zfs/module/os/freebsd/zfs/vdev_file.c - backupdr - Git at Google

 /*
  * CDDL HEADER START
  *
  * The contents of this file are subject to the terms of the
  * Common Development and Distribution License (the "License").
  * You may not use this file except in compliance with the License.
  *
  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  * or http://www.opensolaris.org/os/licensing.
  * See the License for the specific language governing permissions
  * and limitations under the License.
  *
  * When distributing Covered Code, include this CDDL HEADER in each
  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  * If applicable, add the following below this CDDL HEADER, with the
  * fields enclosed by brackets "[]" replaced with your own identifying
  * information: Portions Copyright [yyyy] [name of copyright owner]
  *
  * CDDL HEADER END
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2011, 2020 by Delphix. All rights reserved.
  */

 #include <sys/zfs_context.h>
 #include <sys/spa.h>
 #include <sys/file.h>
 #include <sys/vdev_file.h>
 #include <sys/vdev_impl.h>
 #include <sys/zio.h>
 #include <sys/fs/zfs.h>
 #include <sys/fm/fs/zfs.h>
 #include <sys/abd.h>
 #include <sys/stat.h>

 /*
  * Virtual device vector for files.
  */

 static taskq_t *vdev_file_taskq;

 unsigned long vdev_file_logical_ashift = SPA_MINBLOCKSHIFT;
 unsigned long vdev_file_physical_ashift = SPA_MINBLOCKSHIFT;

 void
 vdev_file_init(void)
 {
 	vdev_file_taskq = taskq_create("z_vdev_file", MAX(max_ncpus, 16),
 	    minclsyspri, max_ncpus, INT_MAX, 0);
 }

 void
 vdev_file_fini(void)
 {
 	taskq_destroy(vdev_file_taskq);
 }

 static void
 vdev_file_hold(vdev_t *vd)
 {
 	ASSERT3P(vd->vdev_path, !=, NULL);
 }

 static void
 vdev_file_rele(vdev_t *vd)
 {
 	ASSERT3P(vd->vdev_path, !=, NULL);
 }

 static mode_t
 vdev_file_open_mode(spa_mode_t spa_mode)
 {
 	mode_t mode = 0;

 	if ((spa_mode & SPA_MODE_READ) && (spa_mode & SPA_MODE_WRITE)) {
 		mode = O_RDWR;
 	} else if (spa_mode & SPA_MODE_READ) {
 		mode = O_RDONLY;
 	} else if (spa_mode & SPA_MODE_WRITE) {
 		mode = O_WRONLY;
 	}

 	return (mode | O_LARGEFILE);
 }

 static int
 vdev_file_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize,
     uint64_t *logical_ashift, uint64_t *physical_ashift)
 {
 	vdev_file_t *vf;
 	zfs_file_t *fp;
 	zfs_file_attr_t zfa;
 	int error;

 	/*
 	 * Rotational optimizations only make sense on block devices.
 	 */
 	vd->vdev_nonrot = B_TRUE;

 	/*
 	 * Allow TRIM on file based vdevs.  This may not always be supported,
 	 * since it depends on your kernel version and underlying filesystem
 	 * type but it is always safe to attempt.
 	 */
 	vd->vdev_has_trim = B_TRUE;

 	/*
 	 * Disable secure TRIM on file based vdevs.  There is no way to
 	 * request this behavior from the underlying filesystem.
 	 */
 	vd->vdev_has_securetrim = B_FALSE;

 	/*
 	 * We must have a pathname, and it must be absolute.
 	 */
 	if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') {
 		vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
 		return (SET_ERROR(EINVAL));
 	}

 	/*
 	 * Reopen the device if it's not currently open.  Otherwise,
 	 * just update the physical size of the device.
 	 */
 	if (vd->vdev_tsd != NULL) {
 		ASSERT(vd->vdev_reopening);
 		vf = vd->vdev_tsd;
 		goto skip_open;
 	}

 	vf = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_file_t), KM_SLEEP);

