iomap: move the file mapping reporting code into a separate file

Move the file mapping reporting code (FIEMAP/FIBMAP) into a separate
file so that we can group related functions in a single file instead of
having a single enormous source file.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/iomap.c

@@ -1149,108 +1149,6 @@ vm_fault_t iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops)
 }
 EXPORT_SYMBOL_GPL(iomap_page_mkwrite);
 
-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 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,
-		loff_t start, loff_t 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_check_flags(fi, FIEMAP_FLAG_SYNC);
-	if (ret)
-		return ret;
-
-	if (fi->fi_flags & FIEMAP_FLAG_SYNC) {
-		ret = filemap_write_and_wait(inode->i_mapping);
-		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);
-
 /*
  * Seek for SEEK_DATA / SEEK_HOLE within @page, starting at @lastoff.
  * Returns true if found and updates @lastoff to the offset in file.
@@ -1999,37 +1897,3 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
 	return ret;
 }
 EXPORT_SYMBOL_GPL(iomap_dio_rw);
-
-static loff_t
-iomap_bmap_actor(struct inode *inode, loff_t pos, loff_t length,
-		void *data, struct iomap *iomap)
-{
-	sector_t *bno = data, addr;
-
-	if (iomap->type == IOMAP_MAPPED) {
-		addr = (pos - iomap->offset + iomap->addr) >> inode->i_blkbits;
-		if (addr > INT_MAX)
-			WARN(1, "would truncate bmap result\n");
-		else
-			*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);
-
-	if (filemap_write_and_wait(mapping))
-		return 0;
-
-	bno = 0;
-	iomap_apply(inode, pos, blocksize, 0, ops, &bno, iomap_bmap_actor);
-	return bno;
-}
-EXPORT_SYMBOL_GPL(iomap_bmap);

fs/iomap/Makefile

@@ -5,4 +5,7 @@
 #
 obj-$(CONFIG_FS_IOMAP)		+= iomap.o
 
+iomap-y				+= \
+					fiemap.o
+
 iomap-$(CONFIG_SWAP)		+= swapfile.o

fs/iomap/fiemap.c

+// 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 "../internal.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 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,
+		loff_t start, loff_t 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_check_flags(fi, FIEMAP_FLAG_SYNC);
+	if (ret)
+		return ret;
+
+	if (fi->fi_flags & FIEMAP_FLAG_SYNC) {
+		ret = filemap_write_and_wait(inode->i_mapping);
+		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)
+{
+	sector_t *bno = data, addr;
+
+	if (iomap->type == IOMAP_MAPPED) {
+		addr = (pos - iomap->offset + iomap->addr) >> inode->i_blkbits;
+		if (addr > INT_MAX)
+			WARN(1, "would truncate bmap result\n");
+		else
+			*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);
+
+	if (filemap_write_and_wait(mapping))
+		return 0;
+
+	bno = 0;
+	iomap_apply(inode, pos, blocksize, 0, ops, &bno, iomap_bmap_actor);
+	return bno;
+}
+EXPORT_SYMBOL_GPL(iomap_bmap);