diff options
Diffstat (limited to 'drivers/dax/super.c')
| -rw-r--r-- | drivers/dax/super.c | 98 |
1 files changed, 58 insertions, 40 deletions
diff --git a/drivers/dax/super.c b/drivers/dax/super.c index bbd57ca0634a..4e5ae7e8b557 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -1,14 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Copyright(c) 2017 Intel Corporation. All rights reserved. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of version 2 of the GNU General Public License as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. */ #include <linux/pagemap.h> #include <linux/module.h> @@ -73,22 +65,12 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); #endif -/** - * __bdev_dax_supported() - Check if the device supports dax for filesystem - * @bdev: block device to check - * @blocksize: The block size of the device - * - * This is a library function for filesystems to check if the block device - * can be mounted with dax option. - * - * Return: true if supported, false if unsupported - */ -bool __bdev_dax_supported(struct block_device *bdev, int blocksize) +bool __generic_fsdax_supported(struct dax_device *dax_dev, + struct block_device *bdev, int blocksize, sector_t start, + sector_t sectors) { - struct dax_device *dax_dev; bool dax_enabled = false; pgoff_t pgoff, pgoff_end; - struct request_queue *q; char buf[BDEVNAME_SIZE]; void *kaddr, *end_kaddr; pfn_t pfn, end_pfn; @@ -102,21 +84,14 @@ bool __bdev_dax_supported(struct block_device *bdev, int blocksize) return false; } - q = bdev_get_queue(bdev); - if (!q || !blk_queue_dax(q)) { - pr_debug("%s: error: request queue doesn't support dax\n", - bdevname(bdev, buf)); - return false; - } - - err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff); + err = bdev_dax_pgoff(bdev, start, PAGE_SIZE, &pgoff); if (err) { pr_debug("%s: error: unaligned partition for dax\n", bdevname(bdev, buf)); return false; } - last_page = PFN_DOWN(i_size_read(bdev->bd_inode) - 1) * 8; + last_page = PFN_DOWN((start + sectors - 1) * 512) * PAGE_SIZE / 512; err = bdev_dax_pgoff(bdev, last_page, PAGE_SIZE, &pgoff_end); if (err) { pr_debug("%s: error: unaligned partition for dax\n", @@ -124,20 +99,11 @@ bool __bdev_dax_supported(struct block_device *bdev, int blocksize) return false; } - dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); - if (!dax_dev) { - pr_debug("%s: error: device does not support dax\n", - bdevname(bdev, buf)); - return false; - } - id = dax_read_lock(); len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn); len2 = dax_direct_access(dax_dev, pgoff_end, 1, &end_kaddr, &end_pfn); dax_read_unlock(id); - put_dax(dax_dev); - if (len < 1 || len2 < 1) { pr_debug("%s: error: dax access failed (%ld)\n", bdevname(bdev, buf), len < 1 ? len : len2); @@ -178,6 +144,49 @@ bool __bdev_dax_supported(struct block_device *bdev, int blocksize) } return true; } +EXPORT_SYMBOL_GPL(__generic_fsdax_supported); + +/** + * __bdev_dax_supported() - Check if the device supports dax for filesystem + * @bdev: block device to check + * @blocksize: The block size of the device + * + * This is a library function for filesystems to check if the block device + * can be mounted with dax option. + * + * Return: true if supported, false if unsupported + */ +bool __bdev_dax_supported(struct block_device *bdev, int blocksize) +{ + struct dax_device *dax_dev; + struct request_queue *q; + char buf[BDEVNAME_SIZE]; + bool ret; + int id; + + q = bdev_get_queue(bdev); + if (!q || !blk_queue_dax(q)) { + pr_debug("%s: error: request queue doesn't support dax\n", + bdevname(bdev, buf)); + return false; + } + + dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); + if (!dax_dev) { + pr_debug("%s: error: device does not support dax\n", + bdevname(bdev, buf)); + return false; + } + + id = dax_read_lock(); + ret = dax_supported(dax_dev, bdev, blocksize, 0, + i_size_read(bdev->bd_inode) / 512); + dax_read_unlock(id); + + put_dax(dax_dev); + + return ret; +} EXPORT_SYMBOL_GPL(__bdev_dax_supported); #endif @@ -303,6 +312,15 @@ long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages, } EXPORT_SYMBOL_GPL(dax_direct_access); +bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev, + int blocksize, sector_t start, sector_t len) +{ + if (!dax_alive(dax_dev)) + return false; + + return dax_dev->ops->dax_supported(dax_dev, bdev, blocksize, start, len); +} + size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i) { |