[fio.git] / engines / mmap.c

/*
 * mmap engine
 *
 * IO engine that reads/writes from files by doing memcpy to/from
 * a memory mapped region of the file.
 *
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <assert.h>
#include <sys/mman.h>

#include "../fio.h"

static int fio_mmapio_queue(struct thread_data *td, struct io_u *io_u)
{
	struct fio_file *f = io_u->file;
	unsigned long long real_off = io_u->offset - f->file_offset;

	if (io_u->ddir == DDIR_READ)
		memcpy(io_u->xfer_buf, f->mmap + real_off, io_u->xfer_buflen);
	else if (io_u->ddir == DDIR_WRITE)
		memcpy(f->mmap + real_off, io_u->xfer_buf, io_u->xfer_buflen);
	else if (io_u->ddir == DDIR_SYNC) {
		size_t len = (f->io_size + page_size - 1) & ~page_mask;

		if (msync(f->mmap, len, MS_SYNC)) {
			io_u->error = errno;
			td_verror(td, io_u->error, "msync");
		}
	}

	/*
	 * not really direct, but should drop the pages from the cache
	 */
	if (td->o.odirect && io_u->ddir != DDIR_SYNC) {
		size_t len = (io_u->xfer_buflen + page_size - 1) & ~page_mask;
		unsigned long long off = real_off & ~page_mask;

		if (msync(f->mmap + off, len, MS_SYNC) < 0) {
			io_u->error = errno;
			td_verror(td, io_u->error, "msync");
		}
		if (madvise(f->mmap + off, len,  MADV_DONTNEED) < 0) {
			io_u->error = errno;
			td_verror(td, io_u->error, "madvise");
		}
	}

	return FIO_Q_COMPLETED;
}

static int fio_mmapio_open(struct thread_data *td, struct fio_file *f)
{
	int ret, flags;

	ret = generic_open_file(td, f);
	if (ret)
		return ret;

	if (td_rw(td))
		flags = PROT_READ | PROT_WRITE;
	else if (td_write(td)) {
		flags = PROT_WRITE;

		if (td->o.verify != VERIFY_NONE)
			flags |= PROT_READ;
	} else
		flags = PROT_READ;

	f->mmap = mmap(NULL, f->io_size, flags, MAP_SHARED, f->fd, f->file_offset);
	if (f->mmap == MAP_FAILED) {
		f->mmap = NULL;
		td_verror(td, errno, "mmap");
		goto err;
	}

	if (file_invalidate_cache(td, f))
		goto err;

	if (!td_random(td)) {
		if (madvise(f->mmap, f->io_size, MADV_SEQUENTIAL) < 0) {
			td_verror(td, errno, "madvise");
			goto err;
		}
	} else {
		if (madvise(f->mmap, f->io_size, MADV_RANDOM) < 0) {
			td_verror(td, errno, "madvise");
			goto err;
		}
	}

	return 0;

err:
	td->io_ops->close_file(td, f);
	return 1;
}

static void fio_mmapio_close(struct thread_data fio_unused *td,
			     struct fio_file *f)
{
	if (f->mmap) {
		munmap(f->mmap, f->io_size);
		f->mmap = NULL;
	}
	generic_close_file(td, f);
}

static struct ioengine_ops ioengine = {
	.name		= "mmap",
	.version	= FIO_IOOPS_VERSION,
	.queue		= fio_mmapio_queue,
	.open_file	= fio_mmapio_open,
	.close_file	= fio_mmapio_close,
	.flags		= FIO_SYNCIO | FIO_NOEXTEND,
};

static void fio_init fio_mmapio_register(void)
{
	register_ioengine(&ioengine);
}

