links[i]); - } - free (links); /* free the array, not the strings */ - } - - free (names); - } - - guestfs_free_dirent_list (ents); - - return 0; -} - -static int -fg_getattr (const char *path, struct stat *statbuf) -{ - TRACE_CALL ("%s, %p", path, statbuf); - - const struct stat *buf; - - buf = lsc_lookup (path); - if (buf) { - memcpy (statbuf, buf, sizeof *statbuf); - return 0; - } - - struct guestfs_stat *r; - - r = guestfs_lstat (g, path); - if (r == NULL) - return error (); - - statbuf->st_dev = r->dev; - statbuf->st_ino = r->ino; - statbuf->st_mode = r->mode; - statbuf->st_nlink = r->nlink; - statbuf->st_uid = r->uid; - statbuf->st_gid = r->gid; - statbuf->st_rdev = r->rdev; - statbuf->st_size = r->size; - statbuf->st_blksize = r->blksize; - statbuf->st_blocks = r->blocks; - statbuf->st_atime = r->atime; - statbuf->st_mtime = r->mtime; - statbuf->st_ctime = r->ctime; - - guestfs_free_stat (r); - - return 0; -} - -/* Nautilus loves to use access(2) to test everything about a file, - * such as whether it's executable. Therefore treat this a lot like - * fg_getattr. - */ -static int -fg_access (const char *path, int mask) -{ - TRACE_CALL ("%s, %d", path, mask); - - struct stat statbuf; - int r; - - if (read_only && (mask & W_OK)) - return -EROFS; - - r = fg_getattr (path, &statbuf); - if (r < 0 || mask == F_OK) - return r; - - struct fuse_context *fuse = fuse_get_context (); - int ok = 1; - - if (mask & R_OK) - ok = ok && - ( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IRUSR - : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IRGRP - : statbuf.st_mode & S_IROTH); - if (mask & W_OK) - ok = ok && - ( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IWUSR - : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IWGRP - : statbuf.st_mode & S_IWOTH); - if (mask & X_OK) - ok = ok && - ( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IXUSR - : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IXGRP - : statbuf.st_mode & S_IXOTH); - - return ok ? 0 : -EACCES; -} - -static int -fg_readlink (const char *path, char *buf, size_t size) -{ - TRACE_CALL ("%s, %p, %zu", path, buf, size); - - const char *r; - int free_it = 0; - - r = rlc_lookup (path); - if (!r) { - r = guestfs_readlink (g, path); - if (r == NULL) - return error (); - free_it = 1; - } - - /* Note this is different from the real readlink(2) syscall. FUSE wants - * the string to be always nul-terminated, even if truncated. - */ - size_t len = strlen (r); - if (len > size - 1) - len = size - 1; - - memcpy (buf, r, len); - buf[len] = '\0'; - - if (free_it) { - char *tmp = (char *) r; - free (tmp); - } - - return 0; -} - -static int -fg_mknod (const char *path, mode_t mode, dev_t rdev) -{ - TRACE_CALL ("%s, 0%o, 0x%lx", path, mode, (long) rdev); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - r = guestfs_mknod (g, mode, major (rdev), minor (rdev), path); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_mkdir (const char *path, mode_t mode) -{ - TRACE_CALL ("%s, 0%o", path, mode); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - r = guestfs_mkdir_mode (g, path, mode); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_unlink (const char *path) -{ - TRACE_CALL ("%s", path); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - r = guestfs_rm (g, path); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_rmdir (const char *path) -{ - TRACE_CALL ("%s", path); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - r = guestfs_rmdir (g, path); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_symlink (const char *from, const char *to) -{ - TRACE_CALL ("%s, %s", from, to); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (to); - - r = guestfs_ln_s (g, from, to); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_rename (const char *from, const char *to) -{ - TRACE_CALL ("%s, %s", from, to); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (from); - dir_cache_invalidate (to); - - /* XXX It's not clear how close the 'mv' command is to the - * rename syscall. We might need to add the rename syscall - * to the guestfs(3) API. - */ - r = guestfs_mv (g, from, to); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_link (const char *from, const char *to) -{ - TRACE_CALL ("%s, %s", from, to); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (from); - dir_cache_invalidate (to); - - r = guestfs_ln (g, from, to); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_chmod (const char *path, mode_t mode) -{ - TRACE_CALL ("%s, 0%o", path, mode); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - r = guestfs_chmod (g, mode, path); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_chown (const char *path, uid_t uid, gid_t gid) -{ - TRACE_CALL ("%s, %ld, %ld", path, (long) uid, (long) gid); - - int r; - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - r = guestfs_lchown (g, uid, gid, path); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_truncate (const char *path, off_t size) -{ - TRACE_CALL ("%s, %ld", path, (long) size); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - r = guestfs_truncate_size (g, path, size); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_utimens (const char *path, const struct timespec ts[2]) -{ - TRACE_CALL ("%s, [{ %ld, %ld }, { %ld, %ld }]", - path, ts[0].tv_sec, ts[0].tv_nsec, ts[1].tv_sec, ts[1].tv_nsec); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - time_t atsecs = ts[0].tv_sec; - long atnsecs = ts[0].tv_nsec; - time_t mtsecs = ts[1].tv_sec; - long mtnsecs = ts[1].tv_nsec; - -#ifdef UTIME_NOW - if (atnsecs == UTIME_NOW) - atnsecs = -1; -#endif -#ifdef UTIME_OMIT - if (atnsecs == UTIME_OMIT) - atnsecs = -2; -#endif -#ifdef UTIME_NOW - if (mtnsecs == UTIME_NOW) - mtnsecs = -1; -#endif -#ifdef UTIME_OMIT - if (mtnsecs == UTIME_OMIT) - mtnsecs = -2; -#endif - - r = guestfs_utimens (g, path, atsecs, atnsecs, mtsecs, mtnsecs); - if (r == -1) - return error (); - - return 0; -} - -/* All this function needs to do is to check that the requested open - * flags are valid. See the notes in <fuse/fuse.h>. - */ -static int -fg_open (const char *path, struct fuse_file_info *fi) -{ - TRACE_CALL ("%s, 0%o", path, fi->flags); - - int flags = fi->flags & O_ACCMODE; - - if (read_only && flags != O_RDONLY) - return -EROFS; - - return 0; -} - -static int -fg_read (const char *path, char *buf, size_t size, off_t offset, - struct fuse_file_info *fi) -{ - TRACE_CALL ("%s, %p, %zu, %ld", path, buf, size, (long) offset); - - char *r; - size_t rsize; - - if (verbose) - fprintf (stderr, "fg_read: %s: size %zu offset %ju\n", - path, size, offset); - - /* The guestfs protocol limits size to somewhere over 2MB. We just - * reduce the requested size here accordingly and push the problem - * up to every user. http://www.jwz.org/doc/worse-is-better.html - */ - const size_t limit = 2 * 1024 * 1024; - if (size > limit) - size = limit; - - r = guestfs_pread (g, path, size, offset, &rsize); - if (r == NULL) - return error (); - - /* This should never happen, but at least it stops us overflowing - * the output buffer if it does happen. - */ - if (rsize > size) - rsize = size; - - memcpy (buf, r, rsize); - free (r); - - return rsize; -} - -static int -fg_write (const char *path, const char *buf, size_t size, - off_t offset, struct fuse_file_info *fi) -{ - TRACE_CALL ("%s, %p, %zu, %ld", path, buf, size, (long) offset); - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - /* See fg_read. */ - const size_t limit = 2 * 1024 * 1024; - if (size > limit) - size = limit; - - int r; - r = guestfs_pwrite (g, path, buf, size, offset); - if (r == -1) - return error (); - - return r; -} - -static int -fg_statfs (const char *path, struct statvfs *stbuf) -{ - TRACE_CALL ("%s, %p", path, stbuf); - - struct guestfs_statvfs *r; - - r = guestfs_statvfs (g, path); - if (r == NULL) - return error (); - - stbuf->f_bsize = r->bsize; - stbuf->f_frsize = r->frsize; - stbuf->f_blocks = r->blocks; - stbuf->f_bfree = r->bfree; - stbuf->f_bavail = r->bavail; - stbuf->f_files = r->files; - stbuf->f_ffree = r->ffree; - stbuf->f_favail = r->favail; - stbuf->f_fsid = r->fsid; - stbuf->f_flag = r->flag; - stbuf->f_namemax = r->namemax; - - guestfs_free_statvfs (r); - - return 0; -} - -static int -fg_release (const char *path, struct fuse_file_info *fi) -{ - TRACE_CALL ("%s", path); - - /* Just a stub. This method is optional and can safely be left - * unimplemented. - */ - return 0; -} - -/* Emulate this by calling sync. */ -static int fg_fsync(const char *path, int isdatasync, - struct fuse_file_info *fi) -{ - TRACE_CALL ("%s, %d", path, isdatasync); - - int r; - - r = guestfs_sync (g); - if (r == -1) - return error (); - - return 0; -} - -static int -fg_setxattr (const char *path, const char *name, const char *value, - size_t size, int flags) -{ - TRACE_CALL ("%s, %s, %p, %zu", path, name, value, size); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - /* XXX Underlying guestfs(3) API doesn't understand the flags. */ - r = guestfs_lsetxattr (g, name, value, size, path); - if (r == -1) - return error (); - - return 0; -} - -/* The guestfs(3) API for getting xattrs is much easier to use - * than the real syscall. Unfortunately we now have to emulate - * the real syscall using that API :-( - */ -static int -fg_getxattr (const char *path, const char *name, char *value, - size_t size) -{ - TRACE_CALL ("%s, %s, %p, %zu", path, name, value, size); - - const struct guestfs_xattr_list *xattrs; - int free_attrs = 0; - - xattrs = xac_lookup (path); - if (xattrs == NULL) { - xattrs = guestfs_lgetxattrs (g, path); - if (xattrs == NULL) - return error (); - free_attrs = 1; - } - - /* Find the matching attribute (index in 'i'). */ - ssize_t r; - size_t i; - for (i = 0; i < xattrs->len; ++i) { - if (STREQ (xattrs->val[i].attrname, name)) - break; - } - - if (i == xattrs->len) { /* not found */ - r = -ENOATTR; - goto out; - } - - /* The getxattr man page is unclear, but if value == NULL then we - * return the space required (the caller then makes a second syscall - * after allocating the required amount of space). If value != NULL - * then it's not clear what we should do, but it appears we should - * copy as much as possible and return -ERANGE if there's not enough - * space in the buffer. - */ - size_t sz = xattrs->val[i].attrval_len; - if (value == NULL) { - r = sz; - goto out; - } - - if (sz <= size) - r = sz; - else { - r = -ERANGE; - sz = size; - } - memcpy (value, xattrs->val[i].attrval, sz); - -out: - if (free_attrs) - guestfs_free_xattr_list ((struct guestfs_xattr_list *) xattrs); - - return r; -} - -/* Ditto as above. */ -static int -fg_listxattr (const char *path, char *list, size_t size) -{ - TRACE_CALL ("%s, %p, %zu", path, list, size); - - const struct guestfs_xattr_list *xattrs; - int free_attrs = 0; - - xattrs = xac_lookup (path); - if (xattrs == NULL) { - xattrs = guestfs_lgetxattrs (g, path); - if (xattrs == NULL) - return error (); - free_attrs = 1; - } - - /* Calculate how much space is required to hold the result. */ - size_t space = 0; - size_t len; - size_t i; - for (i = 0; i < xattrs->len; ++i) { - len = strlen (xattrs->val[i].attrname) + 1; - space += len; - } - - /* The listxattr man page is unclear, but if list == NULL then we - * return the space required (the caller then makes a second syscall - * after allocating the required amount of space). If list != NULL - * then it's not clear what we should do, but it appears we should - * copy as much as possible and return -ERANGE if there's not enough - * space in the buffer. - */ - ssize_t r; - if (list == NULL) { - r = space; - goto out; - } - - r = 0; - for (i = 0; i < xattrs->len; ++i) { - len = strlen (xattrs->val[i].attrname) + 1; - if (size >= len) { - memcpy (list, xattrs->val[i].attrname, len); - size -= len; - list += len; - r += len; - } else { - r = -ERANGE; - break; - } - } - - out: - if (free_attrs) - guestfs_free_xattr_list ((struct guestfs_xattr_list *) xattrs); - - return r; -} - -static int -fg_removexattr(const char *path, const char *name) -{ - TRACE_CALL ("%s, %s", path, name); - - int r; - - if (read_only) return -EROFS; - - dir_cache_invalidate (path); - - r = guestfs_lremovexattr (g, name, path); - if (r == -1) - return error (); - - return 0; -} - -static struct fuse_operations fg_operations = { - .getattr = fg_getattr, - .access = fg_access, - .readlink = fg_readlink, - .readdir = fg_readdir, - .mknod = fg_mknod, - .mkdir = fg_mkdir, - .symlink = fg_symlink, - .unlink = fg_unlink, - .rmdir = fg_rmdir, - .rename = fg_rename, - .link = fg_link, - .chmod = fg_chmod, - .chown = fg_chown, - .truncate = fg_truncate, - .utimens = fg_utimens, - .open = fg_open, - .read = fg_read, - .write = fg_write, - .statfs = fg_statfs, - .release = fg_release, - .fsync = fg_fsync, - .setxattr = fg_setxattr, - .getxattr = fg_getxattr, - .listxattr = fg_listxattr, - .removexattr = fg_removexattr, -}; +static void mounted (guestfs_h *g, void *vp, uint64_t event, int event_handle, int flags, const char *buf, size_t buf_len, const uint64_t *array, size_t array_len); static void __attribute__((noreturn)) fuse_help (void) { + static struct fuse_operations null_operations; const char *tmp_argv[] = { program_name, "--help", NULL }; - fuse_main (2, (char **) tmp_argv, &fg_operations, NULL); + fuse_main (2, (char **) tmp_argv, &null_operations, NULL); exit (EXIT_SUCCESS); } @@ -990,20 +149,12 @@ main (int argc, char *argv[]) int option_index; struct sigaction sa; - size_t fuse_argc = 0; - const char **fuse_argv = NULL; + int debug_calls = 0; + int dir_cache_timeout = -1; + int do_fork = 1; + char *fuse_options = NULL; -#define ADD_FUSE_ARG(str) \ - do { \ - fuse_argc ++; \ - fuse_argv = realloc (fuse_argv, (1+fuse_argc) * sizeof (char *)); \ - if (!fuse_argv) { \ - perror ("realloc"); \ - exit (EXIT_FAILURE); \ - } \ - fuse_argv[fuse_argc-1] = (str); \ - fuse_argv[fuse_argc] = NULL; \ - } while (0) + struct guestfs_mount_local_argv optargs; /* LC_ALL=C is required so we can parse error messages. */ setenv ("LC_ALL", "C", 1); @@ -1016,24 +167,12 @@ main (int argc, char *argv[]) sa.sa_flags = SA_RESTART; sigaction (SIGPIPE, &sa, NULL); - /* Various initialization. */ - init_dir_caches (); - g = guestfs_create (); if (g == NULL) { fprintf (stderr, _("guestfs_create: failed to create handle\n")); exit (EXIT_FAILURE); } - guestfs_set_recovery_proc (g, 0); - - ADD_FUSE_ARG (program_name); - /* MUST be single-threaded. You cannot have two threads accessing the - * same libguestfs handle, and opening more than one handle is likely - * to be very expensive. - */ - ADD_FUSE_ARG ("-s"); - for (;;) { c = getopt_long (argc, argv, options, long_options, &option_index); if (c == -1) break; @@ -1089,8 +228,7 @@ main (int argc, char *argv[]) break; case 'o': - ADD_FUSE_ARG ("-o"); - ADD_FUSE_ARG (optarg); + fuse_opt_add_opt_escaped (&fuse_options, optarg); break; case 'r': @@ -1111,9 +249,8 @@ main (int argc, char *argv[]) case 'x': OPTION_x; - ADD_FUSE_ARG ("-f"); - guestfs_set_recovery_proc (g, 1); - trace_calls = 1; + debug_calls = 1; + do_fork = 0; break; case HELP_OPTION: @@ -1181,6 +318,9 @@ main (int argc, char *argv[]) exit (EXIT_FAILURE); } + /* If we're forking, we can't use the recovery process. */ + guestfs_set_recovery_proc (g, !do_fork); + /* Do the guest drives and mountpoints. */ add_drives (drvs, 'a'); if (guestfs_launch (g) == -1) @@ -1196,36 +336,81 @@ main (int argc, char *argv[]) if (guestfs_umask (g, 0) == -1) exit (EXIT_FAILURE); + /* Register a GUESTFS_EVENT_MOUNTED handler. */ + r = guestfs_set_event_callback (g, mounted, GUESTFS_EVENT_MOUNTED, + 0, &do_fork); + if (r == -1) + exit (EXIT_FAILURE); + + optargs.bitmask = 0; + if (read_only) { + optargs.bitmask |= GUESTFS_MOUNT_LOCAL_READONLY_BITMASK; + optargs.readonly = 1; + } + if (debug_calls) { + optargs.bitmask |= GUESTFS_MOUNT_LOCAL_DEBUGCALLS_BITMASK; + optargs.debugcalls = 1; + } + if (dir_cache_timeout > 0) { + optargs.bitmask |= GUESTFS_MOUNT_LOCAL_CACHETIMEOUT_BITMASK; + optargs.cachetimeout = dir_cache_timeout; + } + if (fuse_options != NULL) { + optargs.bitmask |= GUESTFS_MOUNT_LOCAL_OPTIONS_BITMASK; + optargs.options = fuse_options; + } + + r = guestfs_mount_local_argv (g, argv[optind], &optargs); + + /* Cleanup. */ + guestfs_close (g); + + exit (r == 0 ? EXIT_SUCCESS : EXIT_FAILURE); +} + +static void +mounted (guestfs_h *g, + void *vp, uint64_t event, int event_handle, int flags, + const char *buf, size_t buf_len, + const uint64_t *array, size_t array_len) +{ + int *do_fork = vp; + pid_t pid; + int fd; + /* At the last minute, remove the libguestfs error handler. In code * above this point, the default error handler has been used which - * sends all errors to stderr. Now before entering FUSE itself we - * want to silence errors so we can convert them (see error() - * function above). + * sends all errors to stderr. From now on, the FUSE code will + * convert errors into error codes (errnos) when appropriate. */ guestfs_set_error_handler (g, NULL, NULL); - /* Finish off FUSE args. */ - ADD_FUSE_ARG (argv[optind]); + /* Daemonize. */ + if (*do_fork) { + pid = fork (); + if (pid == -1) { + perror ("fork"); + exit (EXIT_FAILURE); + } - /* - It says about the line containing the for-statement: - error: assuming signed overflow does not occur when simplifying conditional to constant [-Wstrict-overflow] + if (pid != 0) /* parent */ + _exit (EXIT_SUCCESS); - if (verbose) { - fprintf (stderr, "guestmount: invoking FUSE with args ["); - for (i = 0; i < fuse_argc; ++i) { - if (i > 0) fprintf (stderr, ", "); - fprintf (stderr, "%s", fuse_argv[i]); + /* Emulate what old fuse_daemonize used to do. */ + if (setsid () == -1) { + perror ("setsid"); + exit (EXIT_FAILURE); } - fprintf (stderr, "]\n"); - } - */ - - r = fuse_main (fuse_argc, (char **) fuse_argv, &fg_operations, NULL); - /* Cleanup. */ - guestfs_close (g); - free_dir_caches (); + ignore_value (chdir ("/")); - exit (r == 0 ? EXIT_SUCCESS : EXIT_FAILURE); + fd = open ("/dev/null", O_RDWR); + if (fd >= 0) { + dup2 (fd, 0); + dup2 (fd, 1); + dup2 (fd, 2); + if (fd > 2) + close (fd); + } + } } diff --git a/fuse/guestmount.h b/fuse/guestmount.h index 81d026d..a6249ec 100644 --- a/fuse/guestmount.h +++ b/fuse/guestmount.h @@ -50,6 +50,4 @@ bad_cast (char const *s) return (char *) s; } -extern int verbose; - #endif /* GUESTMOUNT_H_ */ diff --git a/generator/generator_actions.ml b/generator/generator_actions.ml index 68a7bf6..c8be6a4 100644 --- a/generator/generator_actions.ml +++ b/generator/generator_actions.ml @@ -1663,6 +1663,66 @@ This function must be called before C<guestfs_launch>."); "\ This returns the number of virtual CPUs assigned to the appliance."); + ("mount_local", (RErr, [String "localmountpoint"], [OBool "readonly"; OString "options"; OInt "cachetimeout"; OBool "debugcalls"]), -1, [], + [], (* tests in fuse subdirectory *) + "mount on the local filesystem", + "\ +This call exports the libguestfs-accessible filesystem to +a local mountpoint (directory) called C<localmountpoint>. +Ordinary reads and writes to files and directories under +C<localmountpoint> are redirected through libguestfs. + +If the optional C<readonly> flag is set to true, then +writes to the filesystem return error C<EROFS>. + +C<options> is a comma-separated list of mount options. +See L<guestmount(1)> for some useful options. + +C<cachetimeout> sets the timeout (in seconds) for cached directory +entries. The default is 60 seconds. See L<guestmount(1)> +for further information. + +If C<debugcalls> is set to true, then additional debugging +information is generated for every FUSE call. + +This is currently implemented using FUSE, and so this requires +that FUSE was available when libguestfs was compiled, and at +run time. This may require installing a kernel module and/or +adding the current user to a special C<fuse> group. See the +documentation for your distro and L<http://fuse.sf.net> for +further information. Some operating systems do not have FUSE, +or libguestfs may have been compiled without FUSE support, and +in those cases this call will return an error. + +The C<guestfs_mount_local> call I<does not> return until the +filesystem is I<unmounted> (see C<guestfs_umount_local>). +The current thread is involved with the processing of +filesystem requests. To access the filesystem you need +to use another thread or process. B<Note> you must I<not> +make concurrent libguestfs calls on the same handle from +another thread, except for C<guestfs_umount_local>. + +The mountpoint is not immediately available because mounting +the filesystem takes some time. When the mountpoint +is ready to use, the C<MOUNTED> event is raised in the +current thread. When using this call, it is almost mandatory +that you register a C<MOUNTED> event callback (see +L<guestfs(3)/SETTING CALLBACKS TO HANDLE EVENTS>). FUSE +processing does not begin until the C<MOUNTED> callback returns. + +To unmount the filesystem, call C<guestfs_umount_local>. +This may be called from another thread (as a special +exception to ordinary libguestfs rules)."); + + ("umount_local", (RErr, [], [OBool "retry"]), -1, [], + [], (* tests in fuse subdirectory *) + "unmount a locally mounted filesystem", + "\ +If libguestfs is exporting the filesystem on a local +mountpoint, then this unmounts it. + +See C<guestfs_mount_local> for full documentation."); + ] (* daemon_functions are any functions which cause some action diff --git a/generator/generator_events.ml b/generator/generator_events.ml index df74af3..8ab2aae 100644 --- a/generator/generator_events.ml +++ b/generator/generator_events.ml @@ -37,6 +37,8 @@ let events = [ "trace"; (* call trace messages *) "enter"; (* enter a function *) + + "mounted"; (* local filesystem mounted and ready *) ] let events = mapi (fun i name -> name, 1 lsl i) events diff --git a/ocaml/t/guestfs_400_events.ml b/ocaml/t/guestfs_400_events.ml index 4585a09..2897b2d 100644 --- a/ocaml/t/guestfs_400_events.ml +++ b/ocaml/t/guestfs_400_events.ml @@ -28,7 +28,8 @@ let log g ev eh buf array | Guestfs.EVENT_APPLIANCE -> "appliance" | Guestfs.EVENT_LIBRARY -> "library" | Guestfs.EVENT_TRACE -> "trace" - | Guestfs.EVENT_ENTER -> "enter" in + | Guestfs.EVENT_ENTER -> "enter" + | Guestfs.EVENT_MOUNTED -> "mounted" in let eh : int = Obj.magic eh in diff --git a/po/POTFILES.in b/po/POTFILES.in index 620d68f..1f0bb36 100644 --- a/po/POTFILES.in +++ b/po/POTFILES.in @@ -129,7 +129,6 @@ fish/tilde.c fish/time.c fish/virt.c format/format.c -fuse/dircache.c fuse/guestmount.c gobject/guestfs-gobject.c inspector/virt-inspector.c @@ -155,6 +154,7 @@ src/errnostring.c src/errnostring_gperf.c src/events.c src/filearch.c +src/fuse.c src/guestfs.c src/inspect.c src/inspect_apps.c diff --git a/src/Makefile.am b/src/Makefile.am index b91ffc1..a7fcbac 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -1,5 +1,5 @@ # libguestfs -# Copyright (C) 2010 Red Hat Inc. +# Copyright (C) 2010-2012 Red Hat Inc. # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by @@ -139,6 +139,7 @@ libguestfs_la_SOURCES = \ listfs.c \ match.c \ proto.c \ + fuse.c \ virt.c \ libguestfs.syms @@ -169,6 +170,12 @@ libguestfs_la_CFLAGS = \ libguestfs_la_CPPFLAGS = -I$(top_srcdir)/gnulib/lib -I$(top_builddir)/gnulib/lib +if HAVE_FUSE +# XXX Unfortunately FUSE_CFLAGS defines _FILE_OFFSET_BITS=64. +libguestfs_la_CFLAGS += $(FUSE_CFLAGS) +libguestfs_la_LIBADD += $(FUSE_LIBS) -lulockmgr +endif + if HAVE_RPCGEN guestfs_protocol.c: guestfs_protocol.x rm -f $@-t $@-t2 diff --git a/src/fuse.c b/src/fuse.c new file mode 100644 index 0000000..2c2c3bc --- /dev/null +++ b/src/fuse.c @@ -0,0 +1,1514 @@ +/* libguestfs + * Copyright (C) 2009-2012 Red Hat Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <errno.h> +#include <sys/types.h> +#include <sys/wait.h> + +/* See <attr/xattr.h> */ +#ifndef ENOATTR +#define ENOATTR ENODATA +#endif + +#define FUSE_USE_VERSION 26 + +#if HAVE_FUSE +#include <fuse.h> +#include <fuse_lowlevel.h> +#endif + +#include "cloexec.h" +#include "glthread/lock.h" +#include "hash.h" +#include "hash-pjw.h" + +#include "guestfs.h" +#include "guestfs-internal.h" +#include "guestfs-internal-actions.h" +#include "guestfs_protocol.h" + +#if HAVE_FUSE + +/* Functions handling the directory cache. */ +static int init_dir_caches (guestfs_h *); +static void free_dir_caches (guestfs_h *); +static void dir_cache_remove_all_expired (guestfs_h *, time_t now); +static void dir_cache_invalidate (guestfs_h *, const char *path); +static int lsc_insert (guestfs_h *, const char *path, const char *name, time_t now, struct stat const *statbuf); +static int xac_insert (guestfs_h *, const char *path, const char *name, time_t now, struct guestfs_xattr_list *xattrs); +static int rlc_insert (guestfs_h *, const char *path, const char *name, time_t now, char *link); +static const struct stat *lsc_lookup (guestfs_h *, const char *pathname); +static const struct guestfs_xattr_list *xac_lookup (guestfs_h *, const char *pathname); +static const char *rlc_lookup (guestfs_h *, const char *pathname); + +/* This lock protects access to g->localmountpoint. */ +gl_lock_define_initialized (static, mount_local_lock); + +/* Private data passed around in the FUSE context. */ +struct mount_local_private { + guestfs_h *g; /* The guestfs handle. */ + int read_only; /* If mounted read-only. */ + int debug_calls; /* Extra debug info on each FUSE call. */ +}; + +#define DECL_PRIV() struct mount_local_private *priv = fuse_get_context()->private_data +#define DEBUG_CALL(fs,...) \ + if (priv->debug_calls) { \ + debug (priv->g, \ + "%s: %s (" fs ")\n", \ + priv->g->localmountpoint, __func__, ## __VA_ARGS__); \ + } + +#define RETURN_ERRNO return -guestfs_last_errno (priv->g) + +static struct