[B][PATCH 1/7] btrfs: use offset_in_page instead of open-coding it
Mauricio Faria de Oliveira
mfo at canonical.com
Fri Oct 30 15:27:52 UTC 2020
From: Johannes Thumshirn <jthumshirn at suse.de>
BugLink: https://bugs.launchpad.net/bugs/1902254
Constructs like 'var & (PAGE_SIZE - 1)' or 'var & ~PAGE_MASK' can denote an
offset into a page.
So replace them by the offset_in_page() macro instead of open-coding it if
they're not used as an alignment check.
Reviewed-by: Nikolay Borisov <nborisov at suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn at suse.de>
Reviewed-by: David Sterba <dsterba at suse.com>
Signed-off-by: David Sterba <dsterba at suse.com>
(backported from commit 7073017aeb98db311ca407f0f552f2bfc1af3015)
[mfo: backport: refresh context lines in extent_io.c:hunk 7/file.c:hunk 2]
Signed-off-by: Mauricio Faria de Oliveira <mfo at canonical.com>
---
fs/btrfs/check-integrity.c | 12 ++++-----
fs/btrfs/compression.c | 2 +-
fs/btrfs/extent_io.c | 53 +++++++++++++++++---------------------
fs/btrfs/file.c | 4 +--
fs/btrfs/inode.c | 7 +++--
fs/btrfs/send.c | 2 +-
fs/btrfs/volumes.c | 2 +-
7 files changed, 38 insertions(+), 44 deletions(-)
diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index 9336fd23c1d5..6d75f5322cd0 100644
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -1214,24 +1214,24 @@ static void btrfsic_read_from_block_data(
void *dstv, u32 offset, size_t len)
{
size_t cur;
- size_t offset_in_page;
+ size_t pgoff;
char *kaddr;
char *dst = (char *)dstv;
- size_t start_offset = block_ctx->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(block_ctx->start);
unsigned long i = (start_offset + offset) >> PAGE_SHIFT;
WARN_ON(offset + len > block_ctx->len);
- offset_in_page = (start_offset + offset) & (PAGE_SIZE - 1);
+ pgoff = offset_in_page(start_offset + offset);
while (len > 0) {
- cur = min(len, ((size_t)PAGE_SIZE - offset_in_page));
+ cur = min(len, ((size_t)PAGE_SIZE - pgoff));
BUG_ON(i >= DIV_ROUND_UP(block_ctx->len, PAGE_SIZE));
kaddr = block_ctx->datav[i];
- memcpy(dst, kaddr + offset_in_page, cur);
+ memcpy(dst, kaddr + pgoff, cur);
dst += cur;
len -= cur;
- offset_in_page = 0;
+ pgoff = 0;
i++;
}
}
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index a3dd9d39afbb..cdadf2e9b94d 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -526,7 +526,7 @@ static noinline int add_ra_bio_pages(struct inode *inode,
if (page->index == end_index) {
char *userpage;
- size_t zero_offset = isize & (PAGE_SIZE - 1);
+ size_t zero_offset = offset_in_page(isize);
if (zero_offset) {
int zeros;
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 77f5cd1346f8..1a70780cf2ee 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2671,7 +2671,7 @@ static void end_bio_extent_readpage(struct bio *bio)
unsigned off;
/* Zero out the end if this page straddles i_size */
- off = i_size & (PAGE_SIZE-1);
+ off = offset_in_page(i_size);
if (page->index == end_index && off)
zero_user_segment(page, off, PAGE_SIZE);
SetPageUptodate(page);
@@ -2951,7 +2951,7 @@ static int __do_readpage(struct extent_io_tree *tree,
if (page->index == last_byte >> PAGE_SHIFT) {
char *userpage;
- size_t zero_offset = last_byte & (PAGE_SIZE - 1);
+ size_t zero_offset = offset_in_page(last_byte);
if (zero_offset) {
iosize = PAGE_SIZE - zero_offset;
@@ -3513,7 +3513,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
ClearPageError(page);
- pg_offset = i_size & (PAGE_SIZE - 1);
+ pg_offset = offset_in_page(i_size);
if (page->index > end_index ||
(page->index == end_index && !pg_offset)) {
page->mapping->a_ops->invalidatepage(page, 0, PAGE_SIZE);
@@ -5464,7 +5464,7 @@ void read_extent_buffer(const struct extent_buffer *eb, void *dstv,
struct page *page;
char *kaddr;
char *dst = (char *)dstv;
- size_t start_offset = eb->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(eb->start);
unsigned long i = (start_offset + start) >> PAGE_SHIFT;
if (start + len > eb->len) {
@@ -5474,7 +5474,7 @@ void read_extent_buffer(const struct extent_buffer *eb, void *dstv,