 	/*
 	 * We always open the files from the root of the global zone, even if
 	 * we're in a local zone.  If the user has gotten to this point, the
 	 * administrator has already decided that the pool should be available
 	 * to local zone users, so the underlying devices should be as well.
 	 */
 	ASSERT3P(vd->vdev_path, !=, NULL);
 	ASSERT(vd->vdev_path[0] == '/');

 	error = zfs_file_open(vd->vdev_path,
 	    vdev_file_open_mode(spa_mode(vd->vdev_spa)), 0, &fp);
 	if (error) {
 		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
 		return (error);
 	}

 	vf->vf_file = fp;

 #ifdef _KERNEL
 	/*
 	 * Make sure it's a regular file.
 	 */
 	if (zfs_file_getattr(fp, &zfa)) {
 		return (SET_ERROR(ENODEV));
 	}
 	if (!S_ISREG(zfa.zfa_mode)) {
 		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
 		return (SET_ERROR(ENODEV));
 	}
 #endif

 skip_open:

 	error =  zfs_file_getattr(vf->vf_file, &zfa);
 	if (error) {
 		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
 		return (error);
 	}

 	*max_psize = *psize = zfa.zfa_size;
 	*logical_ashift = vdev_file_logical_ashift;
 	*physical_ashift = vdev_file_physical_ashift;

 	return (0);
 }

 static void
 vdev_file_close(vdev_t *vd)
 {
 	vdev_file_t *vf = vd->vdev_tsd;

 	if (vd->vdev_reopening || vf == NULL)
 		return;

 	if (vf->vf_file != NULL) {
 		zfs_file_close(vf->vf_file);
 	}

 	vd->vdev_delayed_close = B_FALSE;
 	kmem_free(vf, sizeof (vdev_file_t));
 	vd->vdev_tsd = NULL;
 }

 /*
  * Implements the interrupt side for file vdev types. This routine will be
  * called when the I/O completes allowing us to transfer the I/O to the
  * interrupt taskqs. For consistency, the code structure mimics disk vdev
  * types.
  */
 static void
 vdev_file_io_intr(zio_t *zio)
 {
 	zio_delay_interrupt(zio);
 }

 static void
 vdev_file_io_strategy(void *arg)
 {
 	zio_t *zio = arg;
 	vdev_t *vd = zio->io_vd;
 	vdev_file_t *vf;
 	void *buf;
 	ssize_t resid;
 	loff_t off;
 	ssize_t size;
 	int err;

 	off = zio->io_offset;
 	size = zio->io_size;
 	resid = 0;

 	vf = vd->vdev_tsd;

 	ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE);
 	if (zio->io_type == ZIO_TYPE_READ) {
 		buf = abd_borrow_buf(zio->io_abd, zio->io_size);
 		err = zfs_file_pread(vf->vf_file, buf, size, off, &resid);
 		abd_return_buf_copy(zio->io_abd, buf, size);
 	} else {
 		buf = abd_borrow_buf_copy(zio->io_abd, zio->io_size);
 		err = zfs_file_pwrite(vf->vf_file, buf, size, off, &resid);
 		abd_return_buf(zio->io_abd, buf, size);
 	}
 	zio->io_error = err;
 	if (resid != 0 && zio->io_error == 0)
 		zio->io_error = ENOSPC;

 	vdev_file_io_intr(zio);
 }

 static void
 vdev_file_io_start(zio_t *zio)
 {
 	vdev_t *vd = zio->io_vd;
 	vdev_file_t *vf = vd->vdev_tsd;

 	if (zio->io_type == ZIO_TYPE_IOCTL) {
 		/* XXPOLICY */
 		if (!vdev_readable(vd)) {
 			zio->io_error = SET_ERROR(ENXIO);
 			zio_interrupt(zio);
 			return;
 		}

 		switch (zio->io_cmd) {
 		case DKIOCFLUSHWRITECACHE:
 			zio->io_error = zfs_file_fsync(vf->vf_file,
 			    O_SYNC|O_DSYNC);
 			break;
 		default:
 			zio->io_error = SET_ERROR(ENOTSUP);
 		}

 		zio_execute(zio);
 		return;
 	} else if (zio->io_type == ZIO_TYPE_TRIM) {
 #ifdef notyet
 		int mode = 0;