guestfs_xattr_list * +copy_xattr_list (const struct guestfs_xattr *first, size_t num) +{ + struct guestfs_xattr_list *xattrs; + + xattrs = malloc (sizeof *xattrs); + if (xattrs == NULL) { + perror ("malloc"); + return NULL; + } + + xattrs->len = num; + xattrs->val = malloc (num * sizeof (struct guestfs_xattr)); + if (xattrs->val == NULL) { + perror ("malloc"); + free (xattrs); + return NULL; + } + + size_t i; + for (i = 0; i < num; ++i) { + xattrs->val[i].attrname = strdup (first[i].attrname); + xattrs->val[i].attrval_len = first[i].attrval_len; + xattrs->val[i].attrval = malloc (first[i].attrval_len); + memcpy (xattrs->val[i].attrval, first[i].attrval, first[i].attrval_len); + } + + return xattrs; +} + +static int +mount_local_readdir (const char *path, void *buf, fuse_fill_dir_t filler, + off_t offset, struct fuse_file_info *fi) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %p, %ld", path, buf, (long) offset); + + time_t now; + time (&now); + + dir_cache_remove_all_expired (priv->g, now); + + struct guestfs_dirent_list *ents; + + ents = guestfs_readdir (priv->g, path); + if (ents == NULL) + RETURN_ERRNO; + + size_t i; + for (i = 0; i < ents->len; ++i) { + struct stat stat; + memset (&stat, 0, sizeof stat); + + stat.st_ino = ents->val[i].ino; + switch (ents->val[i].ftyp) { + case 'b': stat.st_mode = S_IFBLK; break; + case 'c': stat.st_mode = S_IFCHR; break; + case 'd': stat.st_mode = S_IFDIR; break; + case 'f': stat.st_mode = S_IFIFO; break; + case 'l': stat.st_mode = S_IFLNK; break; + case 'r': stat.st_mode = S_IFREG; break; + case 's': stat.st_mode = S_IFSOCK; break; + case 'u': + case '?': + default: stat.st_mode = 0; + } + + /* Copied from the example, which also ignores 'offset'. I'm + * not quite sure how this is ever supposed to work on large + * directories. XXX + */ + if (filler (buf, ents->val[i].name, &stat, 0)) + break; + } + + /* Now prepopulate the directory caches. This step is just an + * optimization, don't worry if it fails. + */ + char **names = malloc ((ents->len + 1) * sizeof (char *)); + if (names) { + for (i = 0; i < ents->len; ++i) + names[i] = ents->val[i].name; + names[i] = NULL; + + struct guestfs_stat_list *ss = guestfs_lstatlist (priv->g, path, names); + if (ss) { + for (i = 0; i < ss->len; ++i) { + if (ss->val[i].ino >= 0) { + struct stat statbuf; + + statbuf.st_dev = ss->val[i].dev; + statbuf.st_ino = ss->val[i].ino; + statbuf.st_mode = ss->val[i].mode; + statbuf.st_nlink = ss->val[i].nlink; + statbuf.st_uid = ss->val[i].uid; + statbuf.st_gid = ss->val[i].gid; + statbuf.st_rdev = ss->val[i].rdev; + statbuf.st_size = ss->val[i].size; + statbuf.st_blksize = ss->val[i].blksize; + statbuf.st_blocks = ss->val[i].blocks; + statbuf.st_atime = ss->val[i].atime; + statbuf.st_mtime = ss->val[i].mtime; + statbuf.st_ctime = ss->val[i].ctime; + + lsc_insert (priv->g, path, names[i], now, &statbuf); + } + } + guestfs_free_stat_list (ss); + } + + struct guestfs_xattr_list *xattrs = guestfs_lxattrlist (priv->g, path, names); + if (xattrs) { + size_t ni, num; + struct guestfs_xattr *first; + struct guestfs_xattr_list *copy; + for (i = 0, ni = 0; i < xattrs->len; ++i, ++ni) { + /* assert (strlen (xattrs->val[i].attrname) == 0); */ + if (xattrs->val[i].attrval_len > 0) { + ++i; + first = &xattrs->val[i]; + num = 0; + for (; i < xattrs->len && strlen (xattrs->val[i].attrname) > 0; ++i) + num++; + + copy = copy_xattr_list (first, num); + if (copy) + xac_insert (priv->g, path, names[ni], now, copy); + + i--; + } + } + guestfs_free_xattr_list (xattrs); + } + + char **links = guestfs_readlinklist (priv->g, path, names); + if (links) { + for (i = 0; names[i] != NULL; ++i) { + if (links[i][0]) + /* Note that rlc_insert owns the string links[i] after this, */ + rlc_insert (priv->g, path, names[i], now, links[i]); + else + /* which is why we have to free links[i] here. */ + free (links[i]); + } + free (links); /* free the array, not the strings */ + } + + free (names); + } + + guestfs_free_dirent_list (ents); + + return 0; +} + +static int +mount_local_getattr (const char *path, struct stat *statbuf) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %p", path, statbuf); + + const struct stat *buf; + + buf = lsc_lookup (priv->g, path); + if (buf) { + memcpy (statbuf, buf, sizeof *statbuf); + return 0; + } + + struct guestfs_stat *r; + + r = guestfs_lstat (priv->g, path); + if (r == NULL) + RETURN_ERRNO; + + statbuf->st_dev = r->dev; + statbuf->st_ino = r->ino; + statbuf->st_mode = r->mode; + statbuf->st_nlink = r->nlink; + statbuf->st_uid = r->uid; + statbuf->st_gid = r->gid; + statbuf->st_rdev = r->rdev; + statbuf->st_size = r->size; + statbuf->st_blksize = r->blksize; + statbuf->st_blocks = r->blocks; + statbuf->st_atime = r->atime; + statbuf->st_mtime = r->mtime; + statbuf->st_ctime = r->ctime; + + guestfs_free_stat (r); + + return 0; +} + +/* Nautilus loves to use access(2) to test everything about a file, + * such as whether it's executable. Therefore treat this a lot like + * mount_local_getattr. + */ +static int +mount_local_access (const char *path, int mask) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %d", path, mask); + + struct stat statbuf; + int r; + + if (priv->read_only && (mask & W_OK)) + return -EROFS; + + r = mount_local_getattr (path, &statbuf); + if (r < 0 || mask == F_OK) + return r; + + struct fuse_context *fuse = fuse_get_context (); + int ok = 1; + + if (mask & R_OK) + ok = ok && + ( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IRUSR + : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IRGRP + : statbuf.st_mode & S_IROTH); + if (mask & W_OK) + ok = ok && + ( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IWUSR + : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IWGRP + : statbuf.st_mode & S_IWOTH); + if (mask & X_OK) + ok = ok && + ( fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IXUSR + : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IXGRP + : statbuf.st_mode & S_IXOTH); + + return ok ? 0 : -EACCES; +} + +static int +mount_local_readlink (const char *path, char *buf, size_t size) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %p, %zu", path, buf, size); + + const char *r; + int free_it = 0; + + r = rlc_lookup (priv->g, path); + if (!r) { + r = guestfs_readlink (priv->g, path); + if (r == NULL) + RETURN_ERRNO; + free_it = 1; + } + + /* Note this is different from the real readlink(2) syscall. FUSE wants + * the string to be always nul-terminated, even if truncated. + */ + size_t len = strlen (r); + if (len > size - 1) + len = size - 1; + + memcpy (buf, r, len); + buf[len] = '\0'; + + if (free_it) { + char *tmp = (char *) r; + free (tmp); + } + + return 0; +} + +static int +mount_local_mknod (const char *path, mode_t mode, dev_t rdev) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, 0%o, 0x%lx", path, mode, (long) rdev); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + r = guestfs_mknod (priv->g, mode, major (rdev), minor (rdev), path); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_mkdir (const char *path, mode_t mode) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, 0%o", path, mode); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + r = guestfs_mkdir_mode (priv->g, path, mode); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_unlink (const char *path) +{ + DECL_PRIV (); + DEBUG_CALL ("%s", path); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + r = guestfs_rm (priv->g, path); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_rmdir (const char *path) +{ + DECL_PRIV (); + DEBUG_CALL ("%s", path); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + r = guestfs_rmdir (priv->g, path); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_symlink (const char *from, const char *to) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %s", from, to); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, to); + + r = guestfs_ln_s (priv->g, from, to); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_rename (const char *from, const char *to) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %s", from, to); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, from); + dir_cache_invalidate (priv->g, to); + + /* XXX It's not clear how close the 'mv' command is to the + * rename syscall. We might need to add the rename syscall + * to the guestfs(3) API. + */ + r = guestfs_mv (priv->g, from, to); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_link (const char *from, const char *to) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %s", from, to); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, from); + dir_cache_invalidate (priv->g, to); + + r = guestfs_ln (priv->g, from, to); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_chmod (const char *path, mode_t mode) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, 0%o", path, mode); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + r = guestfs_chmod (priv->g, mode, path); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_chown (const char *path, uid_t uid, gid_t gid) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %ld, %ld", path, (long) uid, (long) gid); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + r = guestfs_lchown (priv->g, uid, gid, path); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_truncate (const char *path, off_t size) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %ld", path, (long) size); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + r = guestfs_truncate_size (priv->g, path, size); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_utimens (const char *path, const struct timespec ts[2]) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, [{ %ld, %ld }, { %ld, %ld }]", + path, ts[0].tv_sec, ts[0].tv_nsec, ts[1].tv_sec, ts[1].tv_nsec); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + time_t atsecs = ts[0].tv_sec; + long atnsecs = ts[0].tv_nsec; + time_t mtsecs = ts[1].tv_sec; + long mtnsecs = ts[1].tv_nsec; + +#ifdef UTIME_NOW + if (atnsecs == UTIME_NOW) + atnsecs = -1; +#endif +#ifdef UTIME_OMIT + if (atnsecs == UTIME_OMIT) + atnsecs = -2; +#endif +#ifdef UTIME_NOW + if (mtnsecs == UTIME_NOW) + mtnsecs = -1; +#endif +#ifdef UTIME_OMIT + if (mtnsecs == UTIME_OMIT) + mtnsecs = -2; +#endif + + r = guestfs_utimens (priv->g, path, atsecs, atnsecs, mtsecs, mtnsecs); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +/* All this function needs to do is to check that the requested open + * flags are valid. See the notes in <fuse/fuse.h>. + */ +static int +mount_local_open (const char *path, struct fuse_file_info *fi) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, 0%o", path, fi->flags); + + int flags = fi->flags & O_ACCMODE; + + if (priv->read_only && flags != O_RDONLY) + return -EROFS; + + return 0; +} + +static int +mount_local_read (const char *path, char *buf, size_t size, off_t offset, + struct fuse_file_info *fi) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %p, %zu, %ld", path, buf, size, (long) offset); + + char *r; + size_t rsize; + + debug (priv->g, + "mount_local_read: %s: size %zu offset %ju\n", path, size, offset); + + /* The guestfs protocol limits size to somewhere over 2MB. We just + * reduce the requested size here accordingly and push the problem + * up to every user. http://www.jwz.org/doc/worse-is-better.html + */ + const size_t limit = 2 * 1024 * 1024; + if (size > limit) + size = limit; + + r = guestfs_pread (priv->g, path, size, offset, &rsize); + if (r == NULL) + RETURN_ERRNO; + + /* This should never happen, but at least it stops us overflowing + * the output buffer if it does happen. + */ + if (rsize > size) + rsize = size; + + memcpy (buf, r, rsize); + free (r); + + return rsize; +} + +static int +mount_local_write (const char *path, const char *buf, size_t size, + off_t offset, struct fuse_file_info *fi) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %p, %zu, %ld", path, buf, size, (long) offset); + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + /* See mount_local_read. */ + const size_t limit = 2 * 1024 * 1024; + if (size > limit) + size = limit; + + int r; + r = guestfs_pwrite (priv->g, path, buf, size, offset); + if (r == -1) + RETURN_ERRNO; + + return r; +} + +static int +mount_local_statfs (const char *path, struct statvfs *stbuf) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %p", path, stbuf); + + struct guestfs_statvfs *r; + + r = guestfs_statvfs (priv->g, path); + if (r == NULL) + RETURN_ERRNO; + + stbuf->f_bsize = r->bsize; + stbuf->f_frsize = r->frsize; + stbuf->f_blocks = r->blocks; + stbuf->f_bfree = r->bfree; + stbuf->f_bavail = r->bavail; + stbuf->f_files = r->files; + stbuf->f_ffree = r->ffree; + stbuf->f_favail = r->favail; + stbuf->f_fsid = r->fsid; + stbuf->f_flag = r->flag; + stbuf->f_namemax = r->namemax; + + guestfs_free_statvfs (r); + + return 0; +} + +static int +mount_local_release (const char *path, struct fuse_file_info *fi) +{ + DECL_PRIV (); + DEBUG_CALL ("%s", path); + + /* Just a stub. This method is optional and can safely be left + * unimplemented. + */ + return 0; +} + +/* Emulate this by calling sync. */ +static int +mount_local_fsync (const char *path, int isdatasync, + struct fuse_file_info *fi) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %d", path, isdatasync); + + int r; + + r = guestfs_sync (priv->g); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static int +mount_local_setxattr (const char *path, const char *name, const char *value, + size_t size, int flags) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %s, %p, %zu", path, name, value, size); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + /* XXX Underlying guestfs(3) API doesn't understand the flags. */ + r = guestfs_lsetxattr (priv->g, name, value, size, path); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +/* The guestfs(3) API for getting xattrs is much easier to use + * than the real syscall. Unfortunately we now have to emulate + * the real syscall using that API :-( + */ +static int +mount_local_getxattr (const char *path, const char *name, char *value, + size_t size) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %s, %p, %zu", path, name, value, size); + + const struct guestfs_xattr_list *xattrs; + int free_attrs = 0; + + xattrs = xac_lookup (priv->g, path); + if (xattrs == NULL) { + xattrs = guestfs_lgetxattrs (priv->g, path); + if (xattrs == NULL) + RETURN_ERRNO; + free_attrs = 1; + } + + /* Find the matching attribute (index in 'i'). */ + ssize_t r; + size_t i; + for (i = 0; i < xattrs->len; ++i) { + if (STREQ (xattrs->val[i].attrname, name)) + break; + } + + if (i == xattrs->len) { /* not found */ + r = -ENOATTR; + goto out; + } + + /* The getxattr man page is unclear, but if value == NULL then we + * return the space required (the caller then makes a second syscall + * after allocating the required amount of space). If value != NULL + * then it's not clear what we should do, but it appears we should + * copy as much as possible and return -ERANGE if there's not enough + * space in the buffer. + */ + size_t sz = xattrs->val[i].attrval_len; + if (value == NULL) { + r = sz; + goto out; + } + + if (sz <= size) + r = sz; + else { + r = -ERANGE; + sz = size; + } + memcpy (value, xattrs->val[i].attrval, sz); + +out: + if (free_attrs) + guestfs_free_xattr_list ((struct guestfs_xattr_list *) xattrs); + + return r; +} + +/* Ditto as above. */ +static int +mount_local_listxattr (const char *path, char *list, size_t size) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %p, %zu", path, list, size); + + const struct guestfs_xattr_list *xattrs; + int free_attrs = 0; + + xattrs = xac_lookup (priv->g, path); + if (xattrs == NULL) { + xattrs = guestfs_lgetxattrs (priv->g, path); + if (xattrs == NULL) + RETURN_ERRNO; + free_attrs = 1; + } + + /* Calculate how much space is required to hold the result. */ + size_t space = 0; + size_t len; + size_t i; + for (i = 0; i < xattrs->len; ++i) { + len = strlen (xattrs->val[i].attrname) + 1; + space += len; + } + + /* The listxattr man page is unclear, but if list == NULL then we + * return the space required (the caller then makes a second syscall + * after allocating the required amount of space). If list != NULL + * then it's not clear what we should do, but it appears we should + * copy as much as possible and return -ERANGE if there's not enough + * space in the buffer. + */ + ssize_t r; + if (list == NULL) { + r = space; + goto out; + } + + r = 0; + for (i = 0; i < xattrs->len; ++i) { + len = strlen (xattrs->val[i].attrname) + 1; + if (size >= len) { + memcpy (list, xattrs->val[i].attrname, len); + size -= len; + list += len; + r += len; + } else { + r = -ERANGE; + break; + } + } + + out: + if (free_attrs) + guestfs_free_xattr_list ((struct guestfs_xattr_list *) xattrs); + + return r; +} + +static int +mount_local_removexattr(const char *path, const char *name) +{ + DECL_PRIV (); + DEBUG_CALL ("%s, %s", path, name); + + int r; + + if (priv->read_only) return -EROFS; + + dir_cache_invalidate (priv->g, path); + + r = guestfs_lremovexattr (priv->g, name, path); + if (r == -1) + RETURN_ERRNO; + + return 0; +} + +static struct fuse_operations