kernel.git/fs/btrfs/misc.h, branch linux-rolling-lts

btrfs: define the AUTO_KFREE/AUTO_KVFREE helper macros

2026-03-12T11:09:31Z

[ Upstream commit d00cbce0a7d5de5fc31bf60abd59b44d36806b6e ] These are two simple macros which ensure that a pointer is initialized to NULL and with the proper cleanup attribute for it. Signed-off-by: Miquel Sabaté Solà Reviewed-by: David Sterba Signed-off-by: David Sterba Stable-dep-of: 52ee9965d09b ("btrfs: zoned: fixup last alloc pointer after extent removal for RAID0/10") Signed-off-by: Sasha Levin

btrfs: introduce btrfs_bio_for_each_block_all() helper

2025-09-23T06:49:17Z

Currently if we want to iterate all blocks inside a bio, we do something like this: bio_for_each_segment_all(bvec, bio, iter_all) { for (off = 0; off < bvec->bv_len; off += sectorsize) { /* Iterate blocks using bv + off */ } } That's fine for now, but it will not handle future bs > ps, as bio_for_each_segment_all() is a single-page iterator, it will always return a bvec that's no larger than a page. But for bs > ps cases, we need a full folio (which covers at least one block) so that we can work on the block. To address this problem and handle future bs > ps cases better: - Introduce a helper btrfs_bio_for_each_block_all() This helper will create a local bvec_iter, which has the size of the target bio. Then grab the current physical address of the current location, then advance the iterator by block size. - Use btrfs_bio_for_each_block_all() to replace existing call sites Including: * set_bio_pages_uptodate() in raid56 * verify_bio_data_sectors() in raid56 Both will result much easier to read code. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba

btrfs: introduce btrfs_bio_for_each_block() helper

2025-09-23T06:49:17Z

Currently if we want to iterate a bio in block unit, we do something like this: while (iter->bi_size) { struct bio_vec bv = bio_iter_iovec(); /* Do something with using the bv */ bio_advance_iter_single(&bbio->bio, iter, sectorsize); } That's fine for now, but it will not handle future bs > ps, as bio_iter_iovec() returns a single-page bvec, meaning the bv_len will not exceed page size. This means the code using that bv can only handle a block if bs <= ps. To address this problem and handle future bs > ps cases better: - Introduce a helper btrfs_bio_for_each_block() Instead of bio_vec, which has single and multiple page version and multiple page version has quite some limits, use my favorite way to represent a block, phys_addr_t. For bs <= ps cases, nothing is changed, except we will do a very small overhead to convert phys_addr_t to a folio, then use the proper folio helpers to handle the possible highmem cases. For bs > ps cases, all blocks will be backed by large folios, meaning every folio will cover at least one block. And still use proper folio helpers to handle highmem cases. With phys_addr_t, we will handle both large folio and highmem properly. So there is no better single variable to present a btrfs block than phys_addr_t. - Extract the data block csum calculation into a helper The new helper, btrfs_calculate_block_csum() will be utilized by btrfs_csum_one_bio(). - Use btrfs_bio_for_each_block() to replace existing call sites Including: * index_one_bio() from raid56.c Very straight-forward. * btrfs_check_read_bio() Also update repair_one_sector() to grab the folio using phys_addr_t, and do extra checks to make sure the folio covers at least one block. We do not need to bother bv_len at all now. * btrfs_csum_one_bio() Now we can move the highmem handling into a dedicated helper, calculate_block_csum(), and use btrfs_bio_for_each_block() helper. There is one exception in btrfs_decompress_buf2page(), which is copying decompressed data into the original bio, which is not iterating using block size thus we don't need to bother. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba

btrfs: add helper folio_end()

