diff options
| -rw-r--r-- | include/sys/fs/zfs.h | 1 | ||||
| -rw-r--r-- | lib/libzfs/os/linux/libzfs_util_os.c | 151 | ||||
| -rw-r--r-- | man/man8/zfs.8 | 20 | ||||
| -rw-r--r-- | man/man8/zpool.8 | 14 |
4 files changed, 103 insertions, 83 deletions
diff --git a/include/sys/fs/zfs.h b/include/sys/fs/zfs.h index f9fd5cf67..9cd1e32cd 100644 --- a/include/sys/fs/zfs.h +++ b/include/sys/fs/zfs.h @@ -1292,6 +1292,7 @@ typedef struct ddt_histogram { #define ZVOL_DRIVER "zvol" #define ZFS_DRIVER "zfs" #define ZFS_DEV "/dev/zfs" +#define ZFS_DEVDIR "/dev" #define ZFS_SUPER_MAGIC 0x2fc12fc1 diff --git a/lib/libzfs/os/linux/libzfs_util_os.c b/lib/libzfs/os/linux/libzfs_util_os.c index a32aa1513..c1443fda6 100644 --- a/lib/libzfs/os/linux/libzfs_util_os.c +++ b/lib/libzfs/os/linux/libzfs_util_os.c @@ -20,20 +20,24 @@ */ +#include <alloca.h> #include <errno.h> #include <fcntl.h> #include <libintl.h> +#include <math.h> +#include <poll.h> #include <stdarg.h> #include <stdio.h> #include <stdlib.h> #include <strings.h> -#include <unistd.h> -#include <math.h> -#include <sys/stat.h> -#include <sys/mnttab.h> +#include <sys/inotify.h> #include <sys/mntent.h> +#include <sys/mnttab.h> +#include <sys/stat.h> +#include <sys/timerfd.h> #include <sys/types.h> #include <sys/wait.h> +#include <unistd.h> #include <libzfs.h> #include <libzfs_core.h> @@ -57,7 +61,7 @@ libzfs_error_init(int error) switch (error) { case ENXIO: return (dgettext(TEXT_DOMAIN, "The ZFS modules are not " - "loaded.\nTry running '/sbin/modprobe zfs' as root " + "loaded.\nTry running 'modprobe zfs' as root " "to load them.")); case ENOENT: return (dgettext(TEXT_DOMAIN, "/dev/zfs and /proc/self/mounts " @@ -65,7 +69,7 @@ libzfs_error_init(int error) "-t proc proc /proc' as root.")); case ENOEXEC: return (dgettext(TEXT_DOMAIN, "The ZFS modules cannot be " - "auto-loaded.\nTry running '/sbin/modprobe zfs' as " + "auto-loaded.\nTry running 'modprobe zfs' as " "root to manually load them.")); case EACCES: return (dgettext(TEXT_DOMAIN, "Permission denied the " @@ -76,93 +80,80 @@ libzfs_error_init(int error) } } -static int -libzfs_module_loaded(const char *module) -{ - const char path_prefix[] = "/sys/module/"; - char path[256]; - - memcpy(path, path_prefix, sizeof (path_prefix) - 1); - strcpy(path + sizeof (path_prefix) - 1, module); - - return (access(path, F_OK) == 0); -} - /* - * Verify the required ZFS_DEV device is available and optionally attempt - * to load the ZFS modules. Under normal circumstances the modules - * should already have been loaded by some external mechanism. + * zfs(4) is loaded by udev if there's a fstype=zfs device present, + * but if there isn't, load them automatically; + * always wait for ZFS_DEV to appear via udev. * * Environment variables: - * - ZFS_MODULE_LOADING="YES|yes|ON|on" - Attempt to load modules. - * - ZFS_MODULE_TIMEOUT="<seconds>" - Seconds to wait for ZFS_DEV + * - ZFS_MODULE_TIMEOUT="<seconds>" - Seconds to wait for ZFS_DEV, + * defaults to 10, max. 10 min. */ -static int -libzfs_load_module_impl(const char *module) +int +libzfs_load_module(void) { - char *argv[4] = {"/sbin/modprobe", "-q", (char *)module, (char *)0}; - char *load_str, *timeout_str; - long timeout = 10; /* seconds */ - long busy_timeout = 10; /* milliseconds */ - int load = 0, fd; - hrtime_t start; - - /* Optionally request module loading */ - if (!libzfs_module_loaded(module)) { - load_str = getenv("ZFS_MODULE_LOADING"); - if (load_str) { - if (!strncasecmp(load_str, "YES", strlen("YES")) || - !strncasecmp(load_str, "ON", strlen("ON"))) - load = 1; - else - load = 0; - } + if (access(ZFS_DEV, F_OK) == 0) + return (0); - if (load) { - if (libzfs_run_process("/sbin/modprobe", argv, 0)) - return (ENOEXEC); - } + if (access(ZFS_SYSFS_DIR, F_OK) != 0) { + char *argv[] = {"modprobe", "zfs", NULL}; + if (libzfs_run_process("modprobe", argv, 0)) + return (ENOEXEC); - if (!libzfs_module_loaded(module)) + if (access(ZFS_SYSFS_DIR, F_OK) != 0) return (ENXIO); } - /* - * Device creation by udev is asynchronous and waiting may be - * required. Busy wait for 10ms and then fall back to polling every - * 10ms for the allowed timeout (default 10s, max 10m). This is - * done to optimize for the common case where the device is - * immediately available and to avoid penalizing the possible - * case where udev is slow or unable to create the device. - */ - timeout_str = getenv("ZFS_MODULE_TIMEOUT"); - if (timeout_str) { - timeout = strtol(timeout_str, NULL, 0); - timeout = MAX(MIN(timeout, (10 * 60)), 0); /* 0 <= N <= 600 */ + const char *timeout_str = getenv("ZFS_MODULE_TIMEOUT"); + int seconds = 10; + if (timeout_str) + seconds = MIN(strtol(timeout_str, NULL, 0), 600); + struct itimerspec timeout = {.it_value.tv_sec = MAX(seconds, 0)}; + + int ino = inotify_init1(IN_CLOEXEC); + if (ino == -1) + return (ENOENT); + inotify_add_watch(ino, ZFS_DEVDIR, IN_CREATE); + + if (access(ZFS_DEV, F_OK) == 0) { + close(ino); + return (0); + } else if (seconds == 0) { + close(ino); + return (ENOENT); } - start = gethrtime(); - do { - fd = open(ZFS_DEV, O_RDWR | O_CLOEXEC); - if (fd >= 0) { - (void) close(fd); - return (0); - } else if (errno != ENOENT) { - return (errno); - } else if (NSEC2MSEC(gethrtime() - start) < busy_timeout) { - sched_yield(); - } else { - usleep(10 * MILLISEC); - } - } while (NSEC2MSEC(gethrtime() - start) < (timeout * MILLISEC)); - - return (ENOENT); -} + size_t evsz = sizeof (struct inotify_event) + NAME_MAX + 1; + struct inotify_event *ev = alloca(evsz); -int -libzfs_load_module(void) -{ - return (libzfs_load_module_impl(ZFS_DRIVER)); + int tout = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC); + if (tout == -1) { + close(ino); + return (ENOENT); + } + timerfd_settime(tout, 0, &timeout, NULL); + + int ret = ENOENT; + struct pollfd pfds[] = { + {.fd = ino, .events = POLLIN}, + {.fd = tout, .events = POLLIN}, + }; + while (poll(pfds, ARRAY_SIZE(pfds), -1) != -1) { + if (pfds[0].revents & POLLIN) { + verify(read(ino, ev, evsz) > + sizeof (struct inotify_event)); + if (strcmp(ev->name, &ZFS_DEV[sizeof (ZFS_DEVDIR)]) + == 0) { + ret = 0; + break; + } + } + if (pfds[1].revents & POLLIN) + break; + } + close(tout); + close(ino); + return (ret); } int diff --git a/man/man8/zfs.8 b/man/man8/zfs.8 index cac4327e0..eaa93e0ea 100644 --- a/man/man8/zfs.8 +++ b/man/man8/zfs.8 @@ -736,7 +736,7 @@ Do note that any changes done with the command will be undone if the share is ever unshared (like via a reboot). . .Sh ENVIRONMENT VARIABLES -.Bl -tag -width "ZFS_MOUNT_HELPER" +.Bl -tag -width "ZFS_MODULE_TIMEOUT" .It Sy ZFS_MOUNT_HELPER Cause .Nm zfs Cm mount @@ -744,14 +744,28 @@ to use .Xr mount 8 to mount ZFS datasets. This option is provided for backwards compatibility with older ZFS versions. -.El -.Bl -tag -width "ZFS_SET_PIPE_MAX" +. .It Sy ZFS_SET_PIPE_MAX Tells .Nm zfs to set the maximum pipe size for sends/recieves. Disabled by default on Linux due to an unfixed deadlock in Linux's pipe size handling code. +. +.\" Shared with zpool.8 +.It Sy ZFS_MODULE_TIMEOUT +Time, in seconds, to wait for +.Pa /dev/zfs +to appear. +Defaults to +.Sy 10 , +max +.Sy 600 Pq 10 minutes . +If +.Pf < Sy 0 , +wait forever; if +.Sy 0 , +don't wait. .El . .Sh INTERFACE STABILITY diff --git a/man/man8/zpool.8 b/man/man8/zpool.8 index 34c816bf0..075e31bbe 100644 --- a/man/man8/zpool.8 +++ b/man/man8/zpool.8 @@ -524,6 +524,20 @@ If .Sy ZPOOL_SCRIPTS_ENABLED is not set, it is assumed that the user is allowed to run .Nm zpool Cm status Ns / Ns Cm iostat Fl c . +.\" Shared with zfs.8 +.It Sy ZFS_MODULE_TIMEOUT +Time, in seconds, to wait for +.Pa /dev/zfs +to appear. +Defaults to +.Sy 10 , +max +.Sy 600 Pq 10 minutes . +If +.Pf < Sy 0 , +wait forever; if +.Sy 0 , +don't wait. .El . .Sh INTERFACE STABILITY |