mount_local_operations = { + .getattr = mount_local_getattr, + .access = mount_local_access, + .readlink = mount_local_readlink, + .readdir = mount_local_readdir, + .mknod = mount_local_mknod, + .mkdir = mount_local_mkdir, + .symlink = mount_local_symlink, + .unlink = mount_local_unlink, + .rmdir = mount_local_rmdir, + .rename = mount_local_rename, + .link = mount_local_link, + .chmod = mount_local_chmod, + .chown = mount_local_chown, + .truncate = mount_local_truncate, + .utimens = mount_local_utimens, + .open = mount_local_open, + .read = mount_local_read, + .write = mount_local_write, + .statfs = mount_local_statfs, + .release = mount_local_release, + .fsync = mount_local_fsync, + .setxattr = mount_local_setxattr, + .getxattr = mount_local_getxattr, + .listxattr = mount_local_listxattr, + .removexattr = mount_local_removexattr, +}; + +int +guestfs__mount_local (guestfs_h *g, const char *localmountpoint, + const struct guestfs_mount_local_argv *optargs) +{ + const char *t; + struct fuse_args args = FUSE_ARGS_INIT (0, NULL); + struct mount_local_private private_data; + struct fuse_chan *ch; + struct fuse *fuse; + int r, fd; + + /* You can only mount each handle in one place in one thread. */ + gl_lock_lock (mount_local_lock); + t = g->localmountpoint; + gl_lock_unlock (mount_local_lock); + if (t) { + error (g, _("filesystem is already mounted in another thread")); + return -1; + } + + private_data.g = g; + if (optargs->bitmask & GUESTFS_MOUNT_LOCAL_READONLY_BITMASK) + private_data.read_only = optargs->readonly; + else + private_data.read_only = 0; + if (optargs->bitmask & GUESTFS_MOUNT_LOCAL_CACHETIMEOUT_BITMASK) + g->dir_cache_timeout = optargs->cachetimeout; + else + g->dir_cache_timeout = 60; + if (optargs->bitmask & GUESTFS_MOUNT_LOCAL_DEBUGCALLS_BITMASK) + private_data.debug_calls = optargs->debugcalls; + else + private_data.debug_calls = 0; + + /* Initialize the directory caches. */ + if (init_dir_caches (g) == -1) + return -1; + + /* Create the FUSE 'args'. */ + /* XXX we don't have a program name */ + if (fuse_opt_add_arg (&args, "guestfs_mount_local") == -1) { + arg_error: + perrorf (g, _("fuse_opt_add_arg: %s"), localmountpoint); + fuse_opt_free_args (&args); + free_dir_caches (g); + return -1; + } + + if (optargs->bitmask & GUESTFS_MOUNT_LOCAL_OPTIONS_BITMASK) { + if (fuse_opt_add_arg (&args, "-o") == -1 || + fuse_opt_add_arg (&args, optargs->options) == -1) + goto arg_error; + } + + /* Create the FUSE mountpoint. */ + ch = fuse_mount (localmountpoint, &args); + if (ch == NULL) { + perrorf (g, _("fuse_mount: %s"), localmountpoint); + fuse_opt_free_args (&args); + free_dir_caches (g); + return -1; + } + + /* Set F_CLOEXEC on the channel. XXX libfuse should do this. */ + fd = fuse_chan_fd (ch); + if (fd >= 0) + set_cloexec_flag (fd, 1); + + /* Create the FUSE handle. */ + fuse = fuse_new (ch, &args, + &mount_local_operations, sizeof mount_local_operations, + &private_data); + if (!fuse) { + perrorf (g, _("fuse_new: %s"), localmountpoint); + fuse_unmount (localmountpoint, ch); + fuse_opt_free_args (&args); + free_dir_caches (g); + return -1; + } + + /* Since it looks like this will succeed, set g->localmountpoint in + * the handle. + */ + gl_lock_lock (mount_local_lock); + g->localmountpoint = localmountpoint; + gl_lock_unlock (mount_local_lock); + + /* Emit the MOUNTED event. */ + guestfs___call_callbacks_message (g, GUESTFS_EVENT_MOUNTED, + localmountpoint, strlen (localmountpoint)); + + /* Enter the main loop. */ + r = fuse_loop (fuse); + if (r != 0) + perrorf (g, _("fuse_loop: %s"), localmountpoint); + + gl_lock_lock (mount_local_lock); + g->localmountpoint = NULL; + gl_lock_unlock (mount_local_lock); + + fuse_destroy (fuse); /* also destroys 'ch' */ + free_dir_caches (g); + fuse_opt_free_args (&args); + + /* By inspection, I found that fuse_loop only returns 0 or -1, but + * don't rely on this in future. + */ + return r == 0 ? 0 : -1; +} + +static int do_fusermount (guestfs_h *g, const char *localmountpoint, int error_fd); + +int +guestfs__umount_local (guestfs_h *g, + const struct guestfs_umount_local_argv *optargs) +{ + size_t i, tries; + char *localmountpoint; + char *fusermount_log = NULL; + int error_fd = -1; + int ret = -1; + + /* How many times should we try the fusermount command? */ + if (optargs->bitmask & GUESTFS_UMOUNT_LOCAL_RETRY_BITMASK) + tries = optargs->retry ? 5 : 1; + else + tries = 1; + + /* Make a local copy of g->localmountpoint. It could be freed from + * under us by another thread, except when we are holding the lock. + */ + gl_lock_lock (mount_local_lock); + if (g->localmountpoint) + localmountpoint = safe_strdup (g, g->localmountpoint); + else + localmountpoint = NULL; + gl_lock_unlock (mount_local_lock); + + if (!localmountpoint) { + error (g, _("no filesystem is mounted")); + goto out; + } + + /* Send all errors from fusermount to a temporary file. Only after + * all 'tries' have failed do we print the contents of this file. A + * temporary failure when retry == true will not cause any error. + */ + fusermount_log = safe_asprintf (g, "%s/fusermount.log", g->tmpdir); + error_fd = open (fusermount_log, + O_RDWR|O_CREAT|O_TRUNC|O_NOCTTY /* not O_CLOEXEC */, + 0600); + if (error_fd == -1) { + perrorf (g, _("open: %s"), fusermount_log); + goto out; + } + + for (i = 0; i < tries; ++i) { + int r; + + r = do_fusermount (g, localmountpoint, error_fd); + if (r == -1) + goto out; + if (r) { + /* External fusermount succeeded. Note that the original thread + * is responsible for setting g->localmountpoint to NULL. + */ + ret = 0; + break; + } + + sleep (1); + } + + if (ret == -1) { /* fusermount failed */ + char error_message[4096]; + ssize_t n; + + /* Get the error message from the log file. */ + if (lseek (error_fd, 0, SEEK_SET) >= 0 && + (n = read (error_fd, error_message, sizeof error_message - 1)) > 0) { + while (n > 0 && error_message[n-1] == '\n') + n--; + error_message[n] = '\0'; + } else { + snprintf (error_message, sizeof error_message, + "(fusermount error could not be preserved)"); + } + + error (g, _("fusermount failed: %s: %s"), localmountpoint, error_message); + goto out; + } + + out: + if (error_fd >= 0) close (error_fd); + if (fusermount_log) { + unlink (fusermount_log); + free (fusermount_log); + } + free (localmountpoint); + return ret; +} + +static int +do_fusermount (guestfs_h *g, const char *localmountpoint, int error_fd) +{ + pid_t pid; + int status; + + pid = fork (); + if (pid == -1) { + perrorf (g, "fork"); + return -1; + } + + if (pid == 0) { /* child */ + /* Ensure stdout and stderr point to the error_fd. */ + dup2 (error_fd, STDOUT_FILENO); + dup2 (error_fd, STDERR_FILENO); + close (error_fd); + execlp ("fusermount", "fusermount", "-u", localmountpoint, NULL); + perror ("exec: fusermount"); + _exit (EXIT_FAILURE); + } + + /* Parent. */ + if (waitpid (pid, &status, 0) == -1) { + perrorf (g, "waitpid"); + return -1; + } + + if (!WIFEXITED (status) || WEXITSTATUS (status) != EXIT_SUCCESS) + return 0; /* it failed to unmount the mountpoint */ + + return 1; /* unmount was successful */ +} + +/* Functions handling the directory cache. + * + * Note on attribute caching: FUSE can cache filesystem attributes for + * short periods of time (configurable via -o attr_timeout). It + * doesn't cache xattrs, and in any case FUSE caching doesn't solve + * the problem that we have to make a series of guestfs_lstat and + * guestfs_lgetxattr calls when we first list a directory (thus, many + * round trips). + * + * For this reason, we also implement a readdir cache here which is + * invoked when a readdir call is made. readdir is modified so that + * as well as reading the directory, it also requests all the stat + * structures, xattrs and readlinks of all entries in the directory, + * and these are added to the cache here (for a short, configurable + * period of time) in anticipation that they will be needed + * immediately afterwards, which is usually the case when the user is + * doing an "ls"-like operation. + * + * You can still use FUSE attribute caching on top of this mechanism + * if you like. + */ + +struct lsc_entry { /* lstat cache entry */ + char *pathname; /* full path to the file */ + time_t timeout; /* when this entry expires */ + struct stat statbuf; /* statbuf */ +}; + +struct xac_entry { /* xattr cache entry */ + /* NB first two fields must be same as lsc_entry */ + char *pathname; /* full path to the file */ + time_t timeout; /* when this entry expires */ + struct guestfs_xattr_list *xattrs; +}; + +struct rlc_entry { /* readlink cache entry */ + /* NB