From 09230435dffdb13de507e5e40b524b0069fc5c7b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 3 Jul 2018 09:07:46 -0700 Subject: [PATCH] iomap: refactor iomap_dio_actor Split the function up into two helpers for the bio based I/O and hole case, and a small helper to call the two. This separates the code a little better in preparation for supporting I/O to inline data. Signed-off-by: Christoph Hellwig Reviewed-by: Andreas Gruenbacher Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/iomap.c | 88 ++++++++++++++++++++++++++++++++---------------------- 1 file changed, 52 insertions(+), 36 deletions(-) diff --git a/fs/iomap.c b/fs/iomap.c index 2ebff76039b5..4d8ff0f5ecc9 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -1327,10 +1327,9 @@ iomap_dio_zero(struct iomap_dio *dio, struct iomap *iomap, loff_t pos, } static loff_t -iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, - void *data, struct iomap *iomap) +iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, + struct iomap_dio *dio, struct iomap *iomap) { - struct iomap_dio *dio = data; unsigned int blkbits = blksize_bits(bdev_logical_block_size(iomap->bdev)); unsigned int fs_block_size = i_blocksize(inode), pad; unsigned int align = iov_iter_alignment(dio->submit.iter); @@ -1344,41 +1343,27 @@ iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, if ((pos | length | align) & ((1 << blkbits) - 1)) return -EINVAL; - switch (iomap->type) { - case IOMAP_HOLE: - if (WARN_ON_ONCE(dio->flags & IOMAP_DIO_WRITE)) - return -EIO; - /*FALLTHRU*/ - case IOMAP_UNWRITTEN: - if (!(dio->flags & IOMAP_DIO_WRITE)) { - length = iov_iter_zero(length, dio->submit.iter); - dio->size += length; - return length; - } + if (iomap->type == IOMAP_UNWRITTEN) { dio->flags |= IOMAP_DIO_UNWRITTEN; need_zeroout = true; - break; - case IOMAP_MAPPED: - if (iomap->flags & IOMAP_F_SHARED) - dio->flags |= IOMAP_DIO_COW; - if (iomap->flags & IOMAP_F_NEW) { - need_zeroout = true; - } else { - /* - * Use a FUA write if we need datasync semantics, this - * is a pure data IO that doesn't require any metadata - * updates and the underlying device supports FUA. This - * allows us to avoid cache flushes on IO completion. - */ - if (!(iomap->flags & (IOMAP_F_SHARED|IOMAP_F_DIRTY)) && - (dio->flags & IOMAP_DIO_WRITE_FUA) && - blk_queue_fua(bdev_get_queue(iomap->bdev))) - use_fua = true; - } - break; - default: - WARN_ON_ONCE(1); - return -EIO; + } + + if (iomap->flags & IOMAP_F_SHARED) + dio->flags |= IOMAP_DIO_COW; + + if (iomap->flags & IOMAP_F_NEW) { + need_zeroout = true; + } else { + /* + * Use a FUA write if we need datasync semantics, this + * is a pure data IO that doesn't require any metadata + * updates and the underlying device supports FUA. This + * allows us to avoid cache flushes on IO completion. + */ + if (!(iomap->flags & (IOMAP_F_SHARED|IOMAP_F_DIRTY)) && + (dio->flags & IOMAP_DIO_WRITE_FUA) && + blk_queue_fua(bdev_get_queue(iomap->bdev))) + use_fua = true; } /* @@ -1457,6 +1442,37 @@ iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, return copied; } +static loff_t +iomap_dio_hole_actor(loff_t length, struct iomap_dio *dio) +{ + length = iov_iter_zero(length, dio->submit.iter); + dio->size += length; + return length; +} + +static loff_t +iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length, + void *data, struct iomap *iomap) +{ + struct iomap_dio *dio = data; + + switch (iomap->type) { + case IOMAP_HOLE: + if (WARN_ON_ONCE(dio->flags & IOMAP_DIO_WRITE)) + return -EIO; + return iomap_dio_hole_actor(length, dio); + case IOMAP_UNWRITTEN: + if (!(dio->flags & IOMAP_DIO_WRITE)) + return iomap_dio_hole_actor(length, dio); + return iomap_dio_bio_actor(inode, pos, length, dio, iomap); + case IOMAP_MAPPED: + return iomap_dio_bio_actor(inode, pos, length, dio, iomap); + default: + WARN_ON_ONCE(1); + return -EIO; + } +} + /* * iomap_dio_rw() always completes O_[D]SYNC writes regardless of whether the IO * is being issued as AIO or not. This allows us to optimise pure data writes -- 2.30.2