return;
}
- offset = (start_offset + start) & (PAGE_SIZE - 1);
+ offset = offset_in_page(start_offset + start);
while (len > 0) {
page = eb->pages[i];
@@ -5499,14 +5499,14 @@ int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb,
struct page *page;
char *kaddr;
char __user *dst = (char __user *)dstv;
- size_t start_offset = eb->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(eb->start);
unsigned long i = (start_offset + start) >> PAGE_SHIFT;
int ret = 0;
WARN_ON(start > eb->len);
WARN_ON(start + len > eb->start + eb->len);
- offset = (start_offset + start) & (PAGE_SIZE - 1);
+ offset = offset_in_page(start_offset + start);
while (len > 0) {
page = eb->pages[i];
@@ -5540,7 +5540,7 @@ int map_private_extent_buffer(const struct extent_buffer *eb,
size_t offset = start & (PAGE_SIZE - 1);
char *kaddr;
struct page *p;
- size_t start_offset = eb->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(eb->start);
unsigned long i = (start_offset + start) >> PAGE_SHIFT;
unsigned long end_i = (start_offset + start + min_len - 1) >>
PAGE_SHIFT;
@@ -5577,14 +5577,14 @@ int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
struct page *page;
char *kaddr;
char *ptr = (char *)ptrv;
- size_t start_offset = eb->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(eb->start);
unsigned long i = (start_offset + start) >> PAGE_SHIFT;
int ret = 0;
WARN_ON(start > eb->len);
WARN_ON(start + len > eb->start + eb->len);
- offset = (start_offset + start) & (PAGE_SIZE - 1);
+ offset = offset_in_page(start_offset + start);
while (len > 0) {
page = eb->pages[i];
@@ -5633,13 +5633,13 @@ void write_extent_buffer(struct extent_buffer *eb, const void *srcv,
struct page *page;
char *kaddr;
char *src = (char *)srcv;
- size_t start_offset = eb->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(eb->start);
unsigned long i = (start_offset + start) >> PAGE_SHIFT;
WARN_ON(start > eb->len);
WARN_ON(start + len > eb->start + eb->len);
- offset = (start_offset + start) & (PAGE_SIZE - 1);
+ offset = offset_in_page(start_offset + start);
while (len > 0) {
page = eb->pages[i];
@@ -5663,13 +5663,13 @@ void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
size_t offset;
struct page *page;
char *kaddr;
- size_t start_offset = eb->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(eb->start);
unsigned long i = (start_offset + start) >> PAGE_SHIFT;
WARN_ON(start > eb->len);
WARN_ON(start + len > eb->start + eb->len);
- offset = (start_offset + start) & (PAGE_SIZE - 1);
+ offset = offset_in_page(start_offset + start);
while (len > 0) {
page = eb->pages[i];
@@ -5708,13 +5708,12 @@ void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
size_t offset;
struct page *page;
char *kaddr;
- size_t start_offset = dst->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(dst->start);
unsigned long i = (start_offset + dst_offset) >> PAGE_SHIFT;
WARN_ON(src->len != dst_len);
- offset = (start_offset + dst_offset) &
- (PAGE_SIZE - 1);
+ offset = offset_in_page(start_offset + dst_offset);
while (len > 0) {
page = dst->pages[i];
@@ -5790,7 +5789,7 @@ static inline void eb_bitmap_offset(struct extent_buffer *eb,
unsigned long *page_index,
size_t *page_offset)
{
- size_t start_offset = eb->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(eb->start);
size_t byte_offset = BIT_BYTE(nr);
size_t offset;
@@ -5802,7 +5801,7 @@ static inline void eb_bitmap_offset(struct extent_buffer *eb,
offset = start_offset + start + byte_offset;
*page_index = offset >> PAGE_SHIFT;
- *page_offset = offset & (PAGE_SIZE - 1);
+ *page_offset = offset_in_page(offset);
}
/**
@@ -5944,7 +5943,7 @@ void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
size_t cur;
size_t dst_off_in_page;
size_t src_off_in_page;
- size_t start_offset = dst->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(dst->start);
unsigned long dst_i;
unsigned long src_i;
@@ -5962,10 +5961,8 @@ void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
