From 45194e4f89fbdd97a2b7d2698c05f0b00c19e820 Mon Sep 17 00:00:00 2001 From: Cheng Renquan Date: Thu, 2 Apr 2009 19:55:28 +0100 Subject: dm target: remove struct tt_internal The tt_internal is really just a list_head to manage registered target_type in a double linked list, Here embed the list_head into target_type directly, 1. to avoid kmalloc/kfree; 2. then tt_internal is really unneeded; Cc: stable@kernel.org Signed-off-by: Cheng Renquan Signed-off-by: Alasdair G Kergon Reviewed-by: Alasdair G Kergon --- include/linux/device-mapper.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 8209e08969f9..66ec05a57955 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -139,6 +139,9 @@ struct target_type { dm_ioctl_fn ioctl; dm_merge_fn merge; dm_busy_fn busy; + + /* For internal device-mapper use. */ + struct list_head list; }; struct io_restrictions { -- cgit v1.2.3 From ec44ab9d6681ddf9026b593e866bec9c0e075e1d Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Thu, 2 Apr 2009 19:55:30 +0100 Subject: dm log: remove struct dm_dirty_log_internal Remove the 'dm_dirty_log_internal' structure. The resulting cleanup eliminates extra memory allocations. Therefore exposing the internal list_head to the external 'dm_dirty_log_type' structure is a worthwhile compromise. Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- include/linux/dm-dirty-log.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/dm-dirty-log.h b/include/linux/dm-dirty-log.h index 600c5fb2daad..727602b686d4 100644 --- a/include/linux/dm-dirty-log.h +++ b/include/linux/dm-dirty-log.h @@ -28,6 +28,9 @@ struct dm_dirty_log_type { const char *name; struct module *module; + /* For internal device-mapper use */ + struct list_head list; + int (*ctr)(struct dm_dirty_log *log, struct dm_target *ti, unsigned argc, char **argv); void (*dtr)(struct dm_dirty_log *log); -- cgit v1.2.3 From 7513c2a761d69d2a93f17146b3563527d3618ba0 Mon Sep 17 00:00:00 2001 From: Jonathan Brassow Date: Thu, 2 Apr 2009 19:55:30 +0100 Subject: dm raid1: add is_remote_recovering hook for clusters The logging API needs an extra function to make cluster mirroring possible. This new function allows us to check whether a mirror region is being recovered on another machine in the cluster. This helps us prevent simultaneous recovery I/O and process I/O to the same locations on disk. Cluster-aware log modules will implement this function. Single machine log modules will not. So, there is no performance penalty for single machine mirrors. Signed-off-by: Jonathan Brassow Acked-by: Heinz Mauelshagen Signed-off-by: Alasdair G Kergon --- include/linux/dm-dirty-log.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include/linux') diff --git a/include/linux/dm-dirty-log.h b/include/linux/dm-dirty-log.h index 727602b686d4..5e8b11d88f6f 100644 --- a/include/linux/dm-dirty-log.h +++ b/include/linux/dm-dirty-log.h @@ -116,6 +116,16 @@ struct dm_dirty_log_type { */ int (*status)(struct dm_dirty_log *log, status_type_t status_type, char *result, unsigned maxlen); + + /* + * is_remote_recovering is necessary for cluster mirroring. It provides + * a way to detect recovery on another node, so we aren't writing + * concurrently. This function is likely to block (when a cluster log + * is used). + * + * Returns: 0, 1 + */ + int (*is_remote_recovering)(struct dm_dirty_log *log, region_t region); }; int dm_dirty_log_type_register(struct dm_dirty_log_type *type); -- cgit v1.2.3