 		ASSERT3U(zio->io_size, !=, 0);

 		/* XXX FreeBSD has no fallocate routine in file ops */
 		zio->io_error = zfs_file_fallocate(vf->vf_file,
 		    mode, zio->io_offset, zio->io_size);
 #endif
 		zio->io_error = SET_ERROR(ENOTSUP);
 		zio_execute(zio);
 		return;
 	}
 	ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE);
 	zio->io_target_timestamp = zio_handle_io_delay(zio);

 	VERIFY3U(taskq_dispatch(vdev_file_taskq, vdev_file_io_strategy, zio,
 	    TQ_SLEEP), !=, 0);
 }

 static void
 vdev_file_io_done(zio_t *zio)
 {
 	(void) zio;
 }

 vdev_ops_t vdev_file_ops = {
 	.vdev_op_init = NULL,
 	.vdev_op_fini = NULL,
 	.vdev_op_open = vdev_file_open,
 	.vdev_op_close = vdev_file_close,
 	.vdev_op_asize = vdev_default_asize,
 	.vdev_op_min_asize = vdev_default_min_asize,
 	.vdev_op_min_alloc = NULL,
 	.vdev_op_io_start = vdev_file_io_start,
 	.vdev_op_io_done = vdev_file_io_done,
 	.vdev_op_state_change = NULL,
 	.vdev_op_need_resilver = NULL,
 	.vdev_op_hold = vdev_file_hold,
 	.vdev_op_rele = vdev_file_rele,
 	.vdev_op_remap = NULL,
 	.vdev_op_xlate = vdev_default_xlate,
 	.vdev_op_rebuild_asize = NULL,
 	.vdev_op_metaslab_init = NULL,
 	.vdev_op_config_generate = NULL,
 	.vdev_op_nparity = NULL,
 	.vdev_op_ndisks = NULL,
 	.vdev_op_type = VDEV_TYPE_FILE,		/* name of this vdev type */
 	.vdev_op_leaf = B_TRUE			/* leaf vdev */
 };

 /*
  * From userland we access disks just like files.
  */
 #ifndef _KERNEL

 vdev_ops_t vdev_disk_ops = {
 	.vdev_op_init = NULL,
 	.vdev_op_fini = NULL,
 	.vdev_op_open = vdev_file_open,
 	.vdev_op_close = vdev_file_close,
 	.vdev_op_asize = vdev_default_asize,
 	.vdev_op_min_asize = vdev_default_min_asize,
 	.vdev_op_min_alloc = NULL,
 	.vdev_op_io_start = vdev_file_io_start,
 	.vdev_op_io_done = vdev_file_io_done,
 	.vdev_op_state_change = NULL,
 	.vdev_op_need_resilver = NULL,
 	.vdev_op_hold = vdev_file_hold,
 	.vdev_op_rele = vdev_file_rele,
 	.vdev_op_remap = NULL,
 	.vdev_op_xlate = vdev_default_xlate,
 	.vdev_op_rebuild_asize = NULL,
 	.vdev_op_metaslab_init = NULL,
 	.vdev_op_config_generate = NULL,
 	.vdev_op_nparity = NULL,
 	.vdev_op_ndisks = NULL,
 	.vdev_op_type = VDEV_TYPE_DISK,		/* name of this vdev type */
 	.vdev_op_leaf = B_TRUE			/* leaf vdev */
 };

