diff options
author | Ingo Molnar <mingo@elte.hu> | 2009-01-18 18:37:14 +0100 |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-01-18 18:37:14 +0100 |
commit | b2b062b8163391c42b3219d466ca1ac9742b9c7b (patch) | |
tree | f3f920c09b8de694b1bc1d4b878cfd2b0b98c913 /drivers/md/dm-snap-transient.c | |
parent | a9de18eb761f7c1c860964b2e5addc1a35c7e861 (diff) | |
parent | 99937d6455cea95405ac681c86a857d0fcd530bd (diff) |
Merge branch 'core/percpu' into stackprotector
Conflicts:
arch/x86/include/asm/pda.h
arch/x86/include/asm/system.h
Also, moved include/asm-x86/stackprotector.h to arch/x86/include/asm.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'drivers/md/dm-snap-transient.c')
-rw-r--r-- | drivers/md/dm-snap-transient.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/md/dm-snap-transient.c b/drivers/md/dm-snap-transient.c new file mode 100644 index 000000000000..7f6e2e6dcb0d --- /dev/null +++ b/drivers/md/dm-snap-transient.c @@ -0,0 +1,98 @@ +/* + * Copyright (C) 2001-2002 Sistina Software (UK) Limited. + * Copyright (C) 2006-2008 Red Hat GmbH + * + * This file is released under the GPL. + */ + +#include "dm-exception-store.h" +#include "dm-snap.h" + +#include <linux/mm.h> +#include <linux/pagemap.h> +#include <linux/vmalloc.h> +#include <linux/slab.h> +#include <linux/dm-io.h> + +#define DM_MSG_PREFIX "transient snapshot" + +/*----------------------------------------------------------------- + * Implementation of the store for non-persistent snapshots. + *---------------------------------------------------------------*/ +struct transient_c { + sector_t next_free; +}; + +static void transient_destroy(struct dm_exception_store *store) +{ + kfree(store->context); +} + +static int transient_read_metadata(struct dm_exception_store *store, + int (*callback)(void *callback_context, + chunk_t old, chunk_t new), + void *callback_context) +{ + return 0; +} + +static int transient_prepare_exception(struct dm_exception_store *store, + struct dm_snap_exception *e) +{ + struct transient_c *tc = (struct transient_c *) store->context; + sector_t size = get_dev_size(store->snap->cow->bdev); + + if (size < (tc->next_free + store->snap->chunk_size)) + return -1; + + e->new_chunk = sector_to_chunk(store->snap, tc->next_free); + tc->next_free += store->snap->chunk_size; + + return 0; +} + +static void transient_commit_exception(struct dm_exception_store *store, + struct dm_snap_exception *e, + void (*callback) (void *, int success), + void *callback_context) +{ + /* Just succeed */ + callback(callback_context, 1); +} + +static void transient_fraction_full(struct dm_exception_store *store, + sector_t *numerator, sector_t *denominator) +{ + *numerator = ((struct transient_c *) store->context)->next_free; + *denominator = get_dev_size(store->snap->cow->bdev); +} + +int dm_create_transient(struct dm_exception_store *store) +{ + struct transient_c *tc; + + store->destroy = transient_destroy; + store->read_metadata = transient_read_metadata; + store->prepare_exception = transient_prepare_exception; + store->commit_exception = transient_commit_exception; + store->drop_snapshot = NULL; + store->fraction_full = transient_fraction_full; + + tc = kmalloc(sizeof(struct transient_c), GFP_KERNEL); + if (!tc) + return -ENOMEM; + + tc->next_free = 0; + store->context = tc; + + return 0; +} + +int dm_transient_snapshot_init(void) +{ + return 0; +} + +void dm_transient_snapshot_exit(void) +{ +} |