[apple/xnu.git] / bsd / vm / vm_compressor_backing_file.c

/*
 * Copyright (c) 2000-2013 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

#include <stdint.h>
#include <sys/fcntl.h>
#include <sys/vnode_internal.h>
#include <sys/vnode.h>
#include <sys/kauth.h>
#include <sys/mount_internal.h>
#include <sys/buf_internal.h>
#include <kern/debug.h>
#include <kern/kalloc.h>
#include <sys/cprotect.h>
#include <sys/disk.h>
#include <vm/vm_protos.h>
#include <vm/vm_pageout.h>

void vm_swapfile_open(const char *path, vnode_t *vp);
void vm_swapfile_close(uint64_t path, vnode_t vp);
int vm_swapfile_preallocate(vnode_t vp, uint64_t *size, boolean_t *pin);
uint64_t vm_swapfile_get_blksize(vnode_t vp);
uint64_t vm_swapfile_get_transfer_size(vnode_t vp);
int vm_swapfile_io(vnode_t vp, uint64_t offset, uint64_t start, int npages, int flags);
int vm_record_file_write(struct vnode *vp, uint64_t offset, char *buf, int size);


void
vm_swapfile_open(const char *path, vnode_t *vp)
{
	int error = 0;
	vfs_context_t	ctx = vfs_context_current();

	if ((error = vnode_open(path, (O_CREAT | O_TRUNC | FREAD | FWRITE), S_IRUSR | S_IWUSR, 0, vp, ctx))) {
		printf("Failed to open swap file %d\n", error);
		*vp = NULL;
		return;
	}	

	vnode_put(*vp);
}

uint64_t
vm_swapfile_get_blksize(vnode_t vp)
{
	return ((uint64_t)vfs_devblocksize(vnode_mount(vp)));
}

uint64_t
vm_swapfile_get_transfer_size(vnode_t vp)
{
	return((uint64_t)vp->v_mount->mnt_vfsstat.f_iosize);
}

int unlink1(vfs_context_t, vnode_t, user_addr_t, enum uio_seg, int);

void
vm_swapfile_close(uint64_t path_addr, vnode_t vp)
{
	vfs_context_t context = vfs_context_current();
	int error;

	vnode_getwithref(vp);
	vnode_close(vp, 0, context);
	
	error = unlink1(context, NULLVP, CAST_USER_ADDR_T(path_addr),
	    UIO_SYSSPACE, 0);

#if DEVELOPMENT || DEBUG
	if (error)
		printf("%s : unlink of %s failed with error %d", __FUNCTION__,
		    (char *)path_addr, error);
#endif
}

int
vm_swapfile_preallocate(vnode_t vp, uint64_t *size, boolean_t *pin)
{
	int		error = 0;
	uint64_t	file_size = 0;
	vfs_context_t	ctx = NULL;


	ctx = vfs_context_current();

	error = vnode_setsize(vp, *size, IO_NOZEROFILL, ctx);

	if (error) {
		printf("vnode_setsize for swap files failed: %d\n", error);
		goto done;
	}

	error = vnode_size(vp, (off_t*) &file_size, ctx);

	if (error) {
		printf("vnode_size (new file) for swap file failed: %d\n", error);
		goto done;
	}	
	assert(file_size == *size);
	
	if (pin != NULL && *pin != FALSE) {
		error = VNOP_IOCTL(vp, FIOPINSWAP, NULL, 0, ctx);

		if (error) {
			printf("pin for swap files failed: %d,  file_size = %lld\n", error, file_size);
			/* this is not fatal, carry on with files wherever they landed */
			*pin = FALSE;
			error = 0;
		}
	}

	vnode_lock_spin(vp);
	SET(vp->v_flag, VSWAP);
	vnode_unlock(vp);
done:
	return error;
}


int
vm_record_file_write(vnode_t vp, uint64_t offset, char *buf, int size)
{
	int error = 0;
	vfs_context_t ctx;

	ctx = vfs_context_kernel();
		
	error = vn_rdwr(UIO_WRITE, vp, (caddr_t)buf, size, offset,
		UIO_SYSSPACE, IO_NODELOCKED, vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx));

	return (error);
}


int
vm_swapfile_io(vnode_t vp, uint64_t offset, uint64_t start, int npages, int flags)
{
	int error = 0;
	uint64_t io_size = npages * PAGE_SIZE_64;
#if 1
	kern_return_t	kr = KERN_SUCCESS;
	upl_t		upl = NULL;
	unsigned int	count = 0;
	upl_control_flags_t upl_create_flags = 0;
	int		upl_control_flags = 0;
	upl_size_t	upl_size = 0;

	upl_create_flags = UPL_SET_INTERNAL | UPL_SET_LITE
			| UPL_MEMORY_TAG_MAKE(VM_KERN_MEMORY_OSFMK);