 #endif

 ZFS_MODULE_PARAM(zfs_vdev_file, vdev_file_, logical_ashift, ULONG, ZMOD_RW,
 	"Logical ashift for file-based devices");
 ZFS_MODULE_PARAM(zfs_vdev_file, vdev_file_, physical_ashift, ULONG, ZMOD_RW,
 	"Physical ashift for file-based devices");
	/*
	* CDDL HEADER START
	*
	* The contents of this file are subject to the terms of the
	* Common Development and Distribution License (the "License").
	* You may not use this file except in compliance with the License.
	*
	* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
	* or http://www.opensolaris.org/os/licensing.
	* See the License for the specific language governing permissions
	* and limitations under the License.
	*
	* When distributing Covered Code, include this CDDL HEADER in each
	* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
	* If applicable, add the following below this CDDL HEADER, with the
	* fields enclosed by brackets "[]" replaced with your own identifying
	* information: Portions Copyright [yyyy] [name of copyright owner]
	*
	* CDDL HEADER END
	*/
	/*
	* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
	* Copyright (c) 2011, 2020 by Delphix. All rights reserved.
	*/

	#include <sys/zfs_context.h>
	#include <sys/spa.h>
	#include <sys/file.h>
	#include <sys/vdev_file.h>
	#include <sys/vdev_impl.h>
	#include <sys/zio.h>
	#include <sys/fs/zfs.h>
	#include <sys/fm/fs/zfs.h>
	#include <sys/abd.h>
	#include <sys/stat.h>

	/*
	* Virtual device vector for files.
	*/

	static taskq_t *vdev_file_taskq;

	unsigned long vdev_file_logical_ashift = SPA_MINBLOCKSHIFT;
	unsigned long vdev_file_physical_ashift = SPA_MINBLOCKSHIFT;

	void
	vdev_file_init(void)
	{
	vdev_file_taskq = taskq_create("z_vdev_file", MAX(max_ncpus, 16),
	minclsyspri, max_ncpus, INT_MAX, 0);
	}

	void
	vdev_file_fini(void)
	{
	taskq_destroy(vdev_file_taskq);
	}

	static void
	vdev_file_hold(vdev_t *vd)
	{
	ASSERT3P(vd->vdev_path, !=, NULL);
	}

	static void
	vdev_file_rele(vdev_t *vd)
	{
	ASSERT3P(vd->vdev_path, !=, NULL);
	}

	static mode_t
	vdev_file_open_mode(spa_mode_t spa_mode)
	{
	mode_t mode = 0;

	if ((spa_mode & SPA_MODE_READ) && (spa_mode & SPA_MODE_WRITE)) {
	mode = O_RDWR;
	} else if (spa_mode & SPA_MODE_READ) {
	mode = O_RDONLY;
	} else if (spa_mode & SPA_MODE_WRITE) {
	mode = O_WRONLY;
	}

	return (mode \| O_LARGEFILE);
	}

	static int
	vdev_file_open(vdev_t vd, uint64_t psize, uint64_t *max_psize,
	uint64_t logical_ashift, uint64_t physical_ashift)
	{
	vdev_file_t *vf;
	zfs_file_t *fp;
	zfs_file_attr_t zfa;
	int error;

	/*
	* Rotational optimizations only make sense on block devices.
	*/
	vd->vdev_nonrot = B_TRUE;

	/*
	* Allow TRIM on file based vdevs. This may not always be supported,
	* since it depends on your kernel version and underlying filesystem
	* type but it is always safe to attempt.
	*/
	vd->vdev_has_trim = B_TRUE;

	/*
	* Disable secure TRIM on file based vdevs. There is no way to
	* request this behavior from the underlying filesystem.
	*/
	vd->vdev_has_securetrim = B_FALSE;

	/*
	* We must have a pathname, and it must be absolute.
	*/
	if (vd->vdev_path == NULL \|\| vd->vdev_path[0] != '/') {
	vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
	return (SET_ERROR(EINVAL));
	}

	/*
	* Reopen the device if it's not currently open. Otherwise,
	* just update the physical size of the device.
	*/
	if (vd->vdev_tsd != NULL) {
	ASSERT(vd->vdev_reopening);
	vf = vd->vdev_tsd;
	goto skip_open;
	}

	vf = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_file_t), KM_SLEEP);

