| Message ID | 20211101203929.954622-4-willy@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iomap/xfs folio patches | expand |
On 11/1/21 2:39 PM, Matthew Wilcox (Oracle) wrote: > Allow callers to iterate over each folio instead of each page. The > bio need not have been constructed using folios originally. Reviewed-by: Jens Axboe <axboe@kernel.dk>
On Mon, Nov 01, 2021 at 08:39:11PM +0000, Matthew Wilcox (Oracle) wrote: > +static inline > +void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) Please fix the weird prototype formatting here. Otherwise looks good: Reviewed-by: Christoph Hellwig <hch@lst.de>
On Tue, Nov 02, 2021 at 12:13:22AM -0700, Christoph Hellwig wrote: > On Mon, Nov 01, 2021 at 08:39:11PM +0000, Matthew Wilcox (Oracle) wrote: > > +static inline > > +void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) > > Please fix the weird prototype formatting here. I dunno, it looks weirder this way: -static inline -void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) +static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, + int i) Anyway, I've made that change, but I still prefer it the way I had it. > Otherwise looks good: > > Reviewed-by: Christoph Hellwig <hch@lst.de>
On Tue, Nov 02, 2021 at 08:24:14PM +0000, Matthew Wilcox wrote: > On Tue, Nov 02, 2021 at 12:13:22AM -0700, Christoph Hellwig wrote: > > On Mon, Nov 01, 2021 at 08:39:11PM +0000, Matthew Wilcox (Oracle) wrote: > > > +static inline > > > +void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) > > > > Please fix the weird prototype formatting here. > > I dunno, it looks weirder this way: > > -static inline > -void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) > +static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, > + int i) > > Anyway, I've made that change, but I still prefer it the way I had it. I /think/ Christoph meant: static inline void bio_first_folio(...) Though the form that you've changed it to is also fine. --D > > Otherwise looks good: > > > > Reviewed-by: Christoph Hellwig <hch@lst.de>
On 11/2/21 4:24 PM, Darrick J. Wong wrote: > On Tue, Nov 02, 2021 at 08:24:14PM +0000, Matthew Wilcox wrote: >> On Tue, Nov 02, 2021 at 12:13:22AM -0700, Christoph Hellwig wrote: >>> On Mon, Nov 01, 2021 at 08:39:11PM +0000, Matthew Wilcox (Oracle) wrote: >>>> +static inline >>>> +void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) >>> >>> Please fix the weird prototype formatting here. >> >> I dunno, it looks weirder this way: >> >> -static inline >> -void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) >> +static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, >> + int i) >> >> Anyway, I've made that change, but I still prefer it the way I had it. > > I /think/ Christoph meant: > > static inline void > bio_first_folio(...) > > Though the form that you've changed it to is also fine. I won't speak for Christoph, but basically everything else in block follows the: static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) { } format, and this one should as well.
On Tue, Nov 02, 2021 at 04:33:39PM -0600, Jens Axboe wrote: > On 11/2/21 4:24 PM, Darrick J. Wong wrote: > > On Tue, Nov 02, 2021 at 08:24:14PM +0000, Matthew Wilcox wrote: > >> On Tue, Nov 02, 2021 at 12:13:22AM -0700, Christoph Hellwig wrote: > >>> On Mon, Nov 01, 2021 at 08:39:11PM +0000, Matthew Wilcox (Oracle) wrote: > >>>> +static inline > >>>> +void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) > >>> > >>> Please fix the weird prototype formatting here. > >> > >> I dunno, it looks weirder this way: > >> > >> -static inline > >> -void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) > >> +static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, > >> + int i) > >> > >> Anyway, I've made that change, but I still prefer it the way I had it. > > > > I /think/ Christoph meant: > > > > static inline void > > bio_first_folio(...) > > > > Though the form that you've changed it to is also fine. > > I won't speak for Christoph, but basically everything else in block > follows the: > > static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, > int i) > { > } > > format, and this one should as well. Durrr, /me forgot he was looking at block patches, not fs/iomap/. :( Sorry for the noise. --D > -- > Jens Axboe >
diff --git a/Documentation/core-api/kernel-api.rst b/Documentation/core-api/kernel-api.rst index 2e7186805148..7f0cb604b6ab 100644 --- a/Documentation/core-api/kernel-api.rst +++ b/Documentation/core-api/kernel-api.rst @@ -279,6 +279,7 @@ Accounting Framework Block Devices ============= +.. kernel-doc:: include/linux/bio.h .. kernel-doc:: block/blk-core.c :export: diff --git a/include/linux/bio.h b/include/linux/bio.h index a783cac49978..43b252a99334 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -166,7 +166,7 @@ static inline void bio_advance(struct bio *bio, unsigned int nbytes) */ #define bio_for_each_bvec_all(bvl, bio, i) \ for (i = 0, bvl = bio_first_bvec_all(bio); \ - i < (bio)->bi_vcnt; i++, bvl++) \ + i < (bio)->bi_vcnt; i++, bvl++) #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) @@ -260,6 +260,57 @@ static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) return &bio->bi_io_vec[bio->bi_vcnt - 1]; } +/** + * struct folio_iter - State for iterating all folios in a bio. + * @folio: The current folio we're iterating. NULL after the last folio. + * @offset: The byte offset within the current folio. + * @length: The number of bytes in this iteration (will not cross folio + * boundary). + */ +struct folio_iter { + struct folio *folio; + size_t offset; + size_t length; + /* private: for use by the iterator */ + size_t _seg_count; + int _i; +}; + +static inline +void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) +{ + struct bio_vec *bvec = bio_first_bvec_all(bio) + i; + + fi->folio = page_folio(bvec->bv_page); + fi->offset = bvec->bv_offset + + PAGE_SIZE * (bvec->bv_page - &fi->folio->page); + fi->_seg_count = bvec->bv_len; + fi->length = min(folio_size(fi->folio) - fi->offset, fi->_seg_count); + fi->_i = i; +} + +static inline void bio_next_folio(struct folio_iter *fi, struct bio *bio) +{ + fi->_seg_count -= fi->length; + if (fi->_seg_count) { + fi->folio = folio_next(fi->folio); + fi->offset = 0; + fi->length = min(folio_size(fi->folio), fi->_seg_count); + } else if (fi->_i + 1 < bio->bi_vcnt) { + bio_first_folio(fi, bio, fi->_i + 1); + } else { + fi->folio = NULL; + } +} + +/** + * bio_for_each_folio_all - Iterate over each folio in a bio. + * @fi: struct folio_iter which is updated for each folio. + * @bio: struct bio to iterate over. + */ +#define bio_for_each_folio_all(fi, bio) \ + for (bio_first_folio(&fi, bio, 0); fi.folio; bio_next_folio(&fi, bio)) + enum bip_flags { BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
Allow callers to iterate over each folio instead of each page. The bio need not have been constructed using folios originally. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- Documentation/core-api/kernel-api.rst | 1 + include/linux/bio.h | 53 ++++++++++++++++++++++++++- 2 files changed, 53 insertions(+), 1 deletion(-)