From f0aad9baadb5b2933e6f4fbb2fd3ffbdcc35b2cf Mon Sep 17 00:00:00 2001 From: Jack Wang Date: Mon, 11 May 2020 15:51:27 +0200 Subject: [PATCH] block/rnbd: server: functionality for IO submitting to block dev This provides helper functions for IO submitting to block dev. Link: https://lore.kernel.org/r/20200511135131.27580-22-danil.kipnis@cloud.ionos.com Signed-off-by: Danil Kipnis Signed-off-by: Jack Wang Reviewed-by: Bart Van Assche Acked-by: Jens Axboe Signed-off-by: Jason Gunthorpe --- drivers/block/rnbd/rnbd-srv-dev.c | 134 ++++++++++++++++++++++++++++++++++++++ drivers/block/rnbd/rnbd-srv-dev.h | 92 ++++++++++++++++++++++++++ 2 files changed, 226 insertions(+) create mode 100644 drivers/block/rnbd/rnbd-srv-dev.c create mode 100644 drivers/block/rnbd/rnbd-srv-dev.h diff --git a/drivers/block/rnbd/rnbd-srv-dev.c b/drivers/block/rnbd/rnbd-srv-dev.c new file mode 100644 index 0000000..5eddfd2 --- /dev/null +++ b/drivers/block/rnbd/rnbd-srv-dev.c @@ -0,0 +1,134 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * RDMA Network Block Driver + * + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved. + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved. + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved. + */ +#undef pr_fmt +#define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt + +#include "rnbd-srv-dev.h" +#include "rnbd-log.h" + +struct rnbd_dev *rnbd_dev_open(const char *path, fmode_t flags, + struct bio_set *bs) +{ + struct rnbd_dev *dev; + int ret; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return ERR_PTR(-ENOMEM); + + dev->blk_open_flags = flags; + dev->bdev = blkdev_get_by_path(path, flags, THIS_MODULE); + ret = PTR_ERR_OR_ZERO(dev->bdev); + if (ret) + goto err; + + dev->blk_open_flags = flags; + bdevname(dev->bdev, dev->name); + dev->ibd_bio_set = bs; + + return dev; + +err: + kfree(dev); + return ERR_PTR(ret); +} + +void rnbd_dev_close(struct rnbd_dev *dev) +{ + blkdev_put(dev->bdev, dev->blk_open_flags); + kfree(dev); +} + +static void rnbd_dev_bi_end_io(struct bio *bio) +{ + struct rnbd_dev_blk_io *io = bio->bi_private; + + rnbd_endio(io->priv, blk_status_to_errno(bio->bi_status)); + bio_put(bio); +} + +/** + * rnbd_bio_map_kern - map kernel address into bio + * @data: pointer to buffer to map + * @bs: bio_set to use. + * @len: length in bytes + * @gfp_mask: allocation flags for bio allocation + * + * Map the kernel address into a bio suitable for io to a block + * device. Returns an error pointer in case of error. + */ +static struct bio *rnbd_bio_map_kern(void *data, struct bio_set *bs, + unsigned int len, gfp_t gfp_mask) +{ + unsigned long kaddr = (unsigned long)data; + unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT; + unsigned long start = kaddr >> PAGE_SHIFT; + const int nr_pages = end - start; + int offset, i; + struct bio *bio; + + bio = bio_alloc_bioset(gfp_mask, nr_pages, bs); + if (!bio) + return ERR_PTR(-ENOMEM); + + offset = offset_in_page(kaddr); + for (i = 0; i < nr_pages; i++) { + unsigned int bytes = PAGE_SIZE - offset; + + if (len <= 0) + break; + + if (bytes > len) + bytes = len; + + if (bio_add_page(bio, virt_to_page(data), bytes, + offset) < bytes) { + /* we don't support partial mappings */ + bio_put(bio); + return ERR_PTR(-EINVAL); + } + + data += bytes; + len -= bytes; + offset = 0; + } + + bio->bi_end_io = bio_put; + return bio; +} + +int rnbd_dev_submit_io(struct