/*

 * TRIM/DISCARD support

 */

#include <string.h>

#include <assert.h>

#include "fio.h"

#include "trim.h"

#ifdef FIO_HAVE_TRIM

bool get_next_trim(struct thread_data *td, struct io_u *io_u)

{

	struct io_piece *ipo;

	/*

	 * this io_u is from a requeue, we already filled the offsets

	 */

	if (io_u->file)

		return true;

	if (flist_empty(&td->trim_list))

		return false;

	assert(td->trim_entries);

	ipo = flist_first_entry(&td->trim_list, struct io_piece, trim_list);

	remove_trim_entry(td, ipo);

	io_u->offset = ipo->offset;

	io_u->buflen = ipo->len;

	io_u->file = ipo->file;

	/*

	 * If not verifying that trimmed ranges return zeroed data,

	 * remove this from the to-read verify lists

	 */

	if (!td->o.trim_zero) {

		if (ipo->flags & IP_F_ONLIST)

			flist_del(&ipo->list);

		else {

			assert(ipo->flags & IP_F_ONRB);

			rb_erase(&ipo->rb_node, &td->io_hist_tree);

		}

		td->io_hist_len--;

		free(ipo);

	} else

		ipo->flags |= IP_F_TRIMMED;

	if (!fio_file_open(io_u->file)) {

		int r = td_io_open_file(td, io_u->file);

		if (r) {

			dprint(FD_VERIFY, "failed file %s open\n",

					io_u->file->file_name);

			return false;

		}

	}

	get_file(io_u->file);

	assert(fio_file_open(io_u->file));

	io_u->ddir = DDIR_TRIM;

	io_u->xfer_buf = NULL;

	io_u->xfer_buflen = io_u->buflen;

	dprint(FD_VERIFY, "get_next_trim: ret io_u %p\n", io_u);

	return true;

}

bool io_u_should_trim(struct thread_data *td, struct io_u *io_u)

{

	unsigned long long val;

	uint64_t frand_max;

	unsigned long r;

	if (!td->o.trim_percentage)

		return false;

	frand_max = rand_max(&td->trim_state);

	r = __rand(&td->trim_state);

	val = (frand_max / 100ULL);

	val *= (unsigned long long) td->o.trim_percentage;

	return r <= val;

}

#endif