static void fio_exit fio_mmapio_unregister(void)
{
	unregister_ioengine(&ioengine);
}
Commit	Line	Data
	1	/*
	2	* mmap engine
	3	*
	4	* IO engine that reads/writes from files by doing memcpy to/from
	5	* a memory mapped region of the file.
	6	*
	7	*/
	8	#include <stdio.h>
	9	#include <stdlib.h>
	10	#include <unistd.h>
	11	#include <errno.h>
	12	#include <assert.h>
	13	#include <sys/mman.h>
	14
	15	#include "../fio.h"
	16
	17	static int fio_mmapio_queue(struct thread_data td, struct io_u io_u)
	18	{
	19	struct fio_file *f = io_u->file;
	20	unsigned long long real_off = io_u->offset - f->file_offset;
	21
	22	if (io_u->ddir == DDIR_READ)
	23	memcpy(io_u->xfer_buf, f->mmap + real_off, io_u->xfer_buflen);
	24	else if (io_u->ddir == DDIR_WRITE)
	25	memcpy(f->mmap + real_off, io_u->xfer_buf, io_u->xfer_buflen);
	26	else if (io_u->ddir == DDIR_SYNC) {
	27	size_t len = (f->io_size + page_size - 1) & ~page_mask;
	28
	29	if (msync(f->mmap, len, MS_SYNC)) {
	30	io_u->error = errno;
	31	td_verror(td, io_u->error, "msync");
	32	}
	33	}
	34
	35	/*
	36	* not really direct, but should drop the pages from the cache
	37	*/
	38	if (td->o.odirect && io_u->ddir != DDIR_SYNC) {
	39	size_t len = (io_u->xfer_buflen + page_size - 1) & ~page_mask;
	40	unsigned long long off = real_off & ~page_mask;
	41
	42	if (msync(f->mmap + off, len, MS_SYNC) < 0) {
	43	io_u->error = errno;
	44	td_verror(td, io_u->error, "msync");
	45	}
	46	if (madvise(f->mmap + off, len, MADV_DONTNEED) < 0) {
	47	io_u->error = errno;
	48	td_verror(td, io_u->error, "madvise");
	49	}
	50	}
	51
	52	return FIO_Q_COMPLETED;
	53	}
	54
	55	static int fio_mmapio_open(struct thread_data td, struct fio_file f)
	56	{
	57	int ret, flags;
	58
	59	ret = generic_open_file(td, f);
	60	if (ret)
	61	return ret;
	62
	63	if (td_rw(td))
	64	flags = PROT_READ \| PROT_WRITE;
	65	else if (td_write(td)) {
	66	flags = PROT_WRITE;
	67
	68	if (td->o.verify != VERIFY_NONE)
	69	flags \|= PROT_READ;
	70	} else
	71	flags = PROT_READ;
	72
	73	f->mmap = mmap(NULL, f->io_size, flags, MAP_SHARED, f->fd, f->file_offset);
	74	if (f->mmap == MAP_FAILED) {
	75	f->mmap = NULL;
	76	td_verror(td, errno, "mmap");
	77	goto err;
	78	}
	79
	80	if (file_invalidate_cache(td, f))
	81	goto err;
	82
	83	if (!td_random(td)) {
	84	if (madvise(f->mmap, f->io_size, MADV_SEQUENTIAL) < 0) {
	85	td_verror(td, errno, "madvise");
	86	goto err;
	87	}
	88	} else {
	89	if (madvise(f->mmap, f->io_size, MADV_RANDOM) < 0) {
	90	td_verror(td, errno, "madvise");
	91	goto err;
	92	}
	93	}
	94
	95	return 0;
	96
	97	err:
	98	td->io_ops->close_file(td, f);
	99	return 1;
	100	}
	101
	102	static void fio_mmapio_close(struct thread_data fio_unused *td,
	103	struct fio_file *f)
	104	{
	105	if (f->mmap) {
	106	munmap(f->mmap, f->io_size);
	107	f->mmap = NULL;
	108	}
	109	generic_close_file(td, f);
	110	}
	111
	112	static struct ioengine_ops ioengine = {
	113	.name = "mmap",
	114	.version = FIO_IOOPS_VERSION,
	115	.queue = fio_mmapio_queue,
	116	.open_file = fio_mmapio_open,
	117	.close_file = fio_mmapio_close,
	118	.flags = FIO_SYNCIO \| FIO_NOEXTEND,
	119	};
	120
	121	static void fio_init fio_mmapio_register(void)
	122	{
	123	register_ioengine(&ioengine);
	124	}
	125
	126	static void fio_exit fio_mmapio_unregister(void)
	127	{
	128	unregister_ioengine(&ioengine);
	129	}