diff options
| -rw-r--r-- | fs/iomap.c | 170 | ||||
| -rw-r--r-- | fs/iomap/Makefile | 3 | ||||
| -rw-r--r-- | fs/iomap/swapfile.c | 180 |
3 files changed, 183 insertions, 170 deletions
diff --git a/fs/iomap.c b/fs/iomap.c index 217c3e5a13d6..521e90825dbe 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -2000,176 +2000,6 @@ out_free_dio: } EXPORT_SYMBOL_GPL(iomap_dio_rw); -/* Swapfile activation */ - -#ifdef CONFIG_SWAP -struct iomap_swapfile_info { - struct iomap iomap; /* accumulated iomap */ - struct swap_info_struct *sis; - uint64_t lowest_ppage; /* lowest physical addr seen (pages) */ - uint64_t highest_ppage; /* highest physical addr seen (pages) */ - unsigned long nr_pages; /* number of pages collected */ - int nr_extents; /* extent count */ -}; - -/* - * Collect physical extents for this swap file. Physical extents reported to - * the swap code must be trimmed to align to a page boundary. The logical - * offset within the file is irrelevant since the swapfile code maps logical - * page numbers of the swap device to the physical page-aligned extents. - */ -static int iomap_swapfile_add_extent(struct iomap_swapfile_info *isi) -{ - struct iomap *iomap = &isi->iomap; - unsigned long nr_pages; - uint64_t first_ppage; - uint64_t first_ppage_reported; - uint64_t next_ppage; - int error; - - /* - * Round the start up and the end down so that the physical - * extent aligns to a page boundary. - */ - first_ppage = ALIGN(iomap->addr, PAGE_SIZE) >> PAGE_SHIFT; - next_ppage = ALIGN_DOWN(iomap->addr + iomap->length, PAGE_SIZE) >> - PAGE_SHIFT; - - /* Skip too-short physical extents. */ - if (first_ppage >= next_ppage) - return 0; - nr_pages = next_ppage - first_ppage; - - /* - * Calculate how much swap space we're adding; the first page contains - * the swap header and doesn't count. The mm still wants that first - * page fed to add_swap_extent, however. - */ - first_ppage_reported = first_ppage; - if (iomap->offset == 0) - first_ppage_reported++; - if (isi->lowest_ppage > first_ppage_reported) - isi->lowest_ppage = first_ppage_reported; - if (isi->highest_ppage < (next_ppage - 1)) - isi->highest_ppage = next_ppage - 1; - - /* Add extent, set up for the next call. */ - error = add_swap_extent(isi->sis, isi->nr_pages, nr_pages, first_ppage); - if (error < 0) - return error; - isi->nr_extents += error; - isi->nr_pages += nr_pages; - return 0; -} - -/* - * Accumulate iomaps for this swap file. We have to accumulate iomaps because - * swap only cares about contiguous page-aligned physical extents and makes no - * distinction between written and unwritten extents. - */ -static loff_t iomap_swapfile_activate_actor(struct inode *inode, loff_t pos, - loff_t count, void *data, struct iomap *iomap) -{ - struct iomap_swapfile_info *isi = data; - int error; - - switch (iomap->type) { - case IOMAP_MAPPED: - case IOMAP_UNWRITTEN: - /* Only real or unwritten extents. */ - break; - case IOMAP_INLINE: - /* No inline data. */ - pr_err("swapon: file is inline\n"); - return -EINVAL; - default: - pr_err("swapon: file has unallocated extents\n"); - return -EINVAL; - } - - /* No uncommitted metadata or shared blocks. */ - if (iomap->flags & IOMAP_F_DIRTY) { - pr_err("swapon: file is not committed\n"); - return -EINVAL; - } - if (iomap->flags & IOMAP_F_SHARED) { - pr_err("swapon: file has shared extents\n"); - return -EINVAL; - } - - /* Only one bdev per swap file. */ - if (iomap->bdev != isi->sis->bdev) { - pr_err("swapon: file is on multiple devices\n"); - return -EINVAL; - } - - if (isi->iomap.length == 0) { - /* No accumulated extent, so just store it. */ - memcpy(&isi->iomap, iomap, sizeof(isi->iomap)); - } else