diff options
Diffstat (limited to 'include/sys/abd.h')
| -rw-r--r-- | include/sys/abd.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/include/sys/abd.h b/include/sys/abd.h new file mode 100644 index 000000000..43aaa7a15 --- /dev/null +++ b/include/sys/abd.h @@ -0,0 +1,160 @@ +/* + * 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) 2014 by Chunwei Chen. All rights reserved. + * Copyright (c) 2016 by Delphix. All rights reserved. + */ + +#ifndef _ABD_H +#define _ABD_H + +#include <sys/isa_defs.h> +#include <sys/int_types.h> +#include <sys/debug.h> +#include <sys/refcount.h> +#ifdef _KERNEL +#include <linux/mm.h> +#include <sys/uio.h> +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +typedef enum abd_flags { + ABD_FLAG_LINEAR = 1 << 0, /* is buffer linear (or scattered)? */ + ABD_FLAG_OWNER = 1 << 1, /* does it own its data buffers? */ + ABD_FLAG_META = 1 << 2 /* does this represent FS metadata? */ +} abd_flags_t; + +typedef struct abd { + abd_flags_t abd_flags; + uint_t abd_size; /* excludes scattered abd_offset */ + struct abd *abd_parent; + refcount_t abd_children; + union { + struct abd_scatter { + uint_t abd_offset; + uint_t abd_chunk_size; + struct page *abd_chunks[]; + } abd_scatter; + struct abd_linear { + void *abd_buf; + } abd_linear; + } abd_u; +} abd_t; + +typedef int abd_iter_func_t(void *buf, size_t len, void *private); +typedef int abd_iter_func2_t(void *bufa, void *bufb, size_t len, void *private); + +extern int zfs_abd_scatter_enabled; + +static inline boolean_t +abd_is_linear(abd_t *abd) +{ + return ((abd->abd_flags & ABD_FLAG_LINEAR) != 0); +} + +/* + * Allocations and deallocations + */ + +abd_t *abd_alloc(size_t, boolean_t); +abd_t *abd_alloc_linear(size_t, boolean_t); +abd_t *abd_alloc_for_io(size_t, boolean_t); +abd_t *abd_alloc_sametype(abd_t *, size_t); +void abd_free(abd_t *); +abd_t *abd_get_offset(abd_t *, size_t); +abd_t *abd_get_from_buf(void *, size_t); +void abd_put(abd_t *); + +/* + * Conversion to and from a normal buffer + */ + +void *abd_to_buf(abd_t *); +void *abd_borrow_buf(abd_t *, size_t); +void *abd_borrow_buf_copy(abd_t *, size_t); +void abd_return_buf(abd_t *, void *, size_t); +void abd_return_buf_copy(abd_t *, void *, size_t); +void abd_take_ownership_of_buf(abd_t *, boolean_t); +void abd_release_ownership_of_buf(abd_t *); + +/* + * ABD operations + */ + +int abd_iterate_func(abd_t *, size_t, size_t, abd_iter_func_t *, void *); +int abd_iterate_func2(abd_t *, abd_t *, size_t, size_t, size_t, + abd_iter_func2_t *, void *); +void abd_copy_off(abd_t *, abd_t *, size_t, size_t, size_t); +void abd_copy_from_buf_off(abd_t *, const void *, size_t, size_t); +void abd_copy_to_buf_off(void *, abd_t *, size_t, size_t); +int abd_cmp(abd_t *, abd_t *); +int abd_cmp_buf_off(abd_t *, const void *, size_t, size_t); +void abd_zero_off(abd_t *, size_t, size_t); + +/* + * Wrappers for calls with offsets of 0 + */ + +static inline void +abd_copy(abd_t *dabd, abd_t *sabd, size_t size) +{ + abd_copy_off(dabd, sabd, 0, 0, size); +} + +static inline void +abd_copy_from_buf(abd_t *abd, void *buf, size_t size) +{ + abd_copy_from_buf_off(abd, buf, 0, size); +} + +static inline void +abd_copy_to_buf(void* buf, abd_t *abd, size_t size) +{ + abd_copy_to_buf_off(buf, abd, 0, size); +} + +static inline int +abd_cmp_buf(abd_t *abd, void *buf, size_t size) +{ + return (abd_cmp_buf_off(abd, buf, 0, size)); +} + +static inline void +abd_zero(abd_t *abd, size_t size) +{ + abd_zero_off(abd, 0, size); +} + +/* + * Module lifecycle + */ + +void abd_init(void); +void abd_fini(void); + +#ifdef __cplusplus +} +#endif + +#endif /* _ABD_H */ |