[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"
#include "../os.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->file_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->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->verify != VERIFY_NONE)
			flags |= PROT_READ;
	} else
		flags = PROT_READ;

	f->mmap = mmap(NULL, f->file_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->file_size, MADV_SEQUENTIAL) < 0) {
			td_verror(td, errno, "madvise");
			goto err;
		}
	} else {
		if (madvise(f->mmap, f->file_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->file_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	#include "../os.h"
	17
	18	static int fio_mmapio_queue(struct thread_data td, struct io_u io_u)
	19	{
	20	struct fio_file *f = io_u->file;
	21	unsigned long long real_off = io_u->offset - f->file_offset;
	22
	23	if (io_u->ddir == DDIR_READ)
	24	memcpy(io_u->xfer_buf, f->mmap + real_off, io_u->xfer_buflen);
	25	else if (io_u->ddir == DDIR_WRITE)
	26	memcpy(f->mmap + real_off, io_u->xfer_buf, io_u->xfer_buflen);
	27	else if (io_u->ddir == DDIR_SYNC) {
	28	size_t len = (f->file_size + page_size - 1) & ~page_mask;
	29
	30	if (msync(f->mmap, len, MS_SYNC)) {
	31	io_u->error = errno;
	32	td_verror(td, io_u->error, "msync");
	33	}
	34	}
	35
	36	/*
	37	* not really direct, but should drop the pages from the cache
	38	*/
	39	if (td->odirect && io_u->ddir != DDIR_SYNC) {
	40	size_t len = (io_u->xfer_buflen + page_size - 1) & ~page_mask;
	41	unsigned long long off = real_off & ~page_mask;
	42
	43	if (msync(f->mmap + off, len, MS_SYNC) < 0) {
	44	io_u->error = errno;
	45	td_verror(td, io_u->error, "msync");
	46	}
	47	if (madvise(f->mmap + off, len, MADV_DONTNEED) < 0) {
	48	io_u->error = errno;
	49	td_verror(td, io_u->error, "madvise");
	50	}
	51	}
	52
	53	return FIO_Q_COMPLETED;
	54	}
	55
	56	static int fio_mmapio_open(struct thread_data td, struct fio_file f)
	57	{
	58	int ret, flags;
	59
	60	ret = generic_open_file(td, f);
	61	if (ret)
	62	return ret;
	63
	64	if (td_rw(td))
	65	flags = PROT_READ \| PROT_WRITE;
	66	else if (td_write(td)) {
	67	flags = PROT_WRITE;
	68
	69	if (td->verify != VERIFY_NONE)
	70	flags \|= PROT_READ;
	71	} else
	72	flags = PROT_READ;
	73
	74	f->mmap = mmap(NULL, f->file_size, flags, MAP_SHARED, f->fd, f->file_offset);
	75	if (f->mmap == MAP_FAILED) {
	76	f->mmap = NULL;
	77	td_verror(td, errno, "mmap");
	78	goto err;
	79	}
	80
	81	if (file_invalidate_cache(td, f))
	82	goto err;
	83
	84	if (!td_random(td)) {
	85	if (madvise(f->mmap, f->file_size, MADV_SEQUENTIAL) < 0) {
	86	td_verror(td, errno, "madvise");
	87	goto err;
	88	}
	89	} else {
	90	if (madvise(f->mmap, f->file_size, MADV_RANDOM) < 0) {
	91	td_verror(td, errno, "madvise");
	92	goto err;
	93	}
	94	}
	95
	96	return 0;
	97
	98	err:
	99	td->io_ops->close_file(td, f);
	100	return 1;
	101	}
	102
	103	static void fio_mmapio_close(struct thread_data fio_unused *td,
	104	struct fio_file *f)
	105	{
	106	if (f->mmap) {
	107	munmap(f->mmap, f->file_size);
	108	f->mmap = NULL;
	109	}
	110	generic_close_file(td, f);
	111	}
	112
	113	static struct ioengine_ops ioengine = {
	114	.name = "mmap",
	115	.version = FIO_IOOPS_VERSION,
	116	.queue = fio_mmapio_queue,
	117	.open_file = fio_mmapio_open,
	118	.close_file = fio_mmapio_close,
	119	.flags = FIO_SYNCIO \| FIO_NOEXTEND,
	120	};
	121
	122	static void fio_init fio_mmapio_register(void)
	123	{
	124	register_ioengine(&ioengine);
	125	}
	126
	127	static void fio_exit fio_mmapio_unregister(void)
	128	{
	129	unregister_ioengine(&ioengine);
	130	}