[PATCH 08/19] fuse2fs: turn on iomap for pagecache IO

["Darrick J. Wong" <djwong@kernel.org>]

From: Darrick J. Wong <djwong@kernel.org>

Turn on iomap for pagecache IO to regular files.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
---
 fuse4fs/fuse4fs.c |   61 +++++++++++++++++++++++++++++++++++++++++++++++------
 misc/fuse2fs.c    |   61 +++++++++++++++++++++++++++++++++++++++++++++++------
 2 files changed, 108 insertions(+), 14 deletions(-)


diff --git a/fuse4fs/fuse4fs.c b/fuse4fs/fuse4fs.c
index 2f95a1ecbfa330..39737c72e6133f 100644
--- a/fuse4fs/fuse4fs.c
+++ b/fuse4fs/fuse4fs.c
@@ -6219,9 +6219,6 @@ static int fuse4fs_iomap_begin_read(struct fuse4fs *ff, ext2_ino_t ino,
 				    uint64_t count, uint32_t opflags,
 				    struct fuse_file_iomap *read)
 {
-	if (!(opflags & FUSE_IOMAP_OP_DIRECT))
-		return -ENOSYS;
-
 	/* fall back to slow path for inline data reads */
 	if (inode->i_flags & EXT4_INLINE_DATA_FL)
 		return -ENOSYS;
@@ -6312,9 +6309,6 @@ static int fuse4fs_iomap_begin_write(struct fuse4fs *ff, ext2_ino_t ino,
 	off_t max_size = fuse4fs_max_file_size(ff, inode);
 	int ret;
 
-	if (!(opflags & FUSE_IOMAP_OP_DIRECT))
-		return -ENOSYS;
-
 	if (pos >= max_size)
 		return -EFBIG;
 
@@ -6410,12 +6404,51 @@ static void op_iomap_begin(fuse_req_t req, fuse_ino_t fino, uint64_t dontcare,
 		fuse_reply_iomap_begin(req, &read, NULL);
 }
 
+static int fuse4fs_iomap_append_setsize(struct fuse4fs *ff, ext2_ino_t ino,
+					loff_t newsize)
+{
+	ext2_filsys fs = ff->fs;
+	struct ext2_inode_large inode;
+	ext2_off64_t isize;
+	errcode_t err;
+
+	dbg_printf(ff, "%s: ino=%u newsize=%llu\n", __func__, ino,
+		   (unsigned long long)newsize);
+
+	err = fuse4fs_read_inode(fs, ino, &inode);
+	if (err)
+		return translate_error(fs, ino, err);
+
+	isize = EXT2_I_SIZE(&inode);
+	if (newsize <= isize)
+		return 0;
+
+	dbg_printf(ff, "%s: ino=%u oldsize=%llu newsize=%llu\n", __func__, ino,
+		   (unsigned long long)isize,
+		   (unsigned long long)newsize);
+
+	/*
+	 * XXX cheesily update the ondisk size even though we only want to do
+	 * the incore size until writeback happens
+	 */
+	err = ext2fs_inode_size_set(fs, EXT2_INODE(&inode), newsize);
+	if (err)
+		return translate_error(fs, ino, err);
+
+	err = fuse4fs_write_inode(fs, ino, &inode);
+	if (err)
+		return translate_error(fs, ino, err);
+
+	return 0;
+}
+
 static void op_iomap_end(fuse_req_t req, fuse_ino_t fino, uint64_t dontcare,
 			 off_t pos, uint64_t count, uint32_t opflags,
 			 ssize_t written, const struct fuse_file_iomap *iomap)
 {
 	struct fuse4fs *ff = fuse4fs_get(req);
 	ext2_ino_t ino;
+	int ret = 0;
 
 	FUSE4FS_CHECK_CONTEXT(req);
 	FUSE4FS_CONVERT_FINO(req, &ino, fino);
@@ -6429,7 +6462,21 @@ static void op_iomap_end(fuse_req_t req, fuse_ino_t fino, uint64_t dontcare,
 		   written,
 		   iomap->flags);
 
-	fuse_reply_err(req, 0);
+	fuse4fs_start(ff);
+
+	/* XXX is this really necessary? */
+	if ((opflags & FUSE_IOMAP_OP_WRITE) &&
+	    !(opflags & FUSE_IOMAP_OP_DIRECT) &&
+	    (iomap->flags & FUSE_IOMAP_F_SIZE_CHANGED) &&
+	    written > 0) {
+		ret = fuse4fs_iomap_append_setsize(ff, ino, pos + written);
+		if (ret)
+			goto out_unlock;
+	}
+
+out_unlock:
+	fuse4fs_finish(ff, ret);
+	fuse_reply_err(req, -ret);
 }
 
 /*
diff --git a/misc/fuse2fs.c b/misc/fuse2fs.c
index 4b64a37aa0e029..afb50a7e498694 100644
--- a/misc/fuse2fs.c
+++ b/misc/fuse2fs.c
@@ -5665,9 +5665,6 @@ static int fuse2fs_iomap_begin_read(struct fuse2fs *ff, ext2_ino_t ino,
 				    uint64_t count, uint32_t opflags,
 				    struct fuse_file_iomap *read)
 {
-	if (!(opflags & FUSE_IOMAP_OP_DIRECT))
-		return -ENOSYS;
-
 	/* fall back to slow path for inline data reads */
 	if (inode->i_flags & EXT4_INLINE_DATA_FL)
 		return -ENOSYS;
@@ -5755,9 +5752,6 @@ static int fuse2fs_iomap_begin_write(struct fuse2fs *ff, ext2_ino_t ino,
 	off_t max_size = fuse2fs_max_file_size(ff, inode);
 	int ret;
 
-	if (!(opflags & FUSE_IOMAP_OP_DIRECT))
-		return -ENOSYS;
-
 	if (pos >= max_size)
 		return -EFBIG;
 
@@ -5852,11 +5846,50 @@ static int op_iomap_begin(const char *path, uint64_t nodeid, uint64_t attr_ino,
 	return ret;
 }
 
+static int fuse2fs_iomap_append_setsize(struct fuse2fs *ff, ext2_ino_t ino,
+					loff_t newsize)
+{
+	ext2_filsys fs = ff->fs;
+	struct ext2_inode_large inode;
+	ext2_off64_t isize;
+	errcode_t err;
+
+	dbg_printf(ff, "%s: ino=%u newsize=%llu\n", __func__, ino,
+		   (unsigned long long)newsize);
+
+	err = fuse2fs_read_inode(fs, ino, &inode);
+	if (err)
+		return translate_error(fs, ino, err);
+
+	isize = EXT2_I_SIZE(&inode);
+	if (newsize <= isize)
+		return 0;
+
+	dbg_printf(ff, "%s: ino=%u oldsize=%llu newsize=%llu\n", __func__, ino,
+		   (unsigned long long)isize,
+		   (unsigned long long)newsize);
+
+	/*
+	 * XXX cheesily update the ondisk size even though we only want to do
+	 * the incore size until writeback happens
+	 */
+	err = ext2fs_inode_size_set(fs, EXT2_INODE(&inode), newsize);
+	if (err)
+		return translate_error(fs, ino, err);
+
+	err = fuse2fs_write_inode(fs, ino, &inode);
+	if (err)
+		return translate_error(fs, ino, err);
+
+	return 0;
+}
+
 static int op_iomap_end(const char *path, uint64_t nodeid, uint64_t attr_ino,
 			off_t pos, uint64_t count, uint32_t opflags,
 			ssize_t written, const struct fuse_file_iomap *iomap)
 {
 	struct fuse2fs *ff = fuse2fs_get();
+	int ret = 0;
 
 	FUSE2FS_CHECK_CONTEXT(ff);
 
@@ -5871,7 +5904,21 @@ static int op_iomap_end(const char *path, uint64_t nodeid, uint64_t attr_ino,
 		   written,
 		   iomap->flags);
 
-	return 0;
+	fuse2fs_start(ff);
+
+	/* XXX is this really necessary? */
+	if ((opflags & FUSE_IOMAP_OP_WRITE) &&
+	    !(opflags & FUSE_IOMAP_OP_DIRECT) &&
+	    (iomap->flags & FUSE_IOMAP_F_SIZE_CHANGED) &&
+	    written > 0) {
+		ret = fuse2fs_iomap_append_setsize(ff, attr_ino, pos + written);
+		if (ret)
+			goto out_unlock;
+	}
+
+out_unlock:
+	fuse2fs_finish(ff, ret);
+	return ret;
 }
 
 /*