Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 174 insertions, 0 deletions

diff --git a/fs/btrfs/accessors.c b/fs/btrfs/accessors.c
new file mode 100644
index 0000000000..206cf1612c
--- /dev/null
+++ b/fs/btrfs/accessors.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2007 Oracle.  All rights reserved.
+ */
+
+#include <asm/unaligned.h>
+#include "messages.h"
+#include "ctree.h"
+#include "accessors.h"
+
+static bool check_setget_bounds(const struct extent_buffer *eb,
+				const void *ptr, unsigned off, int size)
+{
+	const unsigned long member_offset = (unsigned long)ptr + off;
+
+	if (unlikely(member_offset + size > eb->len)) {
+		btrfs_warn(eb->fs_info,
+		"bad eb member %s: ptr 0x%lx start %llu member offset %lu size %d",
+			(member_offset > eb->len ? "start" : "end"),
+			(unsigned long)ptr, eb->start, member_offset, size);
+		return false;
+	}
+
+	return true;
+}
+
+void btrfs_init_map_token(struct btrfs_map_token *token, struct extent_buffer *eb)
+{
+	token->eb = eb;
+	token->kaddr = page_address(eb->pages[0]);
+	token->offset = 0;
+}
+
+/*
+ * Macro templates that define helpers to read/write extent buffer data of a
+ * given size, that are also used via ctree.h for access to item members by
+ * specialized helpers.
+ *
+ * Generic helpers:
+ * - btrfs_set_8 (for 8/16/32/64)
+ * - btrfs_get_8 (for 8/16/32/64)
+ *
+ * Generic helpers with a token (cached address of the most recently accessed
+ * page):
+ * - btrfs_set_token_8 (for 8/16/32/64)
+ * - btrfs_get_token_8 (for 8/16/32/64)
+ *
+ * The set/get functions handle data spanning two pages transparently, in case
+ * metadata block size is larger than page.  Every pointer to metadata items is
+ * an offset into the extent buffer page array, cast to a specific type.  This
+ * gives us all the type checking.
+ *
+ * The extent buffer pages stored in the array pages do not form a contiguous
+ * phyusical range, but the API functions assume the linear offset to the range
+ * from 0 to metadata node size.
+ */
+
+#define DEFINE_BTRFS_SETGET_BITS(bits)					\
+u##bits btrfs_get_token_##bits(struct btrfs_map_token *token,		\
+			       const void *ptr, unsigned long off)	\
+{									\
+	const unsigned long member_offset = (unsigned long)ptr + off;	\
+	const unsigned long idx = get_eb_page_index(member_offset);	\
+	const unsigned long oip = get_eb_offset_in_page(token->eb,	\
+							member_offset);	\
+	const int size = sizeof(u##bits);				\
+	u8 lebytes[sizeof(u##bits)];					\
+	const int part = PAGE_SIZE - oip;				\
+									\
+	ASSERT(token);							\
+	ASSERT(token->kaddr);						\
+	ASSERT(check_setget_bounds(token->eb, ptr, off, size));		\
+	if (token->offset <= member_offset &&				\
+	    member_offset + size <= token->offset + PAGE_SIZE) {	\
+		return get_unaligned_le##bits(token->kaddr + oip);	\
+	}								\
+	token->kaddr = page_address(token->eb->pages[idx]);		\
+	token->offset = idx << PAGE_SHIFT;				\
+	if (INLINE_EXTENT_BUFFER_PAGES == 1 || oip + size <= PAGE_SIZE ) \
+		return get_unaligned_le##bits(token->kaddr + oip);	\
+									\
+	memcpy(lebytes, token->kaddr + oip, part);			\
+	token->kaddr = page_address(token->eb->pages[idx + 1]);		\
+	token->offset = (idx + 1) << PAGE_SHIFT;			\
+	memcpy(lebytes + part, token->kaddr, size - part);		\
+	return get_unaligned_le##bits(lebytes);				\
+}									\
+u##bits btrfs_get_##bits(const struct extent_buffer *eb,		\
+			 const void *ptr, unsigned long off)		\