if (isi->iomap.addr + isi->iomap.length == iomap->addr) { - /* Append this to the accumulated extent. */ - isi->iomap.length += iomap->length; - } else { - /* Otherwise, add the retained iomap and store this one. */ - error = iomap_swapfile_add_extent(isi); - if (error) - return error; - memcpy(&isi->iomap, iomap, sizeof(isi->iomap)); - } - return count; -} - -/* - * Iterate a swap file's iomaps to construct physical extents that can be - * passed to the swapfile subsystem. - */ -int iomap_swapfile_activate(struct swap_info_struct *sis, - struct file *swap_file, sector_t *pagespan, - const struct iomap_ops *ops) -{ - struct iomap_swapfile_info isi = { - .sis = sis, - .lowest_ppage = (sector_t)-1ULL, - }; - struct address_space *mapping = swap_file->f_mapping; - struct inode *inode = mapping->host; - loff_t pos = 0; - loff_t len = ALIGN_DOWN(i_size_read(inode), PAGE_SIZE); - loff_t ret; - - /* - * Persist all file mapping metadata so that we won't have any - * IOMAP_F_DIRTY iomaps. - */ - ret = vfs_fsync(swap_file, 1); - if (ret) - return ret; - - while (len > 0) { - ret = iomap_apply(inode, pos, len, IOMAP_REPORT, - ops, &isi, iomap_swapfile_activate_actor); - if (ret <= 0) - return ret; - - pos += ret; - len -= ret; - } - - if (isi.iomap.length) { - ret = iomap_swapfile_add_extent(&isi); - if (ret) - return ret; - } - - *pagespan = 1 + isi.highest_ppage - isi.lowest_ppage; - sis->max = isi.nr_pages; - sis->pages = isi.nr_pages - 1; - sis->highest_bit = isi.nr_pages - 1; - return isi.nr_extents; -} -EXPORT_SYMBOL_GPL(iomap_swapfile_activate); -#endif /* CONFIG_SWAP */ - static loff_t iomap_bmap_actor(struct inode *inode, loff_t pos, loff_t length, void *data, struct iomap *iomap) diff --git a/fs/iomap/Makefile b/fs/iomap/Makefile index de5a1f914b2c..f88eca22ae80 100644 --- a/fs/iomap/Makefile +++ b/fs/iomap/Makefile @@ -3,3 +3,6 @@ # Copyright (c) 2019 Oracle. # All Rights Reserved. # +obj-$(CONFIG_FS_IOMAP) += iomap.o + +iomap-$(CONFIG_SWAP) += swapfile.o diff --git a/fs/iomap/swapfile.c b/fs/iomap/swapfile.c new file mode 100644 index 000000000000..b79c33631263 --- /dev/null +++ b/fs/iomap/swapfile.c @@ -0,0 +1,180 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Oracle. All Rights Reserved. + * Author: Darrick J. Wong <darrick.wong@oracle.com> + */ +#include <linux/module.h> +#include <linux/compiler.h> +#include <linux/fs.h> +#include <linux/iomap.h> +#include <linux/swap.h> + +#include "../internal.h" + +/* Swapfile activation */ + +struct iomap_swapfile_info { + struct iomap iomap; /* accumulated iomap */ + struct swap_info_struct *sis; + uint64_t lowest_ppage; /* lowest physical addr seen (pages) */ + uint64_t highest_ppage; /* highest physical addr seen (pages) */ + unsigned long nr_pages; /* number of pages collected */ + int nr_extents; /* extent count */ +}; + +/* + * Collect physical extents for this swap file. Physical extents reported to + * the swap code must be trimmed to align to a page boundary. The logical + * offset within the file is irrelevant since the swapfile code maps logical + * page numbers of the swap device to the physical page-aligned extents. + */ +static int iomap_swapfile_add_extent(struct iomap_swapfile_info *isi) +{ + struct iomap *iomap = &isi->iomap; + unsigned long nr_pages; + uint64_t first_ppage; + uint64_t first_ppage_reported; + uint64_t next_ppage; + int error; + + /* + * Round the start up and the end down so that the physical + * extent aligns to a page boundary. + */ + first_ppage = ALIGN(iomap->addr, PAGE_SIZE) >> PAGE_SHIFT; + next_ppage = ALIGN_DOWN(iomap->addr + iomap->length, PAGE_SIZE) >> + PAGE_SHIFT; + + /* Skip