/* * Copyright (C) 2007 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License v2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #include #include #include "ctree.h" static inline u8 get_unaligned_le8(const void *p) { return *(u8 *)p; } static inline void put_unaligned_le8(u8 val, void *p) { *(u8 *)p = val; } /* * this is some deeply nasty code. * * The end result is that anyone who #includes ctree.h gets a * declaration for the btrfs_set_foo functions and btrfs_foo functions, * which are wrappers of btrfs_set_token_#bits functions and * btrfs_get_token_#bits functions, which are defined in this file. * * These setget functions do all the extent_buffer related mapping * required to efficiently read and write specific fields in the extent * buffers. Every pointer to metadata items in btrfs is really just * an unsigned long offset into the extent buffer which has been * cast to a specific type. This gives us all the gcc type checking. * * The extent buffer api is used to do the page spanning work required to * have a metadata blocksize different from the page size. */ #define DEFINE_BTRFS_SETGET_BITS(bits) \ u##bits btrfs_get_token_##bits(struct extent_buffer *eb, void *ptr, \ unsigned long off, \ struct btrfs_map_token *token) \ { \ unsigned long part_offset = (unsigned long)ptr; \ unsigned long offset = part_offset + off; \ void *p; \ int err; \ char *kaddr; \ unsigned long map_start; \ unsigned long map_len; \ int size = sizeof(u##bits); \ u##bits res; \ \ if (token && token->kaddr && token->offset <= offset && \ token->eb == eb && \ (token->offset + PAGE_SIZE >= offset + size)) { \ kaddr = token->kaddr; \ p = kaddr + part_offset - token->offset; \ res = get_unaligned_le##bits(p + off); \ return res; \ } \ err = map_private_extent_buffer(eb, offset, size, \ &kaddr, &map_start, &map_len); \ if (err) { \ __le##bits leres; \ \ read_extent_buffer(eb, &leres, offset, size); \ return le##bits##_to_cpu(leres); \ } \ p = kaddr + part_offset - map_start; \ res = get_unaligned_le##bits(p + off); \ if (token) { \ token->kaddr = kaddr; \ token->offset = map_start; \ token->eb = eb; \ } \ return res; \ } \ void btrfs_set_token_##bits(struct extent_buffer *eb, \ void *ptr, unsigned long off, u##bits val, \ struct btrfs_map_token *token) \ { \ unsigned long part_offset = (unsigned long)ptr; \ unsigned long offset = part_offset + off; \ void *p; \ int err; \ char *kaddr; \ unsigned long map_start; \ unsigned long map_len; \ int size = sizeof(u##bits); \ \ if (token && token->kaddr && token->offset <= offset && \ token->eb == eb && \ (token->offset + PAGE_SIZE >= offset + size)) { \ kaddr = token->kaddr; \ p = kaddr + part_offset - token->offset; \ put_unaligned_le##bits(val, p + off); \ return; \ } \ err = map_private_extent_buffer(eb, offset, size, \ &kaddr, &map_start, &map_len); \ if (err) { \ __le##bits val2; \ \ val2 = cpu_to_le##bits(val); \ write_extent_buffer(eb, &val2, offset, size); \ return; \ } \ p = kaddr + part_offset - map_start; \ put_unaligned_le##bits(val, p + off); \ if (token) { \ token->kaddr = kaddr; \ token->offset = map_start; \ token->eb = eb; \ } \ } DEFINE_BTRFS_SETGET_BITS(8) DEFINE_BTRFS_SETGET_BITS(16) DEFINE_BTRFS_SETGET_BITS(32) DEFINE_BTRFS_SETGET_BITS(64) void btrfs_node_key(struct extent_buffer *eb, struct btrfs_disk_key *disk_key, int nr) { unsigned long ptr = btrfs_node_key_ptr_offset(nr); read_eb_member(eb, (struct btrfs_key_ptr *)ptr, struct btrfs_key_ptr, key, disk_key); } ion value='1'>ssdiff
authorLinus Torvalds <torvalds@linux-foundation.org>2016-12-30 09:32:26 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-30 09:32:26 -0800
commit238d1d0f79f619d75c2cc741d6770fb0986aef24 (patch)
treeed11bb89c3c61cba7aff3ebc90647f83758a982d /include/dt-bindings/clock/imx6qdl-clock.h
parentf3de082c12e5e9ff43c58a7561f6ec3272d03a48 (diff)
parent36f671be1db1b17d3d4ab0c8b47f81ccb1efcb75 (diff)
Merge tag 'docs-4.10-rc1-fix' of git://git.lwn.net/linux
Pull documentation fixes from Jonathan Corbet: "Two small fixes: - A merge error on my part broke the DocBook build. I've requisitioned one of tglx's frozen sharks for appropriate disciplinary action and resolved to be more careful about testing the DocBook stuff as long as it's still around. - Fix an error in unaligned-memory-access.txt" * tag 'docs-4.10-rc1-fix' of git://git.lwn.net/linux: Documentation/unaligned-memory-access.txt: fix incorrect comparison operator docs: Fix build failure
Diffstat (limited to 'include/dt-bindings/clock/imx6qdl-clock.h')