first two fields must be same as lsc_entry */ + char *pathname; /* full path to the file */ + time_t timeout; /* when this entry expires */ + char *link; +}; + +static size_t +gen_hash (void const *x, size_t table_size) +{ + struct lsc_entry const *p = x; + return hash_pjw (p->pathname, table_size); +} + +static bool +gen_compare (void const *x, void const *y) +{ + struct lsc_entry const *a = x; + struct lsc_entry const *b = y; + return STREQ (a->pathname, b->pathname); +} + +static void +lsc_free (void *x) +{ + if (x) { + struct lsc_entry *p = x; + + free (p->pathname); + free (p); + } +} + +static void +xac_free (void *x) +{ + if (x) { + struct xac_entry *p = x; + + guestfs_free_xattr_list (p->xattrs); + lsc_free (x); + } +} + +static void +rlc_free (void *x) +{ + if (x) { + struct rlc_entry *p = x; + + free (p->link); + lsc_free (x); + } +} + +static int +init_dir_caches (guestfs_h *g) +{ + g->lsc_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, lsc_free); + g->xac_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, xac_free); + g->rlc_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, rlc_free); + if (!g->lsc_ht || !g->xac_ht || !g->rlc_ht) { + error (g, _("could not initialize dir cache hashtables")); + return -1; + } + return 0; +} + +static void +free_dir_caches (guestfs_h *g) +{ + hash_free (g->lsc_ht); + hash_free (g->xac_ht); + hash_free (g->rlc_ht); +} + +struct gen_remove_data { + time_t now; + Hash_table *ht; + Hash_data_freer freer; +}; + +static bool +gen_remove_if_expired (void *x, void *data) +{ + /* XXX hash_do_for_each was observed calling this function + * with x == NULL. + */ + if (x) { + struct lsc_entry *p = x; + struct gen_remove_data *d = data; + + if (p->timeout < d->now) + d->freer (hash_delete (d->ht, x)); + } + + return 1; +} + +static void +gen_remove_all_expired (Hash_table *ht, Hash_data_freer freer, time_t now) +{ + struct gen_remove_data data; + data.now = now; + data.ht = ht; + data.freer = freer; + + /* Careful reading of the documentation to hash _seems_ to indicate + * that this is safe, _provided_ we use the default thresholds (in + * particular, no shrink threshold). + */ + hash_do_for_each (ht, gen_remove_if_expired, &data); +} + +static void +dir_cache_remove_all_expired (guestfs_h *g, time_t now) +{ + gen_remove_all_expired (g->lsc_ht, lsc_free, now); + gen_remove_all_expired (g->xac_ht, xac_free, now); + gen_remove_all_expired (g->rlc_ht, rlc_free, now); +} + +static int +gen_replace (Hash_table *ht, struct lsc_entry *new_entry, Hash_data_freer freer) +{ + struct lsc_entry *old_entry; + + old_entry = hash_delete (ht, new_entry); + freer (old_entry); + + old_entry = hash_insert (ht, new_entry); + if (old_entry == NULL) { + perror ("hash_insert"); + freer (new_entry); + return -1; + } + /* assert (old_entry == new_entry); */ + + return 0; +} + +static int +lsc_insert (guestfs_h *g, + const char *path, const char *name, time_t now, + struct stat const *statbuf) +{ + struct lsc_entry *entry; + + entry = malloc (sizeof *entry); + if (entry == NULL) { + perror ("malloc"); + return -1; + } + + size_t len = strlen (path) + strlen (name) + 2; + entry->pathname = malloc (len); + if (entry->pathname == NULL) { + perror ("malloc"); + free (entry); + return -1; + } + if (STREQ (path, "/")) + snprintf (entry->pathname, len, "/%s", name); + else + snprintf (entry->pathname, len, "%s/%s", path, name); + + memcpy (&entry->statbuf, statbuf, sizeof entry->statbuf); + + entry->timeout = now + g->dir_cache_timeout; + + return gen_replace (g->lsc_ht, entry, lsc_free); +} + +static int +xac_insert (guestfs_h *g, + const char *path, const char *name, time_t now, + struct guestfs_xattr_list *xattrs) +{ + struct xac_entry *entry; + + entry = malloc (sizeof *entry); + if (entry == NULL) { + perror ("malloc"); + return -1; + } + + size_t len = strlen (path) + strlen (name) + 2; + entry->pathname = malloc (len); + if (entry->pathname == NULL) { + perror ("malloc"); + free (entry); + return -1; + } + if (STREQ (path, "/")) + snprintf (entry->pathname, len, "/%s", name); + else + snprintf (entry->pathname, len, "%s/%s", path, name); + + entry->xattrs = xattrs; + + entry->timeout = now + g->dir_cache_timeout; + + return gen_replace (g->xac_ht, (struct lsc_entry *) entry, xac_free); +} + +static int +rlc_insert (guestfs_h *g, + const char *path, const char *name, time_t now, + char *link) +{ + struct rlc_entry *entry; + + entry = malloc (sizeof *entry); + if (entry == NULL) { + perror ("malloc"); + return -1; + } + + size_t len = strlen (path) + strlen (name) + 2; + entry->pathname = malloc (len); + if (entry->pathname == NULL) { + perror ("malloc"); + free (entry); + return -1; + } + if (STREQ (path, "/")) + snprintf (entry->pathname, len, "/%s", name); + else + snprintf (entry->pathname, len, "%s/%s", path, name); + + entry->link = link; + + entry->timeout = now + g->dir_cache_timeout; + + return gen_replace (g->rlc_ht, (struct lsc_entry *) entry, rlc_free); +} + +static const struct stat * +lsc_lookup (guestfs_h *g, const char *pathname) +{ + const struct lsc_entry key = { .pathname = (char *) pathname }; + struct lsc_entry *entry; + time_t now; + + time (&now); + + entry = hash_lookup (g->lsc_ht, &key); + if (entry && entry->timeout >= now) + return &entry->statbuf; + else + return NULL; +} + +static const struct guestfs_xattr_list * +xac_lookup (guestfs_h *g, const char *pathname) +{ + const struct xac_entry key = { .pathname = (char *) pathname }; + struct xac_entry *entry; + time_t now; + + time (&now); + + entry = hash_lookup (g->xac_ht, &key); + if (entry && entry->timeout >= now) + return entry->xattrs; + else + return NULL; +} + +static const char * +rlc_lookup (guestfs_h *g, const char *pathname) +{ + const struct rlc_entry key = { .pathname = (char *) pathname }; + struct rlc_entry *entry; + time_t now; + + time (&now); + + entry = hash_lookup (g->rlc_ht, &key); + if (entry && entry->timeout >= now) + return entry->link; + else + return NULL; +} + +static void +lsc_remove (Hash_table *ht, const char *pathname, Hash_data_freer freer) +{ + const struct lsc_entry key = { .pathname = (char *) pathname }; + struct lsc_entry *entry; + + entry = hash_delete (ht, &key); + + freer (entry); +} + +static void +dir_cache_invalidate (guestfs_h *g, const char *path) +{ + lsc_remove (g->lsc_ht, path, lsc_free); + lsc_remove (g->xac_ht, path, xac_free); + lsc_remove (g->rlc_ht, path, rlc_free); +} + +#else /* !HAVE_FUSE */ + +int +guestfs__mount_local (guestfs_h *g, const char *localmountpoint, + const struct guestfs_mount_local_argv *optargs) +{ + guestfs_error_errno (g, ENOTSUP, _("FUSE not supported")); + return -1; +} + +int +guestfs__umount_local (guestfs_h *g, + const struct guestfs_umount_local_argv *optargs) +{ + guestfs_error_errno (g, ENOTSUP, _("FUSE not supported")); + return -1; +} + +#endif /* !HAVE_FUSE */ diff --git a/src/guestfs-internal.h b/src/guestfs-internal.h index 1943f1a..5ea9e38 100644 --- a/src/guestfs-internal.h +++ b/src/guestfs-internal.h @@ -24,6 +24,8 @@ #include <pcre.h> +#include "hash.h" + #ifndef O_CLOEXEC #define O_CLOEXEC 0 #endif @@ -248,6 +250,13 @@ struct guestfs_h * matter for this case because we only care if it is != 0. */ int user_cancel; + + /* These fields are used by guestfs_mount_local. Only valid when + * g->localmountpoint is not NULL. + */ + const char *localmountpoint; + int dir_cache_timeout; + Hash_table *lsc_ht, *xac_ht, *rlc_ht; }; /* Per-filesystem data stored for inspect_os. */ diff --git a/src/guestfs.pod b/src/guestfs.pod index 531d123..ea2e383 100644 --- a/src/guestfs.pod +++ b/src/guestfs.pod @@ -1926,6 +1926,23 @@ do not generate this event. If no callback is registered: the event is ignored. +=item GUESTFS_EVENT_MOUNTED +(payload type: mountpoint) + +This callback function is called when L</guestfs_mount_local> +completes the initial processing for mounting the libguestfs +filesystem on a local directory (the mountpoint). + +Processing of filesystem requests does not start until the +callback returns, so the callback should not do any long-running +operations. B<Doing so will result in the process deadlocking>. +Forking a background process, starting a thread, or waiting +briefly for a thread barrier would all be fine. + +The callback must not attempt to access the mountpoint directory +(except if it launches another thread or process to do so +asynchronously). + =back =head3 guestfs_set_event_callback -- 1.7.9.3
Richard W.M. Jones
2012-Mar-27 15:27 UTC
[Libguestfs] [PATCH 3/3] Add test of parallel mount-local calls.