#if ENCRYPTED_SWAP
	upl_control_flags = UPL_IOSYNC | UPL_PAGING_ENCRYPTED;
#else
	upl_control_flags = UPL_IOSYNC;
#endif
	if ((flags & SWAP_READ) == FALSE) {
		upl_create_flags |= UPL_COPYOUT_FROM;
	}
 
	upl_size = io_size;
	kr = vm_map_create_upl( kernel_map,
				start,
				&upl_size,
				&upl,
				NULL,
				&count,
				&upl_create_flags);

	if (kr != KERN_SUCCESS || (upl_size != io_size)) {
		panic("vm_map_create_upl failed with %d\n", kr);
	}

	if (flags & SWAP_READ) {
		vnode_pagein(vp,
			      upl,
			      0,
			      offset,
			      io_size,
			      upl_control_flags | UPL_IGNORE_VALID_PAGE_CHECK,
			      &error);
		if (error) {
#if DEBUG
			printf("vm_swapfile_io: vnode_pagein failed with %d (vp: %p, offset: 0x%llx, size:%llu)\n", error, vp, offset, io_size);
#else /* DEBUG */
			printf("vm_swapfile_io: vnode_pagein failed with %d.\n", error);
#endif /* DEBUG */
		}
	
	} else {
		vnode_pageout(vp,
			      upl,
			      0,
			      offset,
			      io_size,
			      upl_control_flags,
			      &error);
		if (error) {
#if DEBUG
			printf("vm_swapfile_io: vnode_pageout failed with %d (vp: %p, offset: 0x%llx, size:%llu)\n", error, vp, offset, io_size);
#else /* DEBUG */
			printf("vm_swapfile_io: vnode_pageout failed with %d.\n", error);
#endif /* DEBUG */
		}
	}
	return error;

#else /* 1 */
	vfs_context_t ctx;
	ctx = vfs_context_kernel();
		
	error = vn_rdwr((flags & SWAP_READ) ? UIO_READ : UIO_WRITE, vp, (caddr_t)start, io_size, offset,
		UIO_SYSSPACE, IO_SYNC | IO_NODELOCKED | IO_UNIT | IO_NOCACHE | IO_SWAP_DISPATCH, vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx));

	if (error) {
		printf("vn_rdwr: Swap I/O failed with %d\n", error);
	}
	return error;
#endif /* 1 */
}


#define MAX_BATCH_TO_TRIM	256

#define ROUTE_ONLY		0x10		/* if corestorage is present, tell it to just pass */
                                                /* the DKIOUNMAP command through w/o acting on it */
                                                /* this is used by the compressed swap system to reclaim empty space */


u_int32_t vnode_trim_list (vnode_t vp, struct trim_list *tl, boolean_t route_only)
{
	int		error = 0;
	int		trim_index = 0;
	u_int32_t	blocksize = 0;
	struct vnode	*devvp;
	dk_extent_t	*extents;
	dk_unmap_t	unmap;
	_dk_cs_unmap_t	cs_unmap;

	if ( !(vp->v_mount->mnt_ioflags & MNT_IOFLAGS_UNMAP_SUPPORTED))
		return (ENOTSUP);

	if (tl == NULL)
		return (0);

	/*
	 * Get the underlying device vnode and physical block size
	 */
	devvp = vp->v_mount->mnt_devvp;
	blocksize = vp->v_mount->mnt_devblocksize;

	extents = kalloc(sizeof(dk_extent_t) * MAX_BATCH_TO_TRIM);

	if (vp->v_mount->mnt_ioflags & MNT_IOFLAGS_CSUNMAP_SUPPORTED) {
		memset (&cs_unmap, 0, sizeof(_dk_cs_unmap_t));
		cs_unmap.extents = extents;

		if (route_only == TRUE)
			cs_unmap.options = ROUTE_ONLY;
	} else {
		memset (&unmap, 0, sizeof(dk_unmap_t));
		unmap.extents = extents;
	}

	while (tl) {
		daddr64_t	io_blockno;	/* Block number corresponding to the start of the extent */
		size_t		io_bytecount;	/* Number of bytes in current extent for the specified range */
		size_t		trimmed;
		size_t		remaining_length;
		off_t		current_offset; 

		current_offset = tl->tl_offset;
		remaining_length = tl->tl_length;
		trimmed = 0;
		
