116 	void *area;  member
119 	 * An area of zeros used to clear the next area.
124 	 * An area used for header. The header can be written
131 	 * Used to keep track of which metadata area the data in
158 	 * metadata area.
179 	 * a single metadata area.  in alloc_area()
181 	ps->area = vmalloc(len);  in alloc_area()
182 	if (!ps->area)  in alloc_area()
199 	vfree(ps->area);  in alloc_area()
207 	vfree(ps->area);  in free_area()
208 	ps->area = NULL;  in free_area()
232 static int chunk_io(struct pstore *ps, void *area, chunk_t chunk, blk_opf_t opf,  in chunk_io()  argument
243 		.mem.ptr.vma = area,  in chunk_io()
268  * Convert a metadata area index to a chunk index.
270 static chunk_t area_location(struct pstore *ps, chunk_t area)  in area_location()  argument
272 	return NUM_SNAPSHOT_HDR_CHUNKS + ((ps->exceptions_per_area + 1) * area);  in area_location()
285  * Read or write a metadata area.  Remembering to skip the first
292 	return chunk_io(ps, ps->area, chunk, opf, 0);  in area_io()
297 	memset(ps->area, 0, ps->store->chunk_size << SECTOR_SHIFT);  in zero_memory_area()
300 static int zero_disk_area(struct pstore *ps, chunk_t area)  in zero_disk_area()  argument
302 	return chunk_io(ps, ps->zero_area, area_location(ps, area),  in zero_disk_area()
422 	struct disk_exception *de = get_exception(ps, ps->area, index);  in write_exception()
431 	struct disk_exception *de = get_exception(ps, ps->area, index);  in clear_exception()
439  * Registers the exceptions that are present in the current area.
440  * 'full' is filled in to indicate if the area has been
453 	/* presume the area is full */  in insert_exceptions()
461 		 * the COW device, where the first metadata area  in insert_exceptions()
463 		 * exceptions.  Therefore the area is not full.  in insert_exceptions()
511 	 * we find a partially full area.  in read_exceptions()
515 		void *area;  in read_exceptions()  local
536 		area = dm_bufio_read(client, chunk, &bp);  in read_exceptions()
537 		if (IS_ERR(area)) {  in read_exceptions()
538 			r = PTR_ERR(area);  in read_exceptions()
542 		r = insert_exceptions(ps, area, callback, callback_context,  in read_exceptions()
546 			memcpy(ps->area, area, ps->store->chunk_size << SECTOR_SHIFT);  in read_exceptions()
726 	 * filled this metadata area there's nothing more to do.  in persistent_commit_exception()
733 	 * If we completely filled the current area, then wipe the next one.  in persistent_commit_exception()
747 	 * Advance to the next area if this one is full.  in persistent_commit_exception()
773 	 * When current area is empty, move back to preceding area.  in persistent_prepare_merge()
789 	read_exception(ps, ps->area, ps->current_committed - 1, &ce);  in persistent_prepare_merge()
794 	 * Find number of consecutive chunks within the current area,  in persistent_prepare_merge()
799 		read_exception(ps, ps->area,  in persistent_prepare_merge()
864 	ps->area = NULL;  in persistent_ctr()
867 	ps->next_free = NUM_SNAPSHOT_HDR_CHUNKS + 1; /* header and 1st area */  in persistent_ctr()