linux/fs/btrfs
Ira Weiny 3590ec5899 btrfs: use memcpy_[to|from]_page() and kmap_local_page()
There are many places where the pattern kmap/memcpy/kunmap occurs.

This pattern was lifted to the core common functions
memcpy_[to|from]_page().

Use these new functions to reduce the code, eliminate direct uses of
kmap, and leverage the new core functions use of kmap_local_page().

Also, there is 1 place where a kmap/memcpy is followed by an
optional memset.  Here we leave the kmap open coded to avoid remapping
the page but use kmap_local_page() directly.

Development of this patch was aided by the coccinelle script:

// <smpl>
// SPDX-License-Identifier: GPL-2.0-only
// Find kmap/memcpy/kunmap pattern and replace with memcpy*page calls
//
// NOTE: Offsets and other expressions may be more complex than what the script
// will automatically generate.  Therefore a catchall rule is provided to find
// the pattern which then must be evaluated by hand.
//
// Confidence: Low
// Copyright: (C) 2021 Intel Corporation
// URL: http://coccinelle.lip6.fr/
// Comments:
// Options:

//
// simple memcpy version
//
@ memcpy_rule1 @
expression page, T, F, B, Off;
identifier ptr;
type VP;
@@

(
-VP ptr = kmap(page);
|
-ptr = kmap(page);
|
-VP ptr = kmap_atomic(page);
|
-ptr = kmap_atomic(page);
)
<+...
(
-memcpy(ptr + Off, F, B);
+memcpy_to_page(page, Off, F, B);
|
-memcpy(ptr, F, B);
+memcpy_to_page(page, 0, F, B);
|
-memcpy(T, ptr + Off, B);
+memcpy_from_page(T, page, Off, B);
|
-memcpy(T, ptr, B);
+memcpy_from_page(T, page, 0, B);
)
...+>
(
-kunmap(page);
|
-kunmap_atomic(ptr);
)

// Remove any pointers left unused
@
depends on memcpy_rule1
@
identifier memcpy_rule1.ptr;
type VP, VP1;
@@

-VP ptr;
	... when != ptr;
? VP1 ptr;

//
// Some callers kmap without a temp pointer
//
@ memcpy_rule2 @
expression page, T, Off, F, B;
@@

<+...
(
-memcpy(kmap(page) + Off, F, B);
+memcpy_to_page(page, Off, F, B);
|
-memcpy(kmap(page), F, B);
+memcpy_to_page(page, 0, F, B);
|
-memcpy(T, kmap(page) + Off, B);
+memcpy_from_page(T, page, Off, B);
|
-memcpy(T, kmap(page), B);
+memcpy_from_page(T, page, 0, B);
)
...+>
-kunmap(page);
// No need for the ptr variable removal

//
// Catch all
//
@ memcpy_rule3 @
expression page;
expression GenTo, GenFrom, GenSize;
identifier ptr;
type VP;
@@

(
-VP ptr = kmap(page);
|
-ptr = kmap(page);
|
-VP ptr = kmap_atomic(page);
|
-ptr = kmap_atomic(page);
)
<+...
(
//
// Some call sites have complex expressions within the memcpy
// match a catch all to be evaluated by hand.
//
-memcpy(GenTo, GenFrom, GenSize);
+memcpy_to_pageExtra(page, GenTo, GenFrom, GenSize);
+memcpy_from_pageExtra(GenTo, page, GenFrom, GenSize);
)
...+>
(
-kunmap(page);
|
-kunmap_atomic(ptr);
)

// Remove any pointers left unused
@
depends on memcpy_rule3
@
identifier memcpy_rule3.ptr;
type VP, VP1;
@@

-VP ptr;
	... when != ptr;
? VP1 ptr;

// <smpl>

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-26 12:45:15 +01:00
..
tests btrfs: tests: initialize test inodes location 2020-12-18 14:59:49 +01:00
acl.c
async-thread.c Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
async-thread.h Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
backref.c btrfs: do not double free backref nodes on error 2021-01-18 15:44:53 +01:00
backref.h btrfs: rename BTRFS_ROOT_REF_COWS to BTRFS_ROOT_SHAREABLE 2020-05-25 11:25:35 +02:00
block-group.c btrfs: fix possible free space tree corruption with online conversion 2021-01-25 18:44:37 +01:00
block-group.h btrfs: load free space cache asynchronously 2020-12-08 15:54:03 +01:00
block-rsv.c btrfs: introduce mount option rescue=ignorebadroots 2020-12-08 15:53:41 +01:00
block-rsv.h btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
btrfs_inode.h btrfs: fix deadlock when cloning inline extent and low on free metadata space 2020-12-18 14:49:50 +01:00
check-integrity.c btrfs: drop casts of bio bi_sector 2020-12-09 19:16:05 +01:00
check-integrity.h btrfs: remove btrfsic_submit_bh() 2020-03-23 17:01:39 +01:00
compression.c btrfs: use memcpy_[to|from]_page() and kmap_local_page() 2021-02-26 12:45:15 +01:00
compression.h btrfs: compression: move declarations to header 2020-10-07 12:06:55 +02:00
ctree.c btrfs: correctly calculate item size used when item key collision happens 2020-12-18 14:50:00 +01:00
ctree.h for-5.11-rc5-tag 2021-01-29 13:54:40 -08:00
delalloc-space.c btrfs: add btrfs_reserve_data_bytes and use it 2020-10-07 12:06:52 +02:00
delalloc-space.h btrfs: make btrfs_delalloc_reserve_space take btrfs_inode 2020-07-27 12:55:36 +02:00
delayed-inode.c btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-inode.h btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-ref.c btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
delayed-ref.h
dev-replace.c btrfs: fix deadlock when cloning inline extent and low on free metadata space 2020-12-18 14:49:50 +01:00
dev-replace.h
dir-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
discard.c btrfs: merge critical sections of discard lock in workfn 2020-12-18 14:59:54 +01:00
discard.h btrfs: cleanup btrfs_discard_update_discardable usage 2020-12-08 15:54:02 +01:00
disk-io.c btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
disk-io.h btrfs: rename bio_offset of extent_submit_bio_start_t to dio_file_offset 2020-12-09 19:16:09 +01:00
export.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
export.h btrfs: export helpers for subvolume name/id resolution 2020-03-23 17:01:42 +01:00
extent_io.c btrfs: prevent NULL pointer dereference in extent_io_tree_panic 2021-01-07 17:25:05 +01:00
extent_io.h btrfs: update num_extent_pages to support subpage sized extent buffer 2020-12-09 19:16:10 +01:00
extent_map.c Btrfs: fix race between using extent maps and merging them 2020-02-12 17:16:46 +01:00
extent_map.h btrfs: remove extent_map::bdev 2019-11-18 23:43:44 +01:00
extent-io-tree.h btrfs: use fixed width int type for extent_state::state 2020-12-08 15:54:13 +01:00
extent-tree.c btrfs: fix log replay failure due to race with space cache rebuild 2021-01-25 18:44:53 +01:00
file-item.c btrfs: correctly calculate item size used when item key collision happens 2020-12-18 14:50:00 +01:00
file.c btrfs: disable fallocate in ZONED mode 2020-12-09 19:16:04 +01:00
free-space-cache.c btrfs: remove free space items when disabling space cache v1 2020-12-09 19:16:09 +01:00
free-space-cache.h btrfs: remove free space items when disabling space cache v1 2020-12-09 19:16:09 +01:00
free-space-tree.c btrfs: fix possible free space tree corruption with online conversion 2021-01-25 18:44:37 +01:00
free-space-tree.h btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
inode-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
inode.c btrfs: shrink delalloc pages instead of full inodes 2021-01-08 16:36:44 +01:00
ioctl.c btrfs: fix deadlock when cloning inline extent and low on free metadata space 2020-12-18 14:49:50 +01:00
Kconfig btrfs: switch to iomap for direct IO 2020-10-07 12:06:57 +02:00
locking.c btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
locking.h btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
lzo.c btrfs: use memcpy_[to|from]_page() and kmap_local_page() 2021-02-26 12:45:15 +01:00
Makefile btrfs: remove inode number cache feature 2020-12-09 19:16:05 +01:00
misc.h btrfs: rename tree_entry to rb_simple_node and export it 2020-05-25 11:25:19 +02:00
ordered-data.c btrfs: remove btrfs_find_ordered_sum call from btrfs_lookup_bio_sums 2020-12-09 19:16:10 +01:00
ordered-data.h btrfs: remove btrfs_find_ordered_sum call from btrfs_lookup_bio_sums 2020-12-09 19:16:10 +01:00
orphan.c
print-tree.c btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
print-tree.h btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
props.c btrfs: simplify iget helpers 2020-05-25 11:25:37 +02:00
props.h
qgroup.c btrfs: fix transaction leak and crash after RO remount caused by qgroup rescan 2020-12-18 14:59:57 +01:00
qgroup.h btrfs: qgroup: export qgroups in sysfs 2020-07-27 12:55:37 +02:00
raid56.c btrfs: drop casts of bio bi_sector 2020-12-09 19:16:05 +01:00
raid56.h
rcu-string.h btrfs: rcu-string: Replace zero-length array with flexible-array member 2020-03-23 17:01:53 +01:00
reada.c btrfs: pass the owner_root and level to alloc_extent_buffer 2020-12-08 15:54:07 +01:00
ref-verify.c btrfs: use btrfs_read_node_slot in walk_down_tree 2020-12-08 15:54:06 +01:00
ref-verify.h
reflink.c btrfs: use memcpy_[to|from]_page() and kmap_local_page() 2021-02-26 12:45:15 +01:00
reflink.h Btrfs: move all reflink implementation code into its own file 2020-03-23 17:01:54 +01:00
relocation.c btrfs: reloc: fix wrong file extent type check to avoid false ENOENT 2021-01-07 17:25:05 +01:00
root-tree.c btrfs: qgroup: fix qgroup meta rsv leak for subvolume operations 2020-10-07 12:12:13 +02:00
scrub.c btrfs: scrub: allow scrub to work with subpage sectorsize 2020-12-09 19:16:11 +01:00
send.c btrfs: use memcpy_[to|from]_page() and kmap_local_page() 2021-02-26 12:45:15 +01:00
send.h btrfs: send: avoid copying file data 2020-10-07 12:13:17 +02:00
space-info.c btrfs: shrink delalloc pages instead of full inodes 2021-01-08 16:36:44 +01:00
space-info.h btrfs: add btrfs_reserve_data_bytes and use it 2020-10-07 12:06:52 +02:00
struct-funcs.c btrfs: handle sectorsize < PAGE_SIZE case for extent buffer accessors 2020-12-09 19:16:10 +01:00
super.c btrfs: run delayed iputs when remounting RO to avoid leaking them 2020-12-18 15:00:08 +01:00
sysfs.c for-5.11/block-2020-12-14 2020-12-16 12:57:51 -08:00
sysfs.h btrfs: split and refactor btrfs_sysfs_remove_devices_dir 2020-10-07 12:12:21 +02:00
transaction.c btrfs: no need to run delayed refs after commit_fs_roots during commit 2021-01-12 15:35:04 +01:00
transaction.h btrfs: return bool from btrfs_should_end_transaction 2020-12-08 15:54:16 +01:00
tree-checker.c btrfs: tree-checker: check if chunk item end overflows 2021-01-07 17:25:05 +01:00
tree-checker.h
tree-defrag.c btrfs: locking: remove all the blocking helpers 2020-12-08 15:54:01 +01:00
tree-log.c btrfs: do not block inode logging for so long during transaction commit 2020-12-09 19:16:07 +01:00
tree-log.h btrfs: make fast fsyncs wait only for writeback 2020-10-07 12:06:56 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: remove unnecessary casts in printk 2020-12-08 15:53:52 +01:00
volumes.c for-5.11-rc5-tag 2021-01-29 13:54:40 -08:00
volumes.h btrfs: fix lockdep warning due to seqcount_mutex on 32bit arch 2021-01-25 18:44:50 +01:00
xattr.c btrfs: skip unnecessary searches for xattrs when logging an inode 2020-12-08 15:54:12 +01:00
xattr.h
zlib.c btrfs: use memcpy_[to|from]_page() and kmap_local_page() 2021-02-26 12:45:15 +01:00
zoned.c for-5.11/block-2020-12-14 2020-12-16 12:57:51 -08:00
zoned.h btrfs: implement log-structured superblock for ZONED mode 2020-12-09 19:16:04 +01:00
zstd.c btrfs: use memcpy_[to|from]_page() and kmap_local_page() 2021-02-26 12:45:15 +01:00