dm ioctl: report event number in DM_LIST_DEVICES (23d70c5e) · Commits · 戴 / test

Report the event numbers for all the devices, so that the user doesn't have to ask them one by one. The event number is reported after the name field in the dm_name_list structure. The location of the next record is specified in the dm_name_list->next field, that means that we can put the new data after the end of name and it is backward compatible with the old code. The old code just skips the event number without interpreting it. Signed-off-by:

Mikulas Patocka <mpatocka@redhat.com> Signed-off-by:

Andy Grover <agrover@redhat.com> Signed-off-by:

Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-ioctl.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -506,6 +506,7 @@ static int list_devices(struct file filp, struct dm_ioctl param, size_t param_
		size_t len, needed = 0;
		struct gendisk *disk;
		struct dm_name_list nl, old_nl = NULL;
		uint32_t *event_nr;

		down_write(&_hash_lock);

		@@ -518,6 +519,7 @@ static int list_devices(struct file filp, struct dm_ioctl param, size_t param_
		needed += sizeof(struct dm_name_list);
		needed += strlen(hc->name) + 1;
		needed += ALIGN_MASK;
		needed += (sizeof(uint32_t) + ALIGN_MASK) & ~ALIGN_MASK;
		}
		}

		@@ -547,7 +549,9 @@ static int list_devices(struct file filp, struct dm_ioctl param, size_t param_
		strcpy(nl->name, hc->name);

		old_nl = nl;
		nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1);
		event_nr = align_ptr(((void *) (nl + 1)) + strlen(hc->name) + 1);
		*event_nr = dm_get_event_nr(hc->md);
		nl = align_ptr(event_nr + 1);
		}
		}

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