		/* 
		 * We may not get the entire range from tl_offset -> tl_offset+tl_length in a single
		 * extent from the blockmap call.  Keep looping/going until we are sure we've hit
		 * the whole range or if we encounter an error.
		 */
		while (trimmed < tl->tl_length) {
			/*
			 * VNOP_BLOCKMAP will tell us the logical to physical block number mapping for the
			 * specified offset.  It returns blocks in contiguous chunks, so if the logical range is 
			 * broken into multiple extents, it must be called multiple times, increasing the offset
			 * in each call to ensure that the entire range is covered.
			 */
			error = VNOP_BLOCKMAP (vp, current_offset, remaining_length, 
					       &io_blockno, &io_bytecount, NULL, VNODE_READ, NULL);

			if (error) {
				goto trim_exit;
			}

			extents[trim_index].offset = (uint64_t) io_blockno * (u_int64_t) blocksize;
			extents[trim_index].length = io_bytecount;

			trim_index++;

			if (trim_index == MAX_BATCH_TO_TRIM) {

				if (vp->v_mount->mnt_ioflags & MNT_IOFLAGS_CSUNMAP_SUPPORTED) {
					cs_unmap.extentsCount = trim_index;
					error = VNOP_IOCTL(devvp, _DKIOCCSUNMAP, (caddr_t)&cs_unmap, 0, vfs_context_kernel());
				} else {
					unmap.extentsCount = trim_index;
					error = VNOP_IOCTL(devvp, DKIOCUNMAP, (caddr_t)&unmap, 0, vfs_context_kernel());
				}
				if (error) {
					goto trim_exit;
				}
				trim_index = 0;
			}
			trimmed += io_bytecount;
			current_offset += io_bytecount;
			remaining_length -= io_bytecount;
		}
		tl = tl->tl_next;
	}
	if (trim_index) {
		if (vp->v_mount->mnt_ioflags & MNT_IOFLAGS_CSUNMAP_SUPPORTED) {
			cs_unmap.extentsCount = trim_index;
			error = VNOP_IOCTL(devvp, _DKIOCCSUNMAP, (caddr_t)&cs_unmap, 0, vfs_context_kernel());
		} else {
			unmap.extentsCount = trim_index;
			error = VNOP_IOCTL(devvp, DKIOCUNMAP, (caddr_t)&unmap, 0, vfs_context_kernel());
		}
	}
trim_exit:
	kfree(extents, sizeof(dk_extent_t) * MAX_BATCH_TO_TRIM);

