From 42ec3d4c02187a18e27ff94b409ec27234bf2ffd Mon Sep 17 00:00:00 2001 From: Darrick J. Wong Date: Tue, 30 Oct 2018 10:41:49 +1100 Subject: vfs: make remap_file_range functions take and return bytes completed Change the remap_file_range functions to take a number of bytes to operate upon and return the number of bytes they operated on. This is a requirement for allowing fs implementations to return short clone/dedupe results to the user, which will enable us to obey resource limits in a graceful manner. A subsequent patch will enable copy_file_range to signal to the ->clone_file_range implementation that it can handle a short length, which will be returned in the function's return value. For now the short return is not implemented anywhere so the behavior won't change -- either copy_file_range manages to clone the entire range or it tries an alternative. Neither clone ioctl can take advantage of this, alas. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Signed-off-by: Dave Chinner --- fs/ioctl.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'fs/ioctl.c') diff --git a/fs/ioctl.c b/fs/ioctl.c index 2005529af560..72537b68c272 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -223,6 +223,7 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, u64 off, u64 olen, u64 destoff) { struct fd src_file = fdget(srcfd); + loff_t cloned; int ret; if (!src_file.file) @@ -230,7 +231,14 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, ret = -EXDEV; if (src_file.file->f_path.mnt != dst_file->f_path.mnt) goto fdput; - ret = vfs_clone_file_range(src_file.file, off, dst_file, destoff, olen); + cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff, + olen); + if (cloned < 0) + ret = cloