diff options
Diffstat (limited to 'fs/iomap/swapfile.c')
| -rw-r--r-- | fs/iomap/swapfile.c | 92 |
1 files changed, 54 insertions, 38 deletions
diff --git a/fs/iomap/swapfile.c b/fs/iomap/swapfile.c index a648dbf6991e..5fc0ac36dee3 100644 --- a/fs/iomap/swapfile.c +++ b/fs/iomap/swapfile.c @@ -18,6 +18,7 @@ struct iomap_swapfile_info { uint64_t highest_ppage; /* highest physical addr seen (pages) */ unsigned long nr_pages; /* number of pages collected */ int nr_extents; /* extent count */ + struct file *file; }; /* @@ -30,11 +31,16 @@ static int iomap_swapfile_add_extent(struct iomap_swapfile_info *isi) { struct iomap *iomap = &isi->iomap; unsigned long nr_pages; + unsigned long max_pages; uint64_t first_ppage; uint64_t first_ppage_reported; uint64_t next_ppage; int error; + if (unlikely(isi->nr_pages >= isi->sis->max)) + return 0; + max_pages = isi->sis->max - isi->nr_pages; + /* * Round the start up and the end down so that the physical * extent aligns to a page boundary. @@ -47,6 +53,7 @@ static int iomap_swapfile_add_extent(struct iomap_swapfile_info *isi) if (first_ppage >= next_ppage) return 0; nr_pages = next_ppage - first_ppage; + nr_pages = min(nr_pages, max_pages); /* * Calculate how much swap space we're adding; the first page contains @@ -70,18 +77,26 @@ static int iomap_swapfile_add_extent(struct iomap_swapfile_info *isi) return 0; } +static int iomap_swapfile_fail(struct iomap_swapfile_info *isi, const char *str) +{ + char *buf, *p = ERR_PTR(-ENOMEM); + + buf = kmalloc(PATH_MAX, GFP_KERNEL); + if (buf) + p = file_path(isi->file, buf, PATH_MAX); + pr_err("swapon: file %s %s\n", IS_ERR(p) ? "<unknown>" : p, str); + kfree(buf); + return -EINVAL; +} + /* * 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 *srcmap) +static loff_t iomap_swapfile_iter(const struct iomap_iter *iter, + struct iomap *iomap, struct iomap_swapfile_info *isi) { - struct iomap_swapfile_info *isi = data; - int error; - switch (iomap->type) { case IOMAP_MAPPED: case IOMAP_UNWRITTEN: @@ -89,28 +104,20 @@ static loff_t iomap_swapfile_activate_actor(struct inode *inode, loff_t pos, break; case IOMAP_INLINE: /* No inline data. */ - pr_err("swapon: file is inline\n"); - return -EINVAL; + return iomap_swapfile_fail(isi, "is inline"); default: - pr_err("swapon: file has unallocated extents\n"); - return -EINVAL; + return iomap_swapfile_fail(isi, "has unallocated extents"); } /* 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; - } + if (iomap->flags & IOMAP_F_DIRTY) + return iomap_swapfile_fail(isi, "is not committed"); + if (iomap->flags & IOMAP_F_SHARED) + return iomap_swapfile_fail(isi, "has shared extents"); /* Only one bdev per swap file. */ - if (iomap->bdev != isi->sis->bdev) { - pr_err("swapon: file is on multiple devices\n"); - return -EINVAL; - } + if (iomap->bdev != isi->sis->bdev) + return iomap_swapfile_fail(isi, "outside the main device"); if (isi->iomap.length == 0) { /* No accumulated extent, so just store it. */ @@ -120,12 +127,12 @@ static loff_t iomap_swapfile_activate_actor(struct inode *inode, loff_t pos, isi->iomap.length += iomap->length; } else { /* Otherwise, add the retained iomap and store this one. */ - error = iomap_swapfile_add_extent(isi); + int error = iomap_swapfile_add_extent(isi); if (error) return error; memcpy(&isi->iomap, iomap, sizeof(isi->iomap)); } - return count; + return iomap_length(iter); } /* @@ -136,15 +143,19 @@ int iomap_swapfile_activate(struct swap_info_struct *sis, struct file *swap_file, sector_t *pagespan, const struct iomap_ops *ops) { + struct inode *inode = swap_file->f_mapping->host; + struct iomap_iter iter = { + .inode = inode, + .pos = 0, + .len = ALIGN_DOWN(i_size_read(inode), PAGE_SIZE), + .flags = IOMAP_REPORT, + }; struct iomap_swapfile_info isi = { .sis = sis, .lowest_ppage = (sector_t)-1ULL, + .file = swap_file, }; - 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; + int ret; /* * Persist all file mapping metadata so that we won't have any @@ -154,15 +165,10 @@ int iomap_swapfile_activate(struct swap_info_struct *sis, 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; - } + while ((ret = iomap_iter(&iter, ops)) > 0) + iter.processed = iomap_swapfile_iter(&iter, &iter.iomap, &isi); + if (ret < 0) + return ret; if (isi.iomap.length) { ret = iomap_swapfile_add_extent(&isi); @@ -170,6 +176,16 @@ int iomap_swapfile_activate(struct swap_info_struct *sis, return ret; } + /* + * If this swapfile doesn't contain even a single page-aligned + * contiguous range of blocks, reject this useless swapfile to + * prevent confusion later on. + */ + if (isi.nr_pages == 0) { + pr_warn("swapon: Cannot find a single usable page in file.\n"); + return -EINVAL; + } + *pagespan = 1 + isi.highest_ppage - isi.lowest_ppage; sis->max = isi.nr_pages; sis->pages = isi.nr_pages - 1; |