	return error;
}
Commit	Line	Data
39236c6e A	1	/*
	2	* Copyright (c) 2000-2013 Apple Inc. All rights reserved.
	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*/
	28
	29	#include <stdint.h>
	30	#include <sys/fcntl.h>
	31	#include <sys/vnode_internal.h>
	32	#include <sys/vnode.h>
	33	#include <sys/kauth.h>
	34	#include <sys/mount_internal.h>
	35	#include <sys/buf_internal.h>
	36	#include <kern/debug.h>
	37	#include <kern/kalloc.h>
	38	#include <sys/cprotect.h>
	39	#include <sys/disk.h>
	40	#include <vm/vm_protos.h>
	41	#include <vm/vm_pageout.h>
	42
	43	void vm_swapfile_open(const char path, vnode_t vp);
	44	void vm_swapfile_close(uint64_t path, vnode_t vp);
3e170ce0	45	int vm_swapfile_preallocate(vnode_t vp, uint64_t size, boolean_t pin);
39236c6e A	46	uint64_t vm_swapfile_get_blksize(vnode_t vp);
	47	uint64_t vm_swapfile_get_transfer_size(vnode_t vp);
	48	int vm_swapfile_io(vnode_t vp, uint64_t offset, uint64_t start, int npages, int flags);
3e170ce0 A	49	int vm_record_file_write(struct vnode vp, uint64_t offset, char buf, int size);
3e170ce0 A	50
39236c6e A	51
	52	void
	53	vm_swapfile_open(const char path, vnode_t vp)
	54	{
	55	int error = 0;
	56	vfs_context_t ctx = vfs_context_current();
	57
fe8ab488	58	if ((error = vnode_open(path, (O_CREAT \| O_TRUNC \| FREAD \| FWRITE), S_IRUSR \| S_IWUSR, 0, vp, ctx))) {
39236c6e A	59	printf("Failed to open swap file %d\n", error);
	60	*vp = NULL;
	61	return;
	62	}
	63
	64	vnode_put(*vp);
	65	}
	66
	67	uint64_t
	68	vm_swapfile_get_blksize(vnode_t vp)
	69	{
	70	return ((uint64_t)vfs_devblocksize(vnode_mount(vp)));
	71	}
	72
	73	uint64_t
	74	vm_swapfile_get_transfer_size(vnode_t vp)
	75	{
	76	return((uint64_t)vp->v_mount->mnt_vfsstat.f_iosize);
	77	}
	78
c18c124e	79	int unlink1(vfs_context_t, vnode_t, user_addr_t, enum uio_seg, int);
39236c6e A	80
	81	void
	82	vm_swapfile_close(uint64_t path_addr, vnode_t vp)
	83	{
39236c6e	84	vfs_context_t context = vfs_context_current();
c18c124e	85	int error;
39236c6e A	86
	87	vnode_getwithref(vp);
	88	vnode_close(vp, 0, context);
	89
c18c124e A	90	error = unlink1(context, NULLVP, CAST_USER_ADDR_T(path_addr),
c18c124e A	91	UIO_SYSSPACE, 0);
39236c6e	92
c18c124e A	93	#if DEVELOPMENT \|\| DEBUG
	94	if (error)
	95	printf("%s : unlink of %s failed with error %d", __FUNCTION__,
	96	(char *)path_addr, error);
	97	#endif
39236c6e A	98	}
	99
	100	int
3e170ce0	101	vm_swapfile_preallocate(vnode_t vp, uint64_t size, boolean_t pin)
39236c6e A	102	{
	103	int error = 0;
	104	uint64_t file_size = 0;
	105	vfs_context_t ctx = NULL;
	106
	107
	108	ctx = vfs_context_current();
	109
fe8ab488	110	error = vnode_setsize(vp, *size, IO_NOZEROFILL, ctx);
39236c6e	111
fe8ab488 A	112	if (error) {
fe8ab488 A	113	printf("vnode_setsize for swap files failed: %d\n", error);
39236c6e	114	goto done;
fe8ab488	115	}
39236c6e	116
fe8ab488	117	error = vnode_size(vp, (off_t*) &file_size, ctx);
39236c6e	118
fe8ab488 A	119	if (error) {
fe8ab488 A	120	printf("vnode_size (new file) for swap file failed: %d\n", error);
3e170ce0	121	goto done;
fe8ab488	122	}
fe8ab488 A	123	assert(file_size == *size);
fe8ab488 A	124
3e170ce0	125	if (pin != NULL && *pin != FALSE) {
39037602	126	error = VNOP_IOCTL(vp, FIOPINSWAP, NULL, 0, ctx);
3e170ce0 A	127
3e170ce0 A	128	if (error) {
39037602	129	printf("pin for swap files failed: %d, file_size = %lld\n", error, file_size);
3e170ce0 A	130	/* this is not fatal, carry on with files wherever they landed */