too-short physical extents. */ + if (first_ppage >= next_ppage) + return 0; + nr_pages = next_ppage - first_ppage; + + /* + * Calculate how much swap space we're adding; the first page contains + * the swap header and doesn't count. The mm still wants that first + * page fed to add_swap_extent, however. + */ + first_ppage_reported = first_ppage; + if (iomap->offset == 0) + first_ppage_reported++; + if (isi->lowest_ppage > first_ppage_reported) + isi->lowest_ppage = first_ppage_reported; + if (isi->highest_ppage < (next_ppage - 1)) + isi->highest_ppage = next_ppage - 1; + + /* Add extent, set up for the next call. */ + error = add_swap_extent(isi->sis, isi->nr_pages, nr_pages, first_ppage); + if (error < 0) + return error; + isi->nr_extents += error; + isi->nr_pages += nr_pages; + return 0; +} + +/* + * Accumulate iomaps for this swap file. We have to accumulate iomaps because + * swap only cares about contiguous page-aligned physical extents and makes no + * distinction between written and unwritten extents. + */ +static loff_t iomap_swapfile_activate_actor(struct inode *inode, loff_t pos, + loff_t count, void *data, struct iomap *iomap) +{ + struct iomap_swapfile_info *isi = data; + int error; + + switch (iomap->type) { + case IOMAP_MAPPED: + case IOMAP_UNWRITTEN: + /* Only real or unwritten extents. */ + break; + case IOMAP_INLINE: + /* No inline data. */ + pr_err("swapon: file is inline\n"); + return -EINVAL; + default: + pr_err("swapon: file has unallocated extents\n"); + return -EINVAL; + } + + /* No uncommitted metadata or shared blocks. */ + if (iomap->flags & IOMAP_F_DIRTY) { + pr_err("swapon: file is not committed\n"); + return -EINVAL; + } + if (iomap->flags & IOMAP_F_SHARED) { + pr_err("swapon: file has shared extents\n"); + return -EINVAL; + } + + /* Only one bdev per swap file. */ + if (iomap->bdev != isi->sis->bdev) { + pr_err("swapon: file is on multiple devices\n"); + return -EINVAL; + } + + if (isi->iomap.length == 0) { + /* No accumulated extent, so just store it. */ + memcpy(&isi->iomap, iomap, sizeof(isi->iomap)); + } else if (isi->iomap.addr + isi->iomap.length == iomap->addr) { + /* Append this to the accumulated extent. */ + isi->iomap.length += iomap->length; + } else { + /* Otherwise, add the retained iomap and store this one. */ + error = iomap_swapfile_add_extent(isi); + if (error) + return error; + memcpy(&isi->iomap, iomap, sizeof(isi->iomap)); + } + return count; +} + +/* + * Iterate a swap file's iomaps to construct physical extents that can be + * passed to the swapfile subsystem. + */ +int iomap_swapfile_activate(struct swap_info_struct *sis, + struct file *swap_file, sector_t *pagespan, + const struct iomap_ops *ops) +{ + struct iomap_swapfile_info isi = { + .sis = sis, + .lowest_ppage = (sector_t)-1ULL, + }; + struct address_space *mapping = swap_file->f_mapping; + struct inode *inode = mapping->host; + loff_t pos = 0; + loff_t len = ALIGN_DOWN(i_size_read(inode), PAGE_SIZE); + loff_t ret; + + /* + * Persist all file mapping metadata so that we won't have any + * IOMAP_F_DIRTY iomaps. + */ + ret = vfs_fsync(swap_file, 1); + if (ret) + return ret; + + while (len > 0) { + ret = iomap_apply(inode, pos, len, IOMAP_REPORT, + ops, &isi, iomap_swapfile_activate_actor); + if (ret <= 0) + return ret; + + pos += ret; + len -= ret; + } + + if (isi.iomap.length) { + ret = iomap_swapfile_add_extent(&isi); + if (ret) + return ret; + } + + *pagespan = 1 + isi.highest_ppage - isi.lowest_ppage; + sis->max = isi.nr_pages; + sis->pages = isi.nr_pages - 1; + sis->highest_bit = isi.nr_pages - 1; + return isi.nr_extents; +} +EXPORT_SYMBOL_GPL(iomap_swapfile_activate); |