ping
On 2023/4/23 9:30, Li Xiao Keng wrote:
> ping
>
> On 2023/4/17 22:01, Li Xiao Keng wrote:
>> When we add a new disk to a raid, it may return -EBUSY.
>>
>> The main process of --add:
>> 1. dev_open
>> 2. store_super1(st, di->fd) in write_init_super1
>> 3. fsync(di->fd) in write_init_super1
>> 4. close(di->fd)
>> 5. ioctl(ADD_NEW_DISK)
>>
>> However, there will be some udev(change) event after step4. Then
>> "/usr/sbin/mdadm --incremental ..." will be run, and the new disk
>> will be add to md device. After that, ioctl will return -EBUSY.
>>
>> Here we add map_lock before write_init_super in "mdadm --add"
>> to fix this race.
>>
>> Signed-off-by: Li Xiao Keng <lixiaokeng@xxxxxxxxxx>
>> Signed-off-by: Guanqin Miao <miaoguanqin@xxxxxxxxxx>
>> ---
>> Assemble.c | 5 ++++-
>> Manage.c | 25 +++++++++++++++++--------
>> 2 files changed, 21 insertions(+), 9 deletions(-)
>>
>> diff --git a/Assemble.c b/Assemble.c
>> index 49804941..086890ed 100644
>> --- a/Assemble.c
>> +++ b/Assemble.c
>> @@ -1479,8 +1479,11 @@ try_again:
>> * to our list. We flag them so that we don't try to re-add,
>> * but can remove if they turn out to not be wanted.
>> */
>> - if (map_lock(&map))
>> + if (map_lock(&map)) {
>> pr_err("failed to get exclusive lock on mapfile - continue anyway...\n");
>> + return 1;
>> + }
>> +
>> if (c->update == UOPT_UUID)
>> mp = NULL;
>> else
>> diff --git a/Manage.c b/Manage.c
>> index f54de7c6..6a101bae 100644
>> --- a/Manage.c
>> +++ b/Manage.c
>> @@ -703,6 +703,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> struct supertype *dev_st;
>> int j;
>> mdu_disk_info_t disc;
>> + struct map_ent *map = NULL;
>>
>> if (!get_dev_size(tfd, dv->devname, &ldsize)) {
>> if (dv->disposition == 'M')
>> @@ -900,6 +901,10 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> disc.raid_disk = 0;
>> }
>>
>> + if (map_lock(&map)) {
>> + pr_err("failed to get exclusive lock on mapfile when add disk\n");
>> + return -1;
>> + }
>> if (array->not_persistent==0) {
>> int dfd;
>> if (dv->disposition == 'j')
>> @@ -911,9 +916,9 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> dfd = dev_open(dv->devname, O_RDWR | O_EXCL|O_DIRECT);
>> if (tst->ss->add_to_super(tst, &disc, dfd,
>> dv->devname, INVALID_SECTORS))
>> - return -1;
>> + goto unlock;
>> if (tst->ss->write_init_super(tst))
>> - return -1;
>> + goto unlock;
>> } else if (dv->disposition == 'A') {
>> /* this had better be raid1.
>> * As we are "--re-add"ing we must find a spare slot
>> @@ -971,14 +976,14 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> pr_err("add failed for %s: could not get exclusive access to container\n",
>> dv->devname);
>> tst->ss->free_super(tst);
>> - return -1;
>> + goto unlock;
>> }
>>
>> /* Check if metadata handler is able to accept the drive */
>> if (!tst->ss->validate_geometry(tst, LEVEL_CONTAINER, 0, 1, NULL,
>> 0, 0, dv->devname, NULL, 0, 1)) {
>> close(container_fd);
>> - return -1;
>> + goto unlock;
>> }
>>
>> Kill(dv->devname, NULL, 0, -1, 0);
>> @@ -987,7 +992,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> dv->devname, INVALID_SECTORS)) {
>> close(dfd);
>> close(container_fd);
>> - return -1;
>> + goto unlock;
>> }
>> if (!mdmon_running(tst->container_devnm))
>> tst->ss->sync_metadata(tst);
>> @@ -998,7 +1003,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> dv->devname);
>> close(container_fd);
>> tst->ss->free_super(tst);
>> - return -1;
>> + goto unlock;
>> }
>> sra->array.level = LEVEL_CONTAINER;
>> /* Need to set data_offset and component_size */
>> @@ -1013,7 +1018,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> pr_err("add new device to external metadata failed for %s\n", dv->devname);
>> close(container_fd);
>> sysfs_free(sra);
>> - return -1;
>> + goto unlock;
>> }
>> ping_monitor(devnm);
>> sysfs_free(sra);
>> @@ -1027,7 +1032,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> else
>> pr_err("add new device failed for %s as %d: %s\n",
>> dv->devname, j, strerror(errno));
>> - return -1;
>> + goto unlock;
>> }
>> if (dv->disposition == 'j') {
>> pr_err("Journal added successfully, making %s read-write\n", devname);
>> @@ -1038,7 +1043,11 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
>> }
>> if (verbose >= 0)
>> pr_err("added %s\n", dv->devname);
>> + map_unlock(&map);
>> return 1;
>> +unlock:
>> + map_unlock(&map);
>> + return -1;
>> }
>>
>> int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv,
>>