	131	*pin = FALSE;
	132	error = 0;
	133	}
	134	}
	135
39236c6e A	136	vnode_lock_spin(vp);
	137	SET(vp->v_flag, VSWAP);
	138	vnode_unlock(vp);
	139	done:
	140	return error;
	141	}
	142
3e170ce0 A	143
	144	int
	145	vm_record_file_write(vnode_t vp, uint64_t offset, char *buf, int size)
	146	{
	147	int error = 0;
	148	vfs_context_t ctx;
	149
	150	ctx = vfs_context_kernel();
	151
	152	error = vn_rdwr(UIO_WRITE, vp, (caddr_t)buf, size, offset,
	153	UIO_SYSSPACE, IO_NODELOCKED, vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx));
	154
	155	return (error);
	156	}
	157
	158
	159
39236c6e A	160	int
	161	vm_swapfile_io(vnode_t vp, uint64_t offset, uint64_t start, int npages, int flags)
	162	{
	163	int error = 0;
	164	uint64_t io_size = npages * PAGE_SIZE_64;
	165	#if 1
	166	kern_return_t kr = KERN_SUCCESS;
	167	upl_t upl = NULL;
	168	unsigned int count = 0;
3e170ce0 A	169	upl_control_flags_t upl_create_flags = 0;
3e170ce0 A	170	int upl_control_flags = 0;
39236c6e A	171	upl_size_t upl_size = 0;
39236c6e A	172
3e170ce0 A	173	upl_create_flags = UPL_SET_INTERNAL \| UPL_SET_LITE
3e170ce0 A	174	\| UPL_MEMORY_TAG_MAKE(VM_KERN_MEMORY_OSFMK);
39236c6e	175
fe8ab488 A	176	#if ENCRYPTED_SWAP
	177	upl_control_flags = UPL_IOSYNC \| UPL_PAGING_ENCRYPTED;
	178	#else
	179	upl_control_flags = UPL_IOSYNC;
	180	#endif
39236c6e A	181	if ((flags & SWAP_READ) == FALSE) {
	182	upl_create_flags \|= UPL_COPYOUT_FROM;
	183	}
	184
	185	upl_size = io_size;
	186	kr = vm_map_create_upl( kernel_map,
	187	start,
	188	&upl_size,
	189	&upl,
	190	NULL,
	191	&count,
	192	&upl_create_flags);
	193
	194	if (kr != KERN_SUCCESS \|\| (upl_size != io_size)) {
	195	panic("vm_map_create_upl failed with %d\n", kr);
	196	}
	197
	198	if (flags & SWAP_READ) {
	199	vnode_pagein(vp,
	200	upl,
	201	0,
	202	offset,
	203	io_size,
	204	upl_control_flags \| UPL_IGNORE_VALID_PAGE_CHECK,
	205	&error);
	206	if (error) {
	207	#if DEBUG
	208	printf("vm_swapfile_io: vnode_pagein failed with %d (vp: %p, offset: 0x%llx, size:%llu)\n", error, vp, offset, io_size);
	209	#else /* DEBUG */
	210	printf("vm_swapfile_io: vnode_pagein failed with %d.\n", error);
	211	#endif /* DEBUG */
	212	}
	213
	214	} else {
	215	vnode_pageout(vp,
	216	upl,
	217	0,
	218	offset,
	219	io_size,
	220	upl_control_flags,
	221	&error);
	222	if (error) {
	223	#if DEBUG
	224	printf("vm_swapfile_io: vnode_pageout failed with %d (vp: %p, offset: 0x%llx, size:%llu)\n", error, vp, offset, io_size);
	225	#else /* DEBUG */
	226	printf("vm_swapfile_io: vnode_pageout failed with %d.\n", error);
	227	#endif /* DEBUG */
	228	}
	229	}
	230	return error;
	231
	232	#else /* 1 */
	233	vfs_context_t ctx;
	234	ctx = vfs_context_kernel();
	235
	236	error = vn_rdwr((flags & SWAP_READ) ? UIO_READ : UIO_WRITE, vp, (caddr_t)start, io_size, offset,
	237	UIO_SYSSPACE, IO_SYNC \| IO_NODELOCKED \| IO_UNIT \| IO_NOCACHE \| IO_SWAP_DISPATCH, vfs_context_ucred(ctx), (int *) 0, vfs_context_proc(ctx));
	238
	239	if (error) {
	240	printf("vn_rdwr: Swap I/O failed with %d\n", error);
	241	}
	242	return error;
	243	#endif /* 1 */
	244	}
245
246
247	#define MAX_BATCH_TO_TRIM 256
248
fe8ab488 A	249	#define ROUTE_ONLY 0x10 /* if corestorage is present, tell it to just pass */
	250	/* the DKIOUNMAP command through w/o acting on it */
	251	/* this is used by the compressed swap system to reclaim empty space */
	252
	253
	254	u_int32_t vnode_trim_list (vnode_t vp, struct trim_list *tl, boolean_t route_only)
