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author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
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committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /drivers/md/dm-snap-transient.c | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
download | FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2 FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip |
Moved, renamed, and deleted files
The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
Diffstat (limited to 'drivers/md/dm-snap-transient.c')
-rw-r--r-- | drivers/md/dm-snap-transient.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/drivers/md/dm-snap-transient.c b/drivers/md/dm-snap-transient.c new file mode 100644 index 00000000..1ce9a258 --- /dev/null +++ b/drivers/md/dm-snap-transient.c @@ -0,0 +1,153 @@ +/* + * 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 <linux/mm.h> +#include <linux/pagemap.h> +#include <linux/vmalloc.h> +#include <linux/export.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_dtr(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_exception *e) +{ + struct transient_c *tc = store->context; + sector_t size = get_dev_size(dm_snap_cow(store->snap)->bdev); + + if (size < (tc->next_free + store->chunk_size)) + return -1; + + e->new_chunk = sector_to_chunk(store, tc->next_free); + tc->next_free += store->chunk_size; + + return 0; +} + +static void transient_commit_exception(struct dm_exception_store *store, + struct dm_exception *e, + void (*callback) (void *, int success), + void *callback_context) +{ + /* Just succeed */ + callback(callback_context, 1); +} + +static void transient_usage(struct dm_exception_store *store, + sector_t *total_sectors, + sector_t *sectors_allocated, + sector_t *metadata_sectors) +{ + *sectors_allocated = ((struct transient_c *) store->context)->next_free; + *total_sectors = get_dev_size(dm_snap_cow(store->snap)->bdev); + *metadata_sectors = 0; +} + +static int transient_ctr(struct dm_exception_store *store, + unsigned argc, char **argv) +{ + struct transient_c *tc; + + tc = kmalloc(sizeof(struct transient_c), GFP_KERNEL); + if (!tc) + return -ENOMEM; + + tc->next_free = 0; + store->context = tc; + + return 0; +} + +static unsigned transient_status(struct dm_exception_store *store, + status_type_t status, char *result, + unsigned maxlen) +{ + unsigned sz = 0; + + switch (status) { + case STATUSTYPE_INFO: + break; + case STATUSTYPE_TABLE: + DMEMIT(" N %llu", (unsigned long long)store->chunk_size); + } + + return sz; +} + +static struct dm_exception_store_type _transient_type = { + .name = "transient", + .module = THIS_MODULE, + .ctr = transient_ctr, + .dtr = transient_dtr, + .read_metadata = transient_read_metadata, + .prepare_exception = transient_prepare_exception, + .commit_exception = transient_commit_exception, + .usage = transient_usage, + .status = transient_status, +}; + +static struct dm_exception_store_type _transient_compat_type = { + .name = "N", + .module = THIS_MODULE, + .ctr = transient_ctr, + .dtr = transient_dtr, + .read_metadata = transient_read_metadata, + .prepare_exception = transient_prepare_exception, + .commit_exception = transient_commit_exception, + .usage = transient_usage, + .status = transient_status, +}; + +int dm_transient_snapshot_init(void) +{ + int r; + + r = dm_exception_store_type_register(&_transient_type); + if (r) { + DMWARN("Unable to register transient exception store type"); + return r; + } + + r = dm_exception_store_type_register(&_transient_compat_type); + if (r) { + DMWARN("Unable to register old-style transient " + "exception store type"); + dm_exception_store_type_unregister(&_transient_type); + return r; + } + + return r; +} + +void dm_transient_snapshot_exit(void) +{ + dm_exception_store_type_unregister(&_transient_type); + dm_exception_store_type_unregister(&_transient_compat_type); +} |