From 1ab9ed2afb7ca50c4f922a0b85c4e6631becde02 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 27 Mar 2017 14:36:56 +1100 Subject: [PATCH] Add 'force' flag to *hot_remove_disk(). In rare circumstances, the short period that *hot_remove_disk() waits isn't long enough to IO to complete. This particularly happens when a device is failing and many retries are still happening. We don't want to increase the normal wait time for "mdadm --remove" as that might be use just to test if a device is active or not, and a delay would be problematic. So allow "--force" to mean that mdadm should try extra hard for a --remove to complete, waiting up to 5 seconds. Note that this patch fixes a comment which claim the previous wait time was half a second, where it was really 50msec. Signed-off-by: NeilBrown Signed-off-by: Jes Sorensen --- Grow.c | 2 +- Manage.c | 10 +++++----- mdadm.h | 4 ++-- util.c | 10 +++++----- 4 files changed, 13 insertions(+), 13 deletions(-) diff --git a/Grow.c b/Grow.c index 218a7064..e22661ca 100755 --- a/Grow.c +++ b/Grow.c @@ -2749,7 +2749,7 @@ static int impose_level(int fd, int level, char *devname, int verbose) continue; ioctl(fd, SET_DISK_FAULTY, makedev(disk.major, disk.minor)); - hot_remove_disk(fd, makedev(disk.major, disk.minor)); + hot_remove_disk(fd, makedev(disk.major, disk.minor), 1); } } c = map_num(pers, level); diff --git a/Manage.c b/Manage.c index edf5798a..55218d9b 100644 --- a/Manage.c +++ b/Manage.c @@ -1110,7 +1110,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv, } int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv, - int sysfd, unsigned long rdev, int verbose, char *devname) + int sysfd, unsigned long rdev, int force, int verbose, char *devname) { int lfd = -1; int err; @@ -1177,9 +1177,9 @@ int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv, /* device has been removed and we don't know * the major:minor number */ - err = sys_hot_remove_disk(sysfd); + err = sys_hot_remove_disk(sysfd, force); } else { - err = hot_remove_disk(fd, rdev); + err = hot_remove_disk(fd, rdev, force); if (err && errno == ENODEV) { /* Old kernels rejected this if no personality * is registered */ @@ -1603,7 +1603,7 @@ int Manage_subdevs(char *devname, int fd, if (dv->disposition == 'F') /* Need to remove first */ - hot_remove_disk(fd, rdev); + hot_remove_disk(fd, rdev, force); /* Make sure it isn't in use (in 2.6 or later) */ tfd = dev_open(dv->devname, O_RDONLY|O_EXCL); if (tfd >= 0) { @@ -1645,7 +1645,7 @@ int Manage_subdevs(char *devname, int fd, rv = -1; } else rv = Manage_remove(tst, fd, dv, sysfd, - rdev, verbose, + rdev, verbose, force, devname); if (sysfd >= 0) close(sysfd); diff --git a/mdadm.h b/mdadm.h index b855d242..cebc0c0a 100644 --- a/mdadm.h +++ b/mdadm.h @@ -1476,8 +1476,8 @@ extern int add_disk(int mdfd, struct supertype *st, struct mdinfo *sra, struct mdinfo *info); extern int remove_disk(int mdfd, struct supertype *st, struct mdinfo *sra, struct mdinfo *info); -extern int hot_remove_disk(int mdfd, unsigned long dev); -extern int sys_hot_remove_disk(int statefd); +extern int hot_remove_disk(int mdfd, unsigned long dev, int force); +extern int sys_hot_remove_disk(int statefd, int force); extern int set_array_info(int mdfd, struct supertype *st, struct mdinfo *info); unsigned long long min_recovery_start(struct mdinfo *array); diff --git a/util.c b/util.c index b7185316..683c869a 100644 --- a/util.c +++ b/util.c @@ -1795,15 +1795,15 @@ int remove_disk(int mdfd, struct supertype *st, return rv; } -int hot_remove_disk(int mdfd, unsigned long dev) +int hot_remove_disk(int mdfd, unsigned long dev, int force) { - int cnt = 5; + int cnt = force ? 500 : 5; int ret; /* HOT_REMOVE_DISK can fail with EBUSY if there are * outstanding IO requests to the device. * In this case, it can be helpful to wait a little while, - * up to half a second, for that IO to flush. + * up to 5 seconds if 'force' is set, or 50 msec if not. */ while ((ret = ioctl(mdfd, HOT_REMOVE_DISK, dev)) == -1 && errno == EBUSY && @@ -1813,9 +1813,9 @@ int hot_remove_disk(int mdfd, unsigned long dev) return ret; } -int sys_hot_remove_disk(int statefd) +int sys_hot_remove_disk(int statefd, int force) { - int cnt = 5; + int cnt = force ? 500 : 5; int ret; while ((ret = write(statefd, "remove", 6)) == -1 && -- 2.39.2