	/*
	* We always open the files from the root of the global zone, even if
	* we're in a local zone. If the user has gotten to this point, the
	* administrator has already decided that the pool should be available
	* to local zone users, so the underlying devices should be as well.
	*/
	ASSERT3P(vd->vdev_path, !=, NULL);
	ASSERT(vd->vdev_path[0] == '/');

	error = zfs_file_open(vd->vdev_path,
	vdev_file_open_mode(spa_mode(vd->vdev_spa)), 0, &fp);
	if (error) {
	vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
	return (error);
	}

	vf->vf_file = fp;

	#ifdef _KERNEL
	/*
	* Make sure it's a regular file.
	*/
	if (zfs_file_getattr(fp, &zfa)) {
	return (SET_ERROR(ENODEV));
	}
	if (!S_ISREG(zfa.zfa_mode)) {
	vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
	return (SET_ERROR(ENODEV));
	}
	#endif

	skip_open:

	error = zfs_file_getattr(vf->vf_file, &zfa);
	if (error) {
	vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
	return (error);
	}

	max_psize = psize = zfa.zfa_size;
	*logical_ashift = vdev_file_logical_ashift;
	*physical_ashift = vdev_file_physical_ashift;

	return (0);
	}

	static void
	vdev_file_close(vdev_t *vd)
	{
	vdev_file_t *vf = vd->vdev_tsd;

	if (vd->vdev_reopening \|\| vf == NULL)
	return;

	if (vf->vf_file != NULL) {
	zfs_file_close(vf->vf_file);
	}

	vd->vdev_delayed_close = B_FALSE;
	kmem_free(vf, sizeof (vdev_file_t));
	vd->vdev_tsd = NULL;
	}

	/*
	* Implements the interrupt side for file vdev types. This routine will be
	* called when the I/O completes allowing us to transfer the I/O to the
	* interrupt taskqs. For consistency, the code structure mimics disk vdev
	* types.
	*/
	static void
	vdev_file_io_intr(zio_t *zio)
	{
	zio_delay_interrupt(zio);
	}

	static void
	vdev_file_io_strategy(void *arg)
	{
	zio_t *zio = arg;
	vdev_t *vd = zio->io_vd;
	vdev_file_t *vf;
	void *buf;
	ssize_t resid;
	loff_t off;
	ssize_t size;
	int err;

	off = zio->io_offset;
	size = zio->io_size;
	resid = 0;

	vf = vd->vdev_tsd;

	ASSERT(zio->io_type == ZIO_TYPE_READ \|\| zio->io_type == ZIO_TYPE_WRITE);
	if (zio->io_type == ZIO_TYPE_READ) {
	buf = abd_borrow_buf(zio->io_abd, zio->io_size);
	err = zfs_file_pread(vf->vf_file, buf, size, off, &resid);
	abd_return_buf_copy(zio->io_abd, buf, size);
	} else {
	buf = abd_borrow_buf_copy(zio->io_abd, zio->io_size);
	err = zfs_file_pwrite(vf->vf_file, buf, size, off, &resid);
	abd_return_buf(zio->io_abd, buf, size);
	}
	zio->io_error = err;
	if (resid != 0 && zio->io_error == 0)
	zio->io_error = ENOSPC;

	vdev_file_io_intr(zio);
	}

	static void
	vdev_file_io_start(zio_t *zio)
	{
	vdev_t *vd = zio->io_vd;
	vdev_file_t *vf = vd->vdev_tsd;

	if (zio->io_type == ZIO_TYPE_IOCTL) {
	/* XXPOLICY */
	if (!vdev_readable(vd)) {
	zio->io_error = SET_ERROR(ENXIO);
	zio_interrupt(zio);
	return;
	}

	switch (zio->io_cmd) {
	case DKIOCFLUSHWRITECACHE:
	zio->io_error = zfs_file_fsync(vf->vf_file,
	O_SYNC\|O_DSYNC);
	break;
	default:
	zio->io_error = SET_ERROR(ENOTSUP);
	}

	zio_execute(zio);
	return;
	} else if (zio->io_type == ZIO_TYPE_TRIM) {
	#ifdef notyet
	int mode = 0;

