Commit 9b696229 authored by Joe Thornber's avatar Joe Thornber Committed by Mike Snitzer
Browse files

dm persistent data: add cursor skip functions to the cursor APIs 



Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent 683bb1a3

drivers/md/persistent-data/dm-array.c

+21 −0
Original line number Diff line number Diff line
@@ -976,6 +976,27 @@ int dm_array_cursor_next(struct dm_array_cursor *c) 
}

EXPORT_SYMBOL_GPL(dm_array_cursor_next);



int dm_array_cursor_skip(struct dm_array_cursor *c, uint32_t count)

{

	int r;



	do {

		uint32_t remaining = le32_to_cpu(c->ab->nr_entries) - c->index;



		if (count < remaining) {

			c->index += count;

			return 0;

		}



		count -= remaining;

		r = dm_array_cursor_next(c);



	} while (!r);



	return r;

}

EXPORT_SYMBOL_GPL(dm_array_cursor_skip);



void dm_array_cursor_get_value(struct dm_array_cursor *c, void **value_le)

{

	*value_le = element_at(c->info, c->ab, c->index);

drivers/md/persistent-data/dm-array.h

+1 −0
Original line number Diff line number Diff line
@@ -207,6 +207,7 @@ void dm_array_cursor_end(struct dm_array_cursor *c); 


uint32_t dm_array_cursor_index(struct dm_array_cursor *c);

int dm_array_cursor_next(struct dm_array_cursor *c);

int dm_array_cursor_skip(struct dm_array_cursor *c, uint32_t count);



/*

 * value_le is only valid while the cursor points at the current value.

drivers/md/persistent-data/dm-bitset.c

+35 −0
Original line number Diff line number Diff line
@@ -273,6 +273,41 @@ int dm_bitset_cursor_next(struct dm_bitset_cursor *c) 
}

EXPORT_SYMBOL_GPL(dm_bitset_cursor_next);



int dm_bitset_cursor_skip(struct dm_bitset_cursor *c, uint32_t count)

{

	int r;

	__le64 *value;

	uint32_t nr_array_skip;

	uint32_t remaining_in_word = 64 - c->bit_index;



	if (c->entries_remaining < count)

		return -ENODATA;



	if (count < remaining_in_word) {

		c->bit_index += count;

		c->entries_remaining -= count;

		return 0;



	} else {

		c->entries_remaining -= remaining_in_word;

		count -= remaining_in_word;

	}



	nr_array_skip = (count / 64) + 1;

	r = dm_array_cursor_skip(&c->cursor, nr_array_skip);

	if (r)

		return r;



	dm_array_cursor_get_value(&c->cursor, (void **) &value);

	c->entries_remaining -= count;

	c->array_index += nr_array_skip;

	c->bit_index = count & 63;

	c->current_bits = le64_to_cpu(*value);



	return 0;

}

EXPORT_SYMBOL_GPL(dm_bitset_cursor_skip);



bool dm_bitset_cursor_get_value(struct dm_bitset_cursor *c)

{

	return test_bit(c->bit_index, (unsigned long *) &c->current_bits);

drivers/md/persistent-data/dm-bitset.h

+1 −0
Original line number Diff line number Diff line
@@ -197,6 +197,7 @@ int dm_bitset_cursor_begin(struct dm_disk_bitset *info, 
void dm_bitset_cursor_end(struct dm_bitset_cursor *c);



int dm_bitset_cursor_next(struct dm_bitset_cursor *c);

int dm_bitset_cursor_skip(struct dm_bitset_cursor *c, uint32_t count);

bool dm_bitset_cursor_get_value(struct dm_bitset_cursor *c);



/*----------------------------------------------------------------*/

drivers/md/persistent-data/dm-btree.c

+11 −0
Original line number Diff line number Diff line
@@ -1144,6 +1144,17 @@ int dm_btree_cursor_next(struct dm_btree_cursor *c) 
}

EXPORT_SYMBOL_GPL(dm_btree_cursor_next);



int dm_btree_cursor_skip(struct dm_btree_cursor *c, uint32_t count)

{

	int r = 0;



	while (count-- && !r)

		r = dm_btree_cursor_next(c);



	return r;

}

EXPORT_SYMBOL_GPL(dm_btree_cursor_skip);



int dm_btree_cursor_get_value(struct dm_btree_cursor *c, uint64_t *key, void *value_le)

{

	if (c->depth) {