From: "Richard W.M. Jones" <rjones at redhat.com> --- .gitignore | 2 + ocaml/Makefile.am | 25 ++++- ocaml/t/exit.c | 44 ++++++++ ocaml/t/guestfs_500_parallel_mount_local.ml | 146 +++++++++++++++++++++++++++ po/POTFILES.in | 1 + 5 files changed, 216 insertions(+), 2 deletions(-) create mode 100644 ocaml/t/exit.c create mode 100644 ocaml/t/guestfs_500_parallel_mount_local.ml diff --git a/.gitignore b/.gitignore index b278ce2..f365a71 100644 --- a/.gitignore +++ b/.gitignore @@ -236,6 +236,8 @@ ocaml/t/guestfs_400_events.bc ocaml/t/guestfs_400_events.opt ocaml/t/guestfs_400_progress.bc ocaml/t/guestfs_400_progress.opt +ocaml/t/guestfs_500_parallel_mount_local.bc +ocaml/t/guestfs_500_parallel_mount_local.opt *.orig *.patch perl/bindtests.pl diff --git a/ocaml/Makefile.am b/ocaml/Makefile.am index c313532..8c742a2 100644 --- a/ocaml/Makefile.am +++ b/ocaml/Makefile.am @@ -30,6 +30,7 @@ EXTRA_DIST = \ html/.gitignore \ META.in \ run-bindtests \ + t/exit.c \ t/*.ml CLEANFILES = *.cmi *.cmo *.cmx *.cma *.cmxa *.o *.a *.so @@ -87,7 +88,8 @@ if ENABLE_APPLIANCE test_progs += \ t/guestfs_010_basic \ t/guestfs_070_threads \ - t/guestfs_400_progress + t/guestfs_400_progress \ + t/guestfs_500_parallel_mount_local endif TESTS = run-bindtests \ @@ -163,13 +165,32 @@ t/guestfs_400_progress.opt: t/guestfs_400_progress.cmx mlguestfs.cmxa mkdir -p t $(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) -cclib -L$(top_builddir)/src/.libs -I . -package unix -linkpkg mlguestfs.cmxa $< -o $@ -# Explicit rules for this test which requires 'threads' package. +t/guestfs_500_parallel_mount_local.bc: t/guestfs_500_parallel_mount_local.cmo mlguestfs.cma libocamltestlib.a + mkdir -p t + LD_LIBRARY_PATH=../src/.libs \ + $(OCAMLFIND) ocamlc -custom $(OCAMLCFLAGS) -I . -package unix,threads -thread -linkpkg mlguestfs.cma libocamltestlib.a $< -o $@ + +t/guestfs_500_parallel_mount_local.opt: t/guestfs_500_parallel_mount_local.cmx mlguestfs.cmxa libocamltestlib.a + mkdir -p t + $(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) -cclib -L$(top_builddir)/src/.libs -I . -package unix,threads -thread -linkpkg mlguestfs.cmxa libocamltestlib.a $< -o $@ + +# Explicit rules for these tests which require 'threads' package. t/guestfs_070_threads.cmo: t/guestfs_070_threads.ml mlguestfs.cma $(OCAMLFIND) ocamlc $(OCAMLCFLAGS) -package unix,threads -thread -linkpkg -c $< -o $@ t/guestfs_070_threads.cmx: t/guestfs_070_threads.ml mlguestfs.cmxa $(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) -package unix,threads -thread -linkpkg -c $< -o $@ +t/guestfs_500_parallel_mount_local.cmo: t/guestfs_500_parallel_mount_local.ml mlguestfs.cma + $(OCAMLFIND) ocamlc $(OCAMLCFLAGS) -package unix,threads -thread -linkpkg -c $< -o $@ + +t/guestfs_500_parallel_mount_local.cmx: t/guestfs_500_parallel_mount_local.ml mlguestfs.cmxa + $(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) -package unix,threads -thread -linkpkg -c $< -o $@ + +noinst_LIBRARIES += libocamltestlib.a +libocamltestlib_a_SOURCES = t/exit.c +libocamltestlib_a_CFLAGS = $(libguestfsocaml_a_CFLAGS) + %.cmi: %.mli $(OCAMLFIND) ocamlc $(OCAMLCFLAGS) -package unix -c $< -o $(builddir)/$@ %.cmo: %.ml mlguestfs.cma diff --git a/ocaml/t/exit.c b/ocaml/t/exit.c new file mode 100644 index 0000000..ca392de --- /dev/null +++ b/ocaml/t/exit.c @@ -0,0 +1,44 @@ +/* libguestfs OCaml bindings + * Copyright (C) 2012 Red Hat Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include <caml/alloc.h> +#include <caml/fail.h> +#include <caml/memory.h> +#include <caml/misc.h> +#include <caml/mlvalues.h> + +value ocaml_guestfs__exit (value) Noreturn; + +/* _exit : int -> 'a (does not return) */ +value +ocaml_guestfs__exit (value statusv) +{ + CAMLparam1 (statusv); + int status = Int_val (statusv); + + _exit (status); + + /*NOTREACHED*/ + CAMLnoreturn; +} diff --git a/ocaml/t/guestfs_500_parallel_mount_local.ml b/ocaml/t/guestfs_500_parallel_mount_local.ml new file mode 100644 index 0000000..0ea5338 --- /dev/null +++ b/ocaml/t/guestfs_500_parallel_mount_local.ml @@ -0,0 +1,146 @@ +(* libguestfs OCaml bindings + * Copyright (C) 2012 Red Hat Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + *) + +(* Test guestfs_mount_local, from a higher level language (it will + * mostly be used first from Python), in parallel threads. OCaml + * allows us to test this at a reasonable speed. + *) + +open Unix +open Printf + +let (//) = Filename.concat + +(* See [exit.c]. *) +external _exit : int -> 'a = "ocaml_guestfs__exit" + +let nr_threads = 5 +let total_time = 60. (* seconds, excluding launch *) +let debug = true (* overview debugging messages *) + +let rec main () + Random.self_init (); + + let threads = ref [] in + for i = 1 to nr_threads do + let filename = sprintf "test%d.img" i in + let mp = sprintf "mp%d" i in + (try rmdir mp with Unix_error _ -> ()); + mkdir mp 0o700; + let t = Thread.create start_thread (filename, mp) in + threads := (t, filename, mp) :: !threads + done; + + (* Wait until the threads terminate and delete the files and mountpoints. *) + List.iter ( + fun (t, filename, mp) -> + Thread.join t; + unlink filename; + rmdir mp + ) !threads; + + Gc.compact () + +and start_thread (filename, mp) + (* Create a filesystem for the tests. *) + let g = new Guestfs.guestfs () in + + let fd = openfile filename [O_WRONLY;O_CREAT;O_NOCTTY;O_TRUNC] 0o666 in + ftruncate fd (500 * 1024 * 1024); + close fd; + + g#add_drive_opts filename; + g#launch (); + + g#part_disk "/dev/sda" "mbr"; + g#mkfs "ext2" "/dev/sda1"; + g#mount "/dev/sda1" "/"; + + let test_pid = ref 0 in + ignore (g#set_event_callback (mounted test_pid) [Guestfs.EVENT_MOUNTED]); + + (* Randomly mount the filesystem and repeat. Keep going until we + * finish the test. The interesting stuff is happening in the + * 'mounted' event callback. + *) + let start_t = time () in + let rec loop () + let t = time () in + if t -. start_t < total_time then ( + if debug then eprintf "%s < mounting filesystem\n%!" mp; + test_pid := 0; + g#mount_local mp; + assert (!test_pid <> 0); (* mounted callback should have been called *) + let _, status = waitpid [] !test_pid in + (match status with + | WEXITED 0 -> () + | WEXITED i -> + eprintf "test subprocess failed (exit code %d)\n" i; + exit 1 + | WSIGNALED i | WSTOPPED i -> + eprintf "test subprocess signaled/stopped (signal %d)\n" i; + exit 1 + ); + loop () + ) + in + loop (); + + g#close () + +(* This callback is called when the filesystem at 'mp' is mounted and + * ready to use. We cannot run tests directly here, but must run them + * from another thread or process. We also must not perform any + * actions on the handle, except for the final call to + * umount_local. + *) +and mounted return_pid g _ _ mp _ + (* Run a subprocess to do the tests so we maximize parallelism + * across cores. + *) + let pid = fork () in + if pid = 0 (* child *) then test_mountpoint g mp; + return_pid := pid + +and test_mountpoint g mp + if debug then eprintf "%s | testing filesystem\n%!" mp; + + (* Run through the same set of tests repeatedly a number of times. + * The aim of this stress test is repeated mount/unmount, not testing + * FUSE itself, so we don't do much here. + *) + for pass = 0 to Random.int 32 do + mkdir (mp // "tmp.d") 0o700; + let chan = open_out (mp // "file") in + let s = String.create (Random.int (128 * 1024)) in + output_string chan s; + close_out chan; + rename (mp // "tmp.d") (mp // "newdir"); + link (mp // "file") (mp // "newfile"); + if Random.int 32 = 0 then sleep 1; + rmdir (mp // "newdir"); + unlink (mp // "file"); + unlink (mp // "newfile") + done; + + if debug then eprintf "%s > unmounting filesystem\n%!" mp; + Guestfs.umount_local ~retry:true g; + _exit 0 + +let () + main () diff --git a/po/POTFILES.in b/po/POTFILES.in index 1f0bb36..5df8b93 100644 --- a/po/POTFILES.in +++ b/po/POTFILES.in @@ -135,6 +135,7 @@ inspector/virt-inspector.c java/com_redhat_et_libguestfs_GuestFS.c ocaml/guestfs_c.c ocaml/guestfs_c_actions.c +ocaml/t/exit.c perl/Guestfs.c perl/bindtests.pl perl/lib/Sys/Guestfs.pm -- 1.7.9.3
Possibly Parallel Threads
- [PATCH v2] New APIs: mount-local and umount-local using FUSE
- [PATCH v3] New APIs: mount-local, mount-local-run and umount-local using FUSE
- [PATCH] fuse: provide a stub "flush" implementation (RHBZ#660687).
- [PATCH] fuse: clear stat structs (RHBZ#660687).
- [PATCH 0/5] Four fixes for FUSE support and a test script