39236c6e A	255	{
	256	int error = 0;
	257	int trim_index = 0;
	258	u_int32_t blocksize = 0;
	259	struct vnode *devvp;
	260	dk_extent_t *extents;
	261	dk_unmap_t unmap;
fe8ab488	262	_dk_cs_unmap_t cs_unmap;
39236c6e A	263
	264	if ( !(vp->v_mount->mnt_ioflags & MNT_IOFLAGS_UNMAP_SUPPORTED))
	265	return (ENOTSUP);
	266
	267	if (tl == NULL)
	268	return (0);
	269
	270	/*
	271	* Get the underlying device vnode and physical block size
	272	*/
	273	devvp = vp->v_mount->mnt_devvp;
	274	blocksize = vp->v_mount->mnt_devblocksize;
	275
	276	extents = kalloc(sizeof(dk_extent_t) * MAX_BATCH_TO_TRIM);
	277
fe8ab488 A	278	if (vp->v_mount->mnt_ioflags & MNT_IOFLAGS_CSUNMAP_SUPPORTED) {
	279	memset (&cs_unmap, 0, sizeof(_dk_cs_unmap_t));
	280	cs_unmap.extents = extents;
	281
	282	if (route_only == TRUE)
	283	cs_unmap.options = ROUTE_ONLY;
	284	} else {
	285	memset (&unmap, 0, sizeof(dk_unmap_t));
	286	unmap.extents = extents;
	287	}
39236c6e A	288
	289	while (tl) {
	290	daddr64_t io_blockno; /* Block number corresponding to the start of the extent */
	291	size_t io_bytecount; /* Number of bytes in current extent for the specified range */
	292	size_t trimmed;
	293	size_t remaining_length;
	294	off_t current_offset;
	295
	296	current_offset = tl->tl_offset;
	297	remaining_length = tl->tl_length;
	298	trimmed = 0;
	299
	300	/*
	301	* We may not get the entire range from tl_offset -> tl_offset+tl_length in a single
	302	* extent from the blockmap call. Keep looping/going until we are sure we've hit
	303	* the whole range or if we encounter an error.
	304	*/
	305	while (trimmed < tl->tl_length) {
	306	/*
	307	* VNOP_BLOCKMAP will tell us the logical to physical block number mapping for the
	308	* specified offset. It returns blocks in contiguous chunks, so if the logical range is
	309	* broken into multiple extents, it must be called multiple times, increasing the offset
	310	* in each call to ensure that the entire range is covered.
	311	*/
	312	error = VNOP_BLOCKMAP (vp, current_offset, remaining_length,
	313	&io_blockno, &io_bytecount, NULL, VNODE_READ, NULL);
	314
	315	if (error) {
	316	goto trim_exit;
	317	}
	318
	319	extents[trim_index].offset = (uint64_t) io_blockno * (u_int64_t) blocksize;
	320	extents[trim_index].length = io_bytecount;
	321
	322	trim_index++;
	323
	324	if (trim_index == MAX_BATCH_TO_TRIM) {
	325
fe8ab488 A	326	if (vp->v_mount->mnt_ioflags & MNT_IOFLAGS_CSUNMAP_SUPPORTED) {
	327	cs_unmap.extentsCount = trim_index;
	328	error = VNOP_IOCTL(devvp, _DKIOCCSUNMAP, (caddr_t)&cs_unmap, 0, vfs_context_kernel());
	329	} else {
	330	unmap.extentsCount = trim_index;
	331	error = VNOP_IOCTL(devvp, DKIOCUNMAP, (caddr_t)&unmap, 0, vfs_context_kernel());
	332	}
39236c6e A	333	if (error) {
	334	goto trim_exit;
	335	}
	336	trim_index = 0;
	337	}
	338	trimmed += io_bytecount;
	339	current_offset += io_bytecount;
	340	remaining_length -= io_bytecount;
	341	}
	342	tl = tl->tl_next;
	343	}
	344	if (trim_index) {
fe8ab488 A	345	if (vp->v_mount->mnt_ioflags & MNT_IOFLAGS_CSUNMAP_SUPPORTED) {
	346	cs_unmap.extentsCount = trim_index;
	347	error = VNOP_IOCTL(devvp, _DKIOCCSUNMAP, (caddr_t)&cs_unmap, 0, vfs_context_kernel());
	348	} else {
	349	unmap.extentsCount = trim_index;
	350	error = VNOP_IOCTL(devvp, DKIOCUNMAP, (caddr_t)&unmap, 0, vfs_context_kernel());
	351	}
39236c6e A	352	}
	353	trim_exit:
	354	kfree(extents, sizeof(dk_extent_t) * MAX_BATCH_TO_TRIM);
	355
	356	return error;
	357	}