rnbd_dev *dev, sector_t sector, void *data, + size_t len, u32 bi_size, enum rnbd_io_flags flags, + short prio, void *priv) +{ + struct rnbd_dev_blk_io *io; + struct bio *bio; + + /* Generate bio with pages pointing to the rdma buffer */ + bio = rnbd_bio_map_kern(data, dev->ibd_bio_set, len, GFP_KERNEL); + if (IS_ERR(bio)) + return PTR_ERR(bio); + + io = container_of(bio, struct rnbd_dev_blk_io, bio); + + io->dev = dev; + io->priv = priv; + + bio->bi_end_io = rnbd_dev_bi_end_io; + bio->bi_private = io; + bio->bi_opf = rnbd_to_bio_flags(flags); + bio->bi_iter.bi_sector = sector; + bio->bi_iter.bi_size = bi_size; + bio_set_prio(bio, prio); + bio_set_dev(bio, dev->bdev); + + submit_bio(bio); + + return 0; +} diff --git a/drivers/block/rnbd/rnbd-srv-dev.h b/drivers/block/rnbd/rnbd-srv-dev.h new file mode 100644 index 0000000..0f65b09a --- /dev/null +++ b/drivers/block/rnbd/rnbd-srv-dev.h @@ -0,0 +1,92 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * RDMA Network Block Driver + * + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved. + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved. + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved. + */ +#ifndef RNBD_SRV_DEV_H +#define RNBD_SRV_DEV_H + +#include +#include "rnbd-proto.h" + +struct rnbd_dev { + struct block_device *bdev; + struct bio_set *ibd_bio_set; + fmode_t blk_open_flags; + char name[BDEVNAME_SIZE]; +}; + +struct rnbd_dev_blk_io { + struct rnbd_dev *dev; + void *priv; + /* have to be last member for front_pad usage of bioset_init */ + struct bio bio; +}; + +/** + * rnbd_dev_open() - Open a device + * @flags: open flags + * @bs: bio_set to use during block io, + */ +struct rnbd_dev *rnbd_dev_open(const char *path, fmode_t flags, + struct bio_set *bs); + +/** + * rnbd_dev_close() - Close a device + */ +void rnbd_dev_close(struct rnbd_dev *dev); + +void rnbd_endio(void *priv, int error); + +static inline int rnbd_dev_get_max_segs(const struct rnbd_dev *dev) +{ + return queue_max_segments(bdev_get_queue(dev->bdev)); +} + +static inline int rnbd_dev_get_max_hw_sects(const struct rnbd_dev *dev) +{ + return queue_max_hw_sectors(bdev_get_queue(dev->bdev)); +} + +static inline int rnbd_dev_get_secure_discard(const struct rnbd_dev *dev) +{ + return blk_queue_secure_erase(bdev_get_queue(dev->bdev)); +} + +static inline int rnbd_dev_get_max_discard_sects(const struct rnbd_dev *dev) +{ + if (!blk_queue_discard(bdev_get_queue(dev->bdev))) + return 0; + + return blk_queue_get_max_sectors(bdev_get_queue(dev->bdev), + REQ_OP_DISCARD); +} + +static inline int rnbd_dev_get_discard_granularity(const struct rnbd_dev *dev) +{ + return bdev_get_queue(dev->bdev)->limits.discard_granularity; +} + +static inline int rnbd_dev_get_discard_alignment(const struct rnbd_dev *dev) +{ + return bdev_get_queue(dev->bdev)->limits.discard_alignment; +} + +/** + * rnbd_dev_submit_io() - Submit an I/O to the disk + * @dev: device to that the I/O is submitted + * @sector: address to read/write data to + * @data: I/O data to write or buffer to read I/O date into + * @len: length of @data + * @bi_size: Amount of data that will be read/written + * @prio: IO priority + * @priv: private data passed to @io_fn + */ +int rnbd_dev_submit_io(struct rnbd_dev *dev, sector_t sector, void *data, + size_t len, u32 bi_size, enum rnbd_io_flags flags, + short prio, void *priv); + +#endif /* RNBD_SRV_DEV_H */ -- 2.7.4