On Tue, May 12, 2026 at 07:35:18AM +0200, Christoph Hellwig wrote: > Make the core swap code calculate sis->pages, nr_extents and the span, > re-set sis->max based on it and don't require passing the current offset > into the swap file to swap_add_extent as all that can trivially be > calculated internally. Also truncate the spans based on the available > information. > > All this removes a lot of boilerplate code in the callers. > > Signed-off-by: Christoph Hellwig <[email protected]>
Looks great to me. I'm glad the weird @span parameter goes away with this. Reviewed-by: "Darrick J. Wong" <[email protected]> --D > --- > Documentation/filesystems/locking.rst | 2 +- > Documentation/filesystems/vfs.rst | 2 +- > fs/btrfs/inode.c | 58 ++----------- > fs/ext4/inode.c | 5 +- > fs/f2fs/data.c | 38 ++------- > fs/iomap/swapfile.c | 58 +------------ > fs/nfs/file.c | 9 +- > fs/ntfs/aops.c | 5 +- > fs/smb/client/file.c | 5 +- > fs/xfs/xfs_aops.c | 6 +- > fs/zonefs/file.c | 5 +- > include/linux/fs.h | 3 +- > include/linux/iomap.h | 5 +- > include/linux/swap.h | 11 ++- > mm/page_io.c | 39 ++------- > mm/swapfile.c | 116 ++++++++++++++++---------- > 16 files changed, 121 insertions(+), 246 deletions(-) > > diff --git a/Documentation/filesystems/locking.rst > b/Documentation/filesystems/locking.rst > index 8421ea21bd35..f3658204d070 100644 > --- a/Documentation/filesystems/locking.rst > +++ b/Documentation/filesystems/locking.rst > @@ -264,7 +264,7 @@ prototypes:: > int (*launder_folio)(struct folio *); > bool (*is_partially_uptodate)(struct folio *, size_t from, size_t > count); > int (*error_remove_folio)(struct address_space *, struct folio *); > - int (*swap_activate)(struct swap_info_struct *sis, struct file *f, > sector_t *span) > + int (*swap_activate)(struct swap_info_struct *sis, struct file *f) > int (*swap_deactivate)(struct file *); > int (*swap_rw)(struct kiocb *iocb, struct iov_iter *iter); > > diff --git a/Documentation/filesystems/vfs.rst > b/Documentation/filesystems/vfs.rst > index 7c753148af88..4092b2149a5d 100644 > --- a/Documentation/filesystems/vfs.rst > +++ b/Documentation/filesystems/vfs.rst > @@ -774,7 +774,7 @@ cache in your filesystem. The following members are > defined: > size_t count); > void (*is_dirty_writeback)(struct folio *, bool *, bool *); > int (*error_remove_folio)(struct mapping *mapping, struct folio > *); > - int (*swap_activate)(struct swap_info_struct *sis, struct file > *f, sector_t *span) > + int (*swap_activate)(struct swap_info_struct *sis, struct file > *f); > int (*swap_deactivate)(struct file *); > int (*swap_rw)(struct kiocb *iocb, struct iov_iter *iter); > }; > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index 906d5c21ebc4..198d87e6f19a 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -10204,51 +10204,17 @@ struct btrfs_swap_info { > u64 start; > u64 block_start; > u64 block_len; > - u64 lowest_ppage; > - u64 highest_ppage; > - unsigned long nr_pages; > - int nr_extents; > }; > > static int btrfs_add_swap_extent(struct swap_info_struct *sis, > struct btrfs_swap_info *bsi) > { > - unsigned long nr_pages; > - unsigned long max_pages; > - u64 first_ppage, first_ppage_reported, next_ppage; > - int ret; > - > - /* > - * Our swapfile may have had its size extended after the swap header was > - * written. In that case activating the swapfile should not go beyond > - * the max size set in the swap header. > - */ > - if (bsi->nr_pages >= sis->max) > - return 0; > + u64 first_ppage, next_ppage; > > - max_pages = sis->max - bsi->nr_pages; > first_ppage = PAGE_ALIGN(bsi->block_start) >> PAGE_SHIFT; > next_ppage = PAGE_ALIGN_DOWN(bsi->block_start + bsi->block_len) >> > PAGE_SHIFT; > > - if (first_ppage >= next_ppage) > - return 0; > - nr_pages = next_ppage - first_ppage; > - nr_pages = min(nr_pages, max_pages); > - > - first_ppage_reported = first_ppage; > - if (bsi->start == 0) > - first_ppage_reported++; > - if (bsi->lowest_ppage > first_ppage_reported) > - bsi->lowest_ppage = first_ppage_reported; > - if (bsi->highest_ppage < (next_ppage - 1)) > - bsi->highest_ppage = next_ppage - 1; > - > - ret = add_swap_extent(sis, bsi->nr_pages, nr_pages, first_ppage); > - if (ret < 0) > - return ret; > - bsi->nr_extents += ret; > - bsi->nr_pages += nr_pages; > - return 0; > + return add_swap_extent(sis, next_ppage - first_ppage, first_ppage); > } > > static void btrfs_swap_deactivate(struct file *file) > @@ -10259,8 +10225,7 @@ static void btrfs_swap_deactivate(struct file *file) > atomic_dec(&BTRFS_I(inode)->root->nr_swapfiles); > } > > -static int btrfs_swap_activate(struct swap_info_struct *sis, struct file > *file, > - sector_t *span) > +static int btrfs_swap_activate(struct swap_info_struct *sis, struct file > *file) > { > struct inode *inode = file_inode(file); > struct btrfs_root *root = BTRFS_I(inode)->root; > @@ -10269,9 +10234,7 @@ static int btrfs_swap_activate(struct > swap_info_struct *sis, struct file *file, > struct extent_state *cached_state = NULL; > struct btrfs_chunk_map *map = NULL; > struct btrfs_device *device = NULL; > - struct btrfs_swap_info bsi = { > - .lowest_ppage = (sector_t)-1ULL, > - }; > + struct btrfs_swap_info bsi = {}; > struct btrfs_backref_share_check_ctx *backref_ctx = NULL; > struct btrfs_path *path = NULL; > int ret = 0; > @@ -10570,23 +10533,16 @@ static int btrfs_swap_activate(struct > swap_info_struct *sis, struct file *file, > up_write(&BTRFS_I(inode)->i_mmap_lock); > btrfs_free_backref_share_ctx(backref_ctx); > btrfs_free_path(path); > - if (ret) > - return ret; > - > - if (device) > + if (!ret && device) > sis->bdev = device->bdev; > - *span = bsi.highest_ppage - bsi.lowest_ppage + 1; > - sis->max = bsi.nr_pages; > - sis->pages = bsi.nr_pages - 1; > - return bsi.nr_extents; > + return ret; > } > #else > static void btrfs_swap_deactivate(struct file *file) > { > } > > -static int btrfs_swap_activate(struct swap_info_struct *sis, struct file > *file, > - sector_t *span) > +static int btrfs_swap_activate(struct swap_info_struct *sis, struct file > *file) > { > return -EOPNOTSUPP; > } > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index c2c2d6ac7f3d..ca7bac4a8b4a 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -3940,10 +3940,9 @@ static bool ext4_dirty_folio(struct address_space > *mapping, struct folio *folio) > } > > static int ext4_iomap_swap_activate(struct swap_info_struct *sis, > - struct file *file, sector_t *span) > + struct file *file) > { > - return iomap_swapfile_activate(sis, file, span, > - &ext4_iomap_report_ops); > + return iomap_swapfile_activate(sis, file, &ext4_iomap_report_ops); > } > > static const struct address_space_operations ext4_aops = { > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 8d4f1e75dee3..86fabacc67e6 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -4249,7 +4249,7 @@ static int f2fs_migrate_blocks(struct inode *inode, > block_t start_blk, > } > > static int check_swap_activate(struct swap_info_struct *sis, > - struct file *swap_file, sector_t *span) > + struct file *swap_file) > { > struct address_space *mapping = swap_file->f_mapping; > struct inode *inode = mapping->host; > @@ -4257,9 +4257,6 @@ static int check_swap_activate(struct swap_info_struct > *sis, > block_t cur_lblock; > block_t last_lblock; > block_t pblock; > - block_t lowest_pblock = -1; > - block_t highest_pblock = 0; > - int nr_extents = 0; > unsigned int nr_pblocks; > unsigned int blks_per_sec = BLKS_PER_SEC(sbi); > unsigned int not_aligned = 0; > @@ -4272,7 +4269,7 @@ static int check_swap_activate(struct swap_info_struct > *sis, > cur_lblock = 0; > last_lblock = F2FS_BYTES_TO_BLK(i_size_read(inode)); > > - while (cur_lblock < last_lblock && cur_lblock < sis->max) { > + while (cur_lblock < last_lblock) { > struct f2fs_map_blocks map; > bool last_extent = false; > retry: > @@ -4307,8 +4304,6 @@ static int check_swap_activate(struct swap_info_struct > *sis, > not_aligned++; > > nr_pblocks = roundup(nr_pblocks, blks_per_sec); > - if (cur_lblock + nr_pblocks > sis->max) > - nr_pblocks -= blks_per_sec; > > /* this extent is last one */ > if (!nr_pblocks) { > @@ -4328,31 +4323,14 @@ static int check_swap_activate(struct > swap_info_struct *sis, > goto retry; > } > > - if (cur_lblock + nr_pblocks >= sis->max) > - nr_pblocks = sis->max - cur_lblock; > - > - if (cur_lblock) { /* exclude the header page */ > - if (pblock < lowest_pblock) > - lowest_pblock = pblock; > - if (pblock + nr_pblocks - 1 > highest_pblock) > - highest_pblock = pblock + nr_pblocks - 1; > - } > - > /* > * We found a PAGE_SIZE-length, PAGE_SIZE-aligned run of blocks > */ > - ret = add_swap_extent(sis, cur_lblock, nr_pblocks, pblock); > + ret = add_swap_extent(sis, nr_pblocks, pblock); > if (ret < 0) > goto out; > - nr_extents += ret; > cur_lblock += nr_pblocks; > } > - ret = nr_extents; > - *span = 1 + highest_pblock - lowest_pblock; > - if (cur_lblock == 0) > - cur_lblock = 1; /* force Empty message */ > - sis->max = cur_lblock; > - sis->pages = cur_lblock - 1; > out: > if (not_aligned) > f2fs_warn(sbi, "Swapfile (%u) is not align to section: 1) > creat(), 2) ioctl(F2FS_IOC_SET_PIN_FILE), 3) fallocate(%lu * N)", > @@ -4360,8 +4338,7 @@ static int check_swap_activate(struct swap_info_struct > *sis, > return ret; > } > > -static int f2fs_swap_activate(struct swap_info_struct *sis, struct file > *file, > - sector_t *span) > +static int f2fs_swap_activate(struct swap_info_struct *sis, struct file > *file) > { > struct inode *inode = file_inode(file); > struct f2fs_sb_info *sbi = F2FS_I_SB(inode); > @@ -4391,14 +4368,14 @@ static int f2fs_swap_activate(struct swap_info_struct > *sis, struct file *file, > > f2fs_precache_extents(inode); > > - ret = check_swap_activate(sis, file, span); > + ret = check_swap_activate(sis, file); > if (ret < 0) > return ret; > > stat_inc_swapfile_inode(inode); > set_inode_flag(inode, FI_PIN_FILE); > f2fs_update_time(sbi, REQ_TIME); > - return ret; > + return 0; > } > > static void f2fs_swap_deactivate(struct file *file) > @@ -4409,8 +4386,7 @@ static void f2fs_swap_deactivate(struct file *file) > clear_inode_flag(inode, FI_PIN_FILE); > } > #else > -static int f2fs_swap_activate(struct swap_info_struct *sis, struct file > *file, > - sector_t *span) > +static int f2fs_swap_activate(struct swap_info_struct *sis, struct file > *file) > { > return -EOPNOTSUPP; > } > diff --git a/fs/iomap/swapfile.c b/fs/iomap/swapfile.c > index 0db77c449467..f778b2c6c922 100644 > --- a/fs/iomap/swapfile.c > +++ b/fs/iomap/swapfile.c > @@ -11,10 +11,7 @@ > 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 */ > struct file *file; > }; > > @@ -27,16 +24,8 @@ struct iomap_swapfile_info { > 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 > @@ -45,33 +34,7 @@ static int iomap_swapfile_add_extent(struct > iomap_swapfile_info *isi) > 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; > - nr_pages = min(nr_pages, max_pages); > - > - /* > - * 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; > + return add_swap_extent(isi->sis, next_ppage - first_ppage, first_ppage); > } > > static int iomap_swapfile_fail(struct iomap_swapfile_info *isi, const char > *str) > @@ -138,8 +101,7 @@ static int iomap_swapfile_iter(struct iomap_iter *iter, > * 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 file *swap_file, const struct iomap_ops *ops) > { > struct inode *inode = swap_file->f_mapping->host; > struct iomap_iter iter = { > @@ -150,7 +112,6 @@ int iomap_swapfile_activate(struct swap_info_struct *sis, > }; > struct iomap_swapfile_info isi = { > .sis = sis, > - .lowest_ppage = (sector_t)-1ULL, > .file = swap_file, > }; > int ret; > @@ -174,19 +135,6 @@ 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; > - return isi.nr_extents; > + return 0; > } > EXPORT_SYMBOL_GPL(iomap_swapfile_activate); > diff --git a/fs/nfs/file.c b/fs/nfs/file.c > index 25048a3c2364..74b401aa2b3a 100644 > --- a/fs/nfs/file.c > +++ b/fs/nfs/file.c > @@ -567,8 +567,7 @@ static int nfs_launder_folio(struct folio *folio) > return ret; > } > > -static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file, > - sector_t *span) > +static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file) > { > unsigned long blocks; > long long isize; > @@ -589,19 +588,17 @@ static int nfs_swap_activate(struct swap_info_struct > *sis, struct file *file, > ret = rpc_clnt_swap_activate(clnt); > if (ret) > return ret; > - ret = add_swap_extent(sis, 0, sis->max, 0); > + ret = add_swap_extent(sis, sis->max, 0); > if (ret < 0) { > rpc_clnt_swap_deactivate(clnt); > return ret; > } > > - *span = sis->pages; > - > if (cl->rpc_ops->enable_swap) > cl->rpc_ops->enable_swap(inode); > > sis->flags |= SWP_FS_OPS; > - return ret; > + return 0; > } > > static void nfs_swap_deactivate(struct file *file) > diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c > index 1fbf832ad165..4b7d019bc6ed 100644 > --- a/fs/ntfs/aops.c > +++ b/fs/ntfs/aops.c > @@ -271,10 +271,9 @@ static int ntfs_writepages(struct address_space *mapping, > } > > static int ntfs_swap_activate(struct swap_info_struct *sis, > - struct file *swap_file, sector_t *span) > + struct file *swap_file) > { > - return iomap_swapfile_activate(sis, swap_file, span, > - &ntfs_read_iomap_ops); > + return iomap_swapfile_activate(sis, swap_file, &ntfs_read_iomap_ops); > } > > const struct address_space_operations ntfs_aops = { > diff --git a/fs/smb/client/file.c b/fs/smb/client/file.c > index 664a2c223089..11d4655ef490 100644 > --- a/fs/smb/client/file.c > +++ b/fs/smb/client/file.c > @@ -3287,7 +3287,7 @@ void cifs_oplock_break(struct work_struct *work) > } > > static int cifs_swap_activate(struct swap_info_struct *sis, > - struct file *swap_file, sector_t *span) > + struct file *swap_file) > { > struct cifsFileInfo *cfile = swap_file->private_data; > struct inode *inode = swap_file->f_mapping->host; > @@ -3308,7 +3308,6 @@ static int cifs_swap_activate(struct swap_info_struct > *sis, > pr_warn("swap activate: swapfile has holes\n"); > return -EINVAL; > } > - *span = sis->pages; > > pr_warn_once("Swap support over SMB3 is experimental\n"); > > @@ -3329,7 +3328,7 @@ static int cifs_swap_activate(struct swap_info_struct > *sis, > */ > > sis->flags |= SWP_FS_OPS; > - return add_swap_extent(sis, 0, sis->max, 0); > + return add_swap_extent(sis, sis->max, 0); > } > > static void cifs_swap_deactivate(struct file *file) > diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c > index f279055fcea0..1e8662e0e7cd 100644 > --- a/fs/xfs/xfs_aops.c > +++ b/fs/xfs/xfs_aops.c > @@ -799,8 +799,7 @@ xfs_vm_readahead( > static int > xfs_vm_swap_activate( > struct swap_info_struct *sis, > - struct file *swap_file, > - sector_t *span) > + struct file *swap_file) > { > struct xfs_inode *ip = XFS_I(file_inode(swap_file)); > > @@ -838,8 +837,7 @@ xfs_vm_swap_activate( > */ > sis->bdev = xfs_inode_buftarg(ip)->bt_bdev; > > - return iomap_swapfile_activate(sis, swap_file, span, > - &xfs_read_iomap_ops); > + return iomap_swapfile_activate(sis, swap_file, &xfs_read_iomap_ops); > } > > const struct address_space_operations xfs_address_space_operations = { > diff --git a/fs/zonefs/file.c b/fs/zonefs/file.c > index 5ada33f70bb4..214e4bf8e30a 100644 > --- a/fs/zonefs/file.c > +++ b/fs/zonefs/file.c > @@ -168,7 +168,7 @@ static int zonefs_writepages(struct address_space > *mapping, > } > > static int zonefs_swap_activate(struct swap_info_struct *sis, > - struct file *swap_file, sector_t *span) > + struct file *swap_file) > { > struct inode *inode = file_inode(swap_file); > > @@ -178,8 +178,7 @@ static int zonefs_swap_activate(struct swap_info_struct > *sis, > return -EINVAL; > } > > - return iomap_swapfile_activate(sis, swap_file, span, > - &zonefs_read_iomap_ops); > + return iomap_swapfile_activate(sis, swap_file, &zonefs_read_iomap_ops); > } > > const struct address_space_operations zonefs_file_aops = { > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 11559c513dfb..b8b6f7a38f4d 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -435,8 +435,7 @@ struct address_space_operations { > int (*error_remove_folio)(struct address_space *, struct folio *); > > /* swapfile support */ > - int (*swap_activate)(struct swap_info_struct *sis, struct file *file, > - sector_t *span); > + int (*swap_activate)(struct swap_info_struct *sis, struct file *file); > void (*swap_deactivate)(struct file *file); > int (*swap_rw)(struct kiocb *iocb, struct iov_iter *iter); > }; > diff --git a/include/linux/iomap.h b/include/linux/iomap.h > index 2c5685adf3a9..d82126e3d086 100644 > --- a/include/linux/iomap.h > +++ b/include/linux/iomap.h > @@ -604,10 +604,9 @@ struct file; > struct swap_info_struct; > > int iomap_swapfile_activate(struct swap_info_struct *sis, > - struct file *swap_file, sector_t *pagespan, > - const struct iomap_ops *ops); > + struct file *swap_file, const struct iomap_ops *ops); > #else > -# define iomap_swapfile_activate(sis, swapfile, pagespan, ops) (-EIO) > +# define iomap_swapfile_activate(sis, swapfile, ops) (-EIO) > #endif /* CONFIG_SWAP */ > > extern struct bio_set iomap_ioend_bioset; > diff --git a/include/linux/swap.h b/include/linux/swap.h > index 7a09df6977a5..b8dfe2c6bc98 100644 > --- a/include/linux/swap.h > +++ b/include/linux/swap.h > @@ -403,10 +403,9 @@ extern void __meminit kswapd_stop(int nid); > > #ifdef CONFIG_SWAP > > -int add_swap_extent(struct swap_info_struct *sis, unsigned long start_page, > - unsigned long nr_pages, sector_t start_block); > -int generic_swapfile_activate(struct swap_info_struct *, struct file *, > - sector_t *); > +int add_swap_extent(struct swap_info_struct *sis, unsigned long nr_pages, > + sector_t start_block); > +int generic_swapfile_activate(struct swap_info_struct *, struct file *); > > static inline unsigned long total_swapcache_pages(void) > { > @@ -528,8 +527,8 @@ static inline bool folio_free_swap(struct folio *folio) > } > > static inline int add_swap_extent(struct swap_info_struct *sis, > - unsigned long start_page, > - unsigned long nr_pages, sector_t start_block) > + unsigned long start_page, unsigned long nr_pages, > + sector_t start_block) > { > return -EINVAL; > } > diff --git a/mm/page_io.c b/mm/page_io.c > index 70cea9e24d2f..f30f36ec1ed0 100644 > --- a/mm/page_io.c > +++ b/mm/page_io.c > @@ -76,19 +76,14 @@ static void end_swap_bio_read(struct bio *bio) > } > > int generic_swapfile_activate(struct swap_info_struct *sis, > - struct file *swap_file, > - sector_t *span) > + struct file *swap_file) > { > struct address_space *mapping = swap_file->f_mapping; > struct inode *inode = mapping->host; > unsigned blocks_per_page; > - unsigned long page_no; > unsigned blkbits; > sector_t probe_block; > sector_t last_block; > - sector_t lowest_block = -1; > - sector_t highest_block = 0; > - int nr_extents = 0; > int ret; > > blkbits = inode->i_blkbits; > @@ -99,10 +94,8 @@ int generic_swapfile_activate(struct swap_info_struct *sis, > * to be very smart. > */ > probe_block = 0; > - page_no = 0; > last_block = i_size_read(inode) >> blkbits; > - while ((probe_block + blocks_per_page) <= last_block && > - page_no < sis->max) { > + while ((probe_block + blocks_per_page) <= last_block) { > unsigned block_in_page; > sector_t first_block; > > @@ -137,38 +130,22 @@ int generic_swapfile_activate(struct swap_info_struct > *sis, > } > } > > - first_block >>= (PAGE_SHIFT - blkbits); > - if (page_no) { /* exclude the header page */ > - if (first_block < lowest_block) > - lowest_block = first_block; > - if (first_block > highest_block) > - highest_block = first_block; > - } > - > /* > * We found a PAGE_SIZE-length, PAGE_SIZE-aligned run of blocks > */ > - ret = add_swap_extent(sis, page_no, 1, first_block); > + ret = add_swap_extent(sis, 1, > + first_block >> (PAGE_SHIFT - blkbits)); > if (ret < 0) > - goto out; > - nr_extents += ret; > - page_no++; > + return ret; > probe_block += blocks_per_page; > reprobe: > continue; > } > - ret = nr_extents; > - *span = 1 + highest_block - lowest_block; > - if (page_no == 0) > - page_no = 1; /* force Empty message */ > - sis->max = page_no; > - sis->pages = page_no - 1; > -out: > - return ret; > + return 0; > + > bad_bmap: > pr_err("swapon: swapfile has holes\n"); > - ret = -EINVAL; > - goto out; > + return -EINVAL; > } > > static bool is_folio_zero_filled(struct folio *folio) > diff --git a/mm/swapfile.c b/mm/swapfile.c > index f7ebd97e28a3..158620fd2978 100644 > --- a/mm/swapfile.c > +++ b/mm/swapfile.c > @@ -2704,15 +2704,21 @@ static void destroy_swap_extents(struct > swap_info_struct *sis, > * Add a block range (and the corresponding page range) into this swapdev's > * extent tree. > * > - * This function rather assumes that it is called in ascending page order. > + * Note that start_block is in units of PAGE_SIZE and not actually in block > + * layer sectors as the sector_t would suggest. > */ > int > -add_swap_extent(struct swap_info_struct *sis, unsigned long start_page, > - unsigned long nr_pages, sector_t start_block) > +add_swap_extent(struct swap_info_struct *sis, unsigned long nr_pages, > + sector_t start_block) > { > struct rb_node **link = &sis->swap_extent_root.rb_node, *parent = NULL; > struct swap_extent *se; > - struct swap_extent *new_se; > + > + if (!nr_pages) > + return 0; > + if (unlikely(sis->pages >= sis->max)) > + return 0; > + nr_pages = min(nr_pages, sis->max - sis->pages); > > /* > * place the new node at the right most since the > @@ -2725,25 +2731,25 @@ add_swap_extent(struct swap_info_struct *sis, > unsigned long start_page, > > if (parent) { > se = rb_entry(parent, struct swap_extent, rb_node); > - BUG_ON(se->start_page + se->nr_pages != start_page); > - if (se->start_block + se->nr_pages == start_block) { > - /* Merge it */ > - se->nr_pages += nr_pages; > - return 0; > - } > + if (WARN_ON_ONCE(se->start_page + se->nr_pages != sis->pages)) > + return -EINVAL; > + if (se->start_block + se->nr_pages == start_block) > + goto add; > } > > /* No merge, insert a new extent. */ > - new_se = kmalloc_obj(*se); > - if (new_se == NULL) > + se = kzalloc_obj(*se); > + if (!se) > return -ENOMEM; > - new_se->start_page = start_page; > - new_se->nr_pages = nr_pages; > - new_se->start_block = start_block; > - > - rb_link_node(&new_se->rb_node, parent, link); > - rb_insert_color(&new_se->rb_node, &sis->swap_extent_root); > - return 1; > + rb_link_node(&se->rb_node, parent, link); > + rb_insert_color(&se->rb_node, &sis->swap_extent_root); > + > + se->start_page = sis->pages; > + se->start_block = start_block; > +add: > + se->nr_pages += nr_pages; > + sis->pages += nr_pages; > + return 0; > } > EXPORT_SYMBOL_GPL(add_swap_extent); > > @@ -2775,20 +2781,17 @@ EXPORT_SYMBOL_GPL(add_swap_extent); > * extents in the rbtree. - akpm. > */ > static int setup_swap_extents(struct swap_info_struct *sis, > - struct file *swap_file, sector_t *span) > + struct file *swap_file) > { > struct address_space *mapping = swap_file->f_mapping; > struct inode *inode = mapping->host; > int ret; > > - if (S_ISBLK(inode->i_mode)) { > - ret = add_swap_extent(sis, 0, sis->max, 0); > - *span = sis->pages; > - return ret; > - } > + if (S_ISBLK(inode->i_mode)) > + return add_swap_extent(sis, sis->max, 0); > > if (mapping->a_ops->swap_activate) { > - ret = mapping->a_ops->swap_activate(sis, swap_file, span); > + ret = mapping->a_ops->swap_activate(sis, swap_file); > if (ret < 0) > return ret; > sis->flags |= SWP_ACTIVATED; > @@ -2800,7 +2803,7 @@ static int setup_swap_extents(struct swap_info_struct > *sis, > return ret; > } > > - return generic_swapfile_activate(sis, swap_file, span); > + return generic_swapfile_activate(sis, swap_file); > } > > static void _enable_swap_info(struct swap_info_struct *si) > @@ -3428,6 +3431,40 @@ static int setup_swap_clusters_info(struct > swap_info_struct *si, > return err; > } > > +static void swap_print_info(struct swap_info_struct *si, const char *name) > +{ > + unsigned int nr_extents = 0; > + u64 lowest_ppage = (u64)-1; > + u64 highest_ppage = 0; > + struct swap_extent *se; > + > + /* > + * Calculate how much swap space we're adding; the first page contains > + * the swap header and doesn't count. > + */ > + for (se = first_se(si); se; se = next_se(se)) { > + u64 first_ppage = se->start_block; > + u64 next_ppage = se->start_block + se->nr_pages; > + > + if (se->start_page == 0) > + first_ppage++; > + > + if (lowest_ppage > first_ppage) > + lowest_ppage = first_ppage; > + if (highest_ppage < next_ppage - 1) > + highest_ppage = next_ppage - 1; > + nr_extents++; > + } > + > + pr_info("Adding %uk swap on %s. Priority:%d extents:%d across:%lluk > %s%s%s%s\n", > + K(si->pages), name, si->prio, nr_extents, > + K(highest_ppage - lowest_ppage), > + (si->flags & SWP_SOLIDSTATE) ? "SS" : "", > + (si->flags & SWP_DISCARDABLE) ? "D" : "", > + (si->flags & SWP_AREA_DISCARD) ? "s" : "", > + (si->flags & SWP_PAGE_DISCARD) ? "c" : ""); > +} > + > SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) > { > struct swap_info_struct *si; > @@ -3437,8 +3474,6 @@ SYSCALL_DEFINE2(swapon, const char __user *, > specialfile, int, swap_flags) > int prio; > int error; > union swap_header *swap_header; > - int nr_extents; > - sector_t span; > struct folio *folio = NULL; > struct inode *inode = NULL; > bool inced_nr_rotate_swap = false; > @@ -3510,24 +3545,25 @@ SYSCALL_DEFINE2(swapon, const char __user *, > specialfile, int, swap_flags) > } > swap_header = kmap_local_folio(folio, 0); > > + si->pages = 0; > si->max = read_swap_header(si, swap_header, inode); > if (unlikely(!si->max)) { > error = -EINVAL; > goto bad_swap_unlock_inode; > } > > - si->pages = si->max - 1; > - nr_extents = setup_swap_extents(si, swap_file, &span); > - if (nr_extents < 0) { > - error = nr_extents; > + error = setup_swap_extents(si, swap_file); > + if (error < 0) > goto bad_swap_unlock_inode; > - } > - if (si->pages != si->max - 1) { > - pr_err("swap:%u != (max:%u - 1)\n", si->pages, si->max); > + if (si->pages != si->max) { > + pr_err("swap:%u != (max:%u)\n", si->pages, si->max); > error = -EINVAL; > goto bad_swap_unlock_inode; > } > > + /* Remove the first page countaining the swap header. */ > + si->pages--; > + > /* Set up the swap cluster info */ > error = setup_swap_clusters_info(si, swap_header); > if (error) > @@ -3624,13 +3660,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, > specialfile, int, swap_flags) > /* Sets SWP_WRITEOK, resurrect the percpu ref, expose the swap device */ > enable_swap_info(si); > > - pr_info("Adding %uk swap on %s. Priority:%d extents:%d across:%lluk > %s%s%s%s\n", > - K(si->pages), name->name, si->prio, nr_extents, > - K((unsigned long long)span), > - (si->flags & SWP_SOLIDSTATE) ? "SS" : "", > - (si->flags & SWP_DISCARDABLE) ? "D" : "", > - (si->flags & SWP_AREA_DISCARD) ? "s" : "", > - (si->flags & SWP_PAGE_DISCARD) ? "c" : ""); > + swap_print_info(si, name->name); > > mutex_unlock(&swapon_mutex); > atomic_inc(&proc_poll_event); > -- > 2.53.0 > > _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