}
while (len > 0) {
- dst_off_in_page = (start_offset + dst_offset) &
- (PAGE_SIZE - 1);
- src_off_in_page = (start_offset + src_offset) &
- (PAGE_SIZE - 1);
+ dst_off_in_page = offset_in_page(start_offset + dst_offset);
+ src_off_in_page = offset_in_page(start_offset + src_offset);
dst_i = (start_offset + dst_offset) >> PAGE_SHIFT;
src_i = (start_offset + src_offset) >> PAGE_SHIFT;
@@ -5993,7 +5990,7 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
size_t src_off_in_page;
unsigned long dst_end = dst_offset + len - 1;
unsigned long src_end = src_offset + len - 1;
- size_t start_offset = dst->start & ((u64)PAGE_SIZE - 1);
+ size_t start_offset = offset_in_page(dst->start);
unsigned long dst_i;
unsigned long src_i;
@@ -6017,10 +6014,8 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
dst_i = (start_offset + dst_end) >> PAGE_SHIFT;
src_i = (start_offset + src_end) >> PAGE_SHIFT;
- dst_off_in_page = (start_offset + dst_end) &
- (PAGE_SIZE - 1);
- src_off_in_page = (start_offset + src_end) &
- (PAGE_SIZE - 1);
+ dst_off_in_page = offset_in_page(start_offset + dst_end);
+ src_off_in_page = offset_in_page(start_offset + src_end);
cur = min_t(unsigned long, len, src_off_in_page + 1);
cur = min(cur, dst_off_in_page + 1);
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 711256baee22..cdf3fbd5dee4 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -414,7 +414,7 @@ static noinline int btrfs_copy_from_user(loff_t pos, size_t write_bytes,
size_t copied = 0;
size_t total_copied = 0;
int pg = 0;
- int offset = pos & (PAGE_SIZE - 1);
+ int offset = offset_in_page(pos);
while (write_bytes > 0) {
size_t count = min_t(size_t,
@@ -1625,7 +1625,7 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file,
return -ENOMEM;
while (iov_iter_count(i) > 0) {
- size_t offset = pos & (PAGE_SIZE - 1);
+ size_t offset = offset_in_page(pos);
struct extent_state *cached_state = NULL;
size_t sector_offset;
size_t write_bytes = min(iov_iter_count(i),
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d763d84b814e..c59c414b9efa 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -258,7 +258,7 @@ static int insert_inline_extent(struct btrfs_trans_handle *trans,
start >> PAGE_SHIFT);
btrfs_set_file_extent_compression(leaf, ei, 0);
kaddr = kmap_atomic(page);
- offset = start & (PAGE_SIZE - 1);
+ offset = offset_in_page(start);
write_extent_buffer(leaf, kaddr + offset, ptr, size);
kunmap_atomic(kaddr);
put_page(page);
@@ -584,8 +584,7 @@ static noinline void compress_file_range(struct inode *inode,
&total_compressed);
if (!ret) {
- unsigned long offset = total_compressed &
- (PAGE_SIZE - 1);
+ unsigned long offset = offset_in_page(total_compressed);
struct page *page = pages[nr_pages - 1];
char *kaddr;
@@ -9296,7 +9295,7 @@ int btrfs_page_mkwrite(struct vm_fault *vmf)
/* page is wholly or partially inside EOF */
if (page_start + PAGE_SIZE > size)
- zero_start = size & ~PAGE_MASK;
+ zero_start = offset_in_page(size);
else
zero_start = PAGE_SIZE;
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index b1bc501a5e0d..fc258a52feec 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -4812,7 +4812,7 @@ static ssize_t fill_read_buf(struct send_ctx *sctx, u64 offset, u32 len)
struct btrfs_key key;
pgoff_t index = offset >> PAGE_SHIFT;
pgoff_t last_index;
- unsigned pg_offset = offset & ~PAGE_MASK;
+ unsigned pg_offset = offset_in_page(offset);
ssize_t ret = 0;
key.objectid = sctx->cur_ino;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9dd348662e01..1e1129c7727f 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1102,7 +1102,7 @@ static int btrfs_read_disk_super(struct block_device *bdev, u64 bytenr,
p = kmap(*page);
/* align our pointer to the offset of the super block */
- *disk_super = p + (bytenr & ~PAGE_MASK);
+ *disk_super = p + offset_in_page(bytenr);
if (btrfs_super_bytenr(*disk_super) != bytenr ||
btrfs_super_magic(*disk_super) != BTRFS_MAGIC) {
--
2.27.0
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