+{									\
+	const unsigned long member_offset = (unsigned long)ptr + off;	\
+	const unsigned long oip = get_eb_offset_in_page(eb, member_offset); \
+	const unsigned long idx = get_eb_page_index(member_offset);	\
+	char *kaddr = page_address(eb->pages[idx]);			\
+	const int size = sizeof(u##bits);				\
+	const int part = PAGE_SIZE - oip;				\
+	u8 lebytes[sizeof(u##bits)];					\
+									\
+	ASSERT(check_setget_bounds(eb, ptr, off, size));		\
+	if (INLINE_EXTENT_BUFFER_PAGES == 1 || oip + size <= PAGE_SIZE)	\
+		return get_unaligned_le##bits(kaddr + oip);		\
+									\
+	memcpy(lebytes, kaddr + oip, part);				\
+	kaddr = page_address(eb->pages[idx + 1]);			\
+	memcpy(lebytes + part, kaddr, size - part);			\
+	return get_unaligned_le##bits(lebytes);				\
+}									\
+void btrfs_set_token_##bits(struct btrfs_map_token *token,		\
+			    const void *ptr, unsigned long off,		\
+			    u##bits val)				\
+{									\
+	const unsigned long member_offset = (unsigned long)ptr + off;	\
+	const unsigned long idx = get_eb_page_index(member_offset);	\
+	const unsigned long oip = get_eb_offset_in_page(token->eb,	\
+							member_offset);	\
+	const int size = sizeof(u##bits);				\
+	u8 lebytes[sizeof(u##bits)];					\
+	const int part = PAGE_SIZE - oip;				\
+									\
+	ASSERT(token);							\
+	ASSERT(token->kaddr);						\
+	ASSERT(check_setget_bounds(token->eb, ptr, off, size));		\
+	if (token->offset <= member_offset &&				\
+	    member_offset + size <= token->offset + PAGE_SIZE) {	\
+		put_unaligned_le##bits(val, token->kaddr + oip);	\
+		return;							\
+	}								\
+	token->kaddr = page_address(token->eb->pages[idx]);		\
+	token->offset = idx << PAGE_SHIFT;				\
+	if (INLINE_EXTENT_BUFFER_PAGES == 1 || oip + size <= PAGE_SIZE) { \
+		put_unaligned_le##bits(val, token->kaddr + oip);	\
+		return;							\
+	}								\
+	put_unaligned_le##bits(val, lebytes);				\
+	memcpy(token->kaddr + oip, lebytes, part);			\
+	token->kaddr = page_address(token->eb->pages[idx + 1]);		\
+	token->offset = (idx + 1) << PAGE_SHIFT;			\
+	memcpy(token->kaddr, lebytes + part, size - part);		\
+}									\
+void btrfs_set_##bits(const struct extent_buffer *eb, void *ptr,	\
+		      unsigned long off, u##bits val)			\
+{									\
+	const unsigned long member_offset = (unsigned long)ptr + off;	\
+	const unsigned long oip = get_eb_offset_in_page(eb, member_offset); \
+	const unsigned long idx = get_eb_page_index(member_offset);	\
+	char *kaddr = page_address(eb->pages[idx]);			\
+	const int size = sizeof(u##bits);				\
+	const int part = PAGE_SIZE - oip;				\
+	u8 lebytes[sizeof(u##bits)];					\
+									\
+	ASSERT(check_setget_bounds(eb, ptr, off, size));		\
+	if (INLINE_EXTENT_BUFFER_PAGES == 1 || oip + size <= PAGE_SIZE) { \
+		put_unaligned_le##bits(val, kaddr + oip);		\
+		return;							\
+	}								\
+									\
+	put_unaligned_le##bits(val, lebytes);				\
+	memcpy(kaddr + oip, lebytes, part);				\
+	kaddr = page_address(eb->pages[idx + 1]);			\
+	memcpy(kaddr, lebytes + part, size - part);			\
+}
+
+DEFINE_BTRFS_SETGET_BITS(8)
+DEFINE_BTRFS_SETGET_BITS(16)
+DEFINE_BTRFS_SETGET_BITS(32)
+DEFINE_BTRFS_SETGET_BITS(64)
+
+void btrfs_node_key(const struct extent_buffer *eb,
+		    struct btrfs_disk_key *disk_key, int nr)
+{
+	unsigned long ptr = btrfs_node_key_ptr_offset(eb, nr);
+	read_eb_member(eb, (struct btrfs_key_ptr *)ptr,
+		       struct btrfs_key_ptr, key, disk_key);
+}