	ASSERT3U(zio->io_size, !=, 0);

	/* XXX FreeBSD has no fallocate routine in file ops */
	zio->io_error = zfs_file_fallocate(vf->vf_file,
	mode, zio->io_offset, zio->io_size);
	#endif
	zio->io_error = SET_ERROR(ENOTSUP);
	zio_execute(zio);
	return;
	}
	ASSERT(zio->io_type == ZIO_TYPE_READ \|\| zio->io_type == ZIO_TYPE_WRITE);
	zio->io_target_timestamp = zio_handle_io_delay(zio);

	VERIFY3U(taskq_dispatch(vdev_file_taskq, vdev_file_io_strategy, zio,
	TQ_SLEEP), !=, 0);
	}

	static void
	vdev_file_io_done(zio_t *zio)
	{
	(void) zio;
	}

	vdev_ops_t vdev_file_ops = {
	.vdev_op_init = NULL,
	.vdev_op_fini = NULL,
	.vdev_op_open = vdev_file_open,
	.vdev_op_close = vdev_file_close,
	.vdev_op_asize = vdev_default_asize,
	.vdev_op_min_asize = vdev_default_min_asize,
	.vdev_op_min_alloc = NULL,
	.vdev_op_io_start = vdev_file_io_start,
	.vdev_op_io_done = vdev_file_io_done,
	.vdev_op_state_change = NULL,
	.vdev_op_need_resilver = NULL,
	.vdev_op_hold = vdev_file_hold,
	.vdev_op_rele = vdev_file_rele,
	.vdev_op_remap = NULL,
	.vdev_op_xlate = vdev_default_xlate,
	.vdev_op_rebuild_asize = NULL,
	.vdev_op_metaslab_init = NULL,
	.vdev_op_config_generate = NULL,
	.vdev_op_nparity = NULL,
	.vdev_op_ndisks = NULL,
	.vdev_op_type = VDEV_TYPE_FILE, /* name of this vdev type */
	.vdev_op_leaf = B_TRUE /* leaf vdev */
	};

	/*
	* From userland we access disks just like files.
	*/
	#ifndef _KERNEL

	vdev_ops_t vdev_disk_ops = {
	.vdev_op_init = NULL,
	.vdev_op_fini = NULL,
	.vdev_op_open = vdev_file_open,
	.vdev_op_close = vdev_file_close,
	.vdev_op_asize = vdev_default_asize,
	.vdev_op_min_asize = vdev_default_min_asize,
	.vdev_op_min_alloc = NULL,
	.vdev_op_io_start = vdev_file_io_start,
	.vdev_op_io_done = vdev_file_io_done,
	.vdev_op_state_change = NULL,
	.vdev_op_need_resilver = NULL,
	.vdev_op_hold = vdev_file_hold,
	.vdev_op_rele = vdev_file_rele,
	.vdev_op_remap = NULL,
	.vdev_op_xlate = vdev_default_xlate,
	.vdev_op_rebuild_asize = NULL,
	.vdev_op_metaslab_init = NULL,
	.vdev_op_config_generate = NULL,
	.vdev_op_nparity = NULL,
	.vdev_op_ndisks = NULL,
	.vdev_op_type = VDEV_TYPE_DISK, /* name of this vdev type */
	.vdev_op_leaf = B_TRUE /* leaf vdev */
	};

	#endif

	ZFS_MODULE_PARAM(zfs_vdev_file, vdev_file_, logical_ashift, ULONG, ZMOD_RW,
	"Logical ashift for file-based devices");
	ZFS_MODULE_PARAM(zfs_vdev_file, vdev_file_, physical_ashift, ULONG, ZMOD_RW,
	"Physical ashift for file-based devices");