diff options
Diffstat (limited to 'fs/iomap/fiemap.c')
-rw-r--r-- | fs/iomap/fiemap.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/fs/iomap/fiemap.c b/fs/iomap/fiemap.c new file mode 100644 index 000000000..aab070df4 --- /dev/null +++ b/fs/iomap/fiemap.c @@ -0,0 +1,140 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2016-2018 Christoph Hellwig. + */ +#include <linux/module.h> +#include <linux/compiler.h> +#include <linux/fs.h> +#include <linux/iomap.h> +#include <linux/fiemap.h> + +struct fiemap_ctx { + struct fiemap_extent_info *fi; + struct iomap prev; +}; + +static int iomap_to_fiemap(struct fiemap_extent_info *fi, + struct iomap *iomap, u32 flags) +{ + switch (iomap->type) { + case IOMAP_HOLE: + /* skip holes */ + return 0; + case IOMAP_DELALLOC: + flags |= FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN; + break; + case IOMAP_MAPPED: + break; + case IOMAP_UNWRITTEN: + flags |= FIEMAP_EXTENT_UNWRITTEN; + break; + case IOMAP_INLINE: + flags |= FIEMAP_EXTENT_DATA_INLINE; + break; + } + + if (iomap->flags & IOMAP_F_MERGED) + flags |= FIEMAP_EXTENT_MERGED; + if (iomap->flags & IOMAP_F_SHARED) + flags |= FIEMAP_EXTENT_SHARED; + + return fiemap_fill_next_extent(fi, iomap->offset, + iomap->addr != IOMAP_NULL_ADDR ? iomap->addr : 0, + iomap->length, flags); +} + +static loff_t +iomap_fiemap_actor(struct inode *inode, loff_t pos, loff_t length, void *data, + struct iomap *iomap, struct iomap *srcmap) +{ + struct fiemap_ctx *ctx = data; + loff_t ret = length; + + if (iomap->type == IOMAP_HOLE) + return length; + + ret = iomap_to_fiemap(ctx->fi, &ctx->prev, 0); + ctx->prev = *iomap; + switch (ret) { + case 0: /* success */ + return length; + case 1: /* extent array full */ + return 0; + default: + return ret; + } +} + +int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi, + u64 start, u64 len, const struct iomap_ops *ops) +{ + struct fiemap_ctx ctx; + loff_t ret; + + memset(&ctx, 0, sizeof(ctx)); + ctx.fi = fi; + ctx.prev.type = IOMAP_HOLE; + + ret = fiemap_prep(inode, fi, start, &len, 0); + if (ret) + return ret; + + while (len > 0) { + ret = iomap_apply(inode, start, len, IOMAP_REPORT, ops, &ctx, + iomap_fiemap_actor); + /* inode with no (attribute) mapping will give ENOENT */ + if (ret == -ENOENT) + break; + if (ret < 0) + return ret; + if (ret == 0) + break; + + start += ret; + len -= ret; + } + + if (ctx.prev.type != IOMAP_HOLE) { + ret = iomap_to_fiemap(fi, &ctx.prev, FIEMAP_EXTENT_LAST); + if (ret < 0) + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(iomap_fiemap); + +static loff_t +iomap_bmap_actor(struct inode *inode, loff_t pos, loff_t length, + void *data, struct iomap *iomap, struct iomap *srcmap) +{ + sector_t *bno = data, addr; + + if (iomap->type == IOMAP_MAPPED) { + addr = (pos - iomap->offset + iomap->addr) >> inode->i_blkbits; + *bno = addr; + } + return 0; +} + +/* legacy ->bmap interface. 0 is the error return (!) */ +sector_t +iomap_bmap(struct address_space *mapping, sector_t bno, + const struct iomap_ops *ops) +{ + struct inode *inode = mapping->host; + loff_t pos = bno << inode->i_blkbits; + unsigned blocksize = i_blocksize(inode); + int ret; + + if (filemap_write_and_wait(mapping)) + return 0; + + bno = 0; + ret = iomap_apply(inode, pos, blocksize, 0, ops, &bno, + iomap_bmap_actor); + if (ret) + return 0; + return bno; +} +EXPORT_SYMBOL_GPL(iomap_bmap); |