2025-07-21T21:58:01Z

There are several cases of folio_pos + folio_size, add a convenience helper for that. This is a local helper and not proposed as folio API because it does not seem to be heavily used elsewhere: A quick grep (folio_size + folio_end) in fs/ shows 24 btrfs 4 iomap 4 ext4 2 xfs 2 netfs 1 gfs2 1 f2fs 1 bcachefs 1 buffer.c Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba

btrfs: use rb_find_add() in rb_simple_insert()

2025-07-21T21:53:26Z

Use the rb-tree helper so we don't open code the search and insert code. Signed-off-by: Pan Chuang Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: pass struct rb_simple_node pointer directly in rb_simple_insert()

2025-07-21T21:53:26Z

Replace struct embedding with union to enable safe type conversion in btrfs_backref_node, tree_block and mapping_node. Adjust function calls to use the new unified API, eliminating redundant parameters. Signed-off-by: Pan Chuang Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: constify pointer parameters where applicable

2024-07-11T13:33:22Z

We can add const to many parameters, this is for clarity and minor addition to safety. There are some minor effects, in the assembly code and .ko measured on release config. This patch does not cover all possible conversions. Signed-off-by: David Sterba

btrfs: add forward declarations and headers, part 2

2024-03-04T15:24:49Z

Do a cleanup in more headers: - add forward declarations for types referenced by pointers - add includes when types need them This fixes potential compilation problems if the headers are reordered or the missing includes are not provided indirectly. Signed-off-by: David Sterba

minmax: add in_range() macro

2023-08-24T23:20:18Z

Patch series "New page table range API", v6. This patchset changes the API used by the MM to set up page table entries. The four APIs are: set_ptes(mm, addr, ptep, pte, nr) update_mmu_cache_range(vma, addr, ptep, nr) flush_dcache_folio(folio) flush_icache_pages(vma, page, nr) flush_dcache_folio() isn't technically new, but no architecture implemented it, so I've done that for them. The old APIs remain around but are mostly implemented by calling the new interfaces. The new APIs are based around setting up N page table entries at once. The N entries belong to the same PMD, the same folio and the same VMA, so ptep++ is a legitimate operation, and locking is taken care of for you. Some architectures can do a better job of it than just a loop, but I have hesitated to make too deep a change to architectures I don't understand well. One thing I have changed in every architecture is that PG_arch_1 is now a per-folio bit instead of a per-page bit when used for dcache clean/dirty tracking. This was something that would have to happen eventually, and it makes sense to do it now rather than iterate over every page involved in a cache flush and figure out if it needs to happen. The point of all this is better performance, and Fengwei Yin has measured improvement on x86. I suspect you'll see improvement on your architecture too. Try the new will-it-scale test mentioned here: https://lore.kernel.org/linux-mm/20230206140639.538867-5-fengwei.yin@intel.com/ You'll need to run it on an XFS filesystem and have CONFIG_TRANSPARENT_HUGEPAGE set. This patchset is the basis for much of the anonymous large folio work being done by Ryan, so it's received quite a lot of testing over the last few months. This patch (of 38): Determine if a value lies within a range more efficiently (subtraction + comparison vs two comparisons and an AND). It also has useful (under some circumstances) behaviour if the range exceeds the maximum value of the type. Convert all the conflicting definitions of in_range() within the kernel; some can use the generic definition while others need their own definition. Link: https://lkml.kernel.org/r/20230802151406.3735276-1-willy@infradead.org Link: https://lkml.kernel.org/r/20230802151406.3735276-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton

btrfs: export bitmap_test_range_all_{set,zero}

2023-06-19T11:59:22Z

bitmap_test_range_all_{set,zero} defined in subpage.c are useful for other components. Move them to misc.h and use them in zoned.c. Also, as find_next{,_zero}_bit take/return "unsigned long" instead of "unsigned int", convert the type to "unsigned long". While at it, also rewrite the "if (...) return true; else return false;" pattern and add const to the input bitmap. Signed-off-by: Naohiro Aota Reviewed-by: David Sterba Signed-off-by: David Sterba