113 	void *area;  member
116 	 * An area of zeros used to clear the next area.
121 	 * An area used for header. The header can be written
128 	 * Used to keep track of which metadata area the data in
155 	 * metadata area.
176 	 * a single metadata area.  in alloc_area()
178 	ps->area = vmalloc(len);  in alloc_area()
179 	if (!ps->area)  in alloc_area()
196 	vfree(ps->area);  in alloc_area()
204 	vfree(ps->area);  in free_area()
205 	ps->area = NULL;  in free_area()
229 static int chunk_io(struct pstore *ps, void *area, chunk_t chunk, blk_opf_t opf,  in chunk_io()  argument
240 		.mem.ptr.vma = area,  in chunk_io()
265  * Convert a metadata area index to a chunk index.
267 static chunk_t area_location(struct pstore *ps, chunk_t area)  in area_location()  argument
269 	return NUM_SNAPSHOT_HDR_CHUNKS + ((ps->exceptions_per_area + 1) * area);  in area_location()
281  * Read or write a metadata area.  Remembering to skip the first
288 	return chunk_io(ps, ps->area, chunk, opf, 0);  in area_io()
293 	memset(ps->area, 0, ps->store->chunk_size << SECTOR_SHIFT);  in zero_memory_area()
296 static int zero_disk_area(struct pstore *ps, chunk_t area)  in zero_disk_area()  argument
298 	return chunk_io(ps, ps->zero_area, area_location(ps, area),  in zero_disk_area()
419 	struct disk_exception *de = get_exception(ps, ps->area, index);  in write_exception()
428 	struct disk_exception *de = get_exception(ps, ps->area, index);  in clear_exception()
436  * Registers the exceptions that are present in the current area.
437  * 'full' is filled in to indicate if the area has been
450 	/* presume the area is full */  in insert_exceptions()
458 		 * the COW device, where the first metadata area  in insert_exceptions()
460 		 * exceptions.  Therefore the area is not full.  in insert_exceptions()
508 	 * we find a partially full area.  in read_exceptions()
512 		void *area;  in read_exceptions()  local
530 		area = dm_bufio_read(client, chunk, &bp);  in read_exceptions()
531 		if (IS_ERR(area)) {  in read_exceptions()
532 			r = PTR_ERR(area);  in read_exceptions()
536 		r = insert_exceptions(ps, area, callback, callback_context,  in read_exceptions()
540 			memcpy(ps->area, area, ps->store->chunk_size << SECTOR_SHIFT);  in read_exceptions()
720 	 * filled this metadata area there's nothing more to do.  in persistent_commit_exception()
727 	 * If we completely filled the current area, then wipe the next one.  in persistent_commit_exception()
741 	 * Advance to the next area if this one is full.  in persistent_commit_exception()
767 	 * When current area is empty, move back to preceding area.  in persistent_prepare_merge()
783 	read_exception(ps, ps->area, ps->current_committed - 1, &ce);  in persistent_prepare_merge()
788 	 * Find number of consecutive chunks within the current area,  in persistent_prepare_merge()
793 		read_exception(ps, ps->area,  in persistent_prepare_merge()
858 	ps->area = NULL;  in persistent_ctr()
861 	ps->next_free = NUM_SNAPSHOT_HDR_CHUNKS + 1; /* header and 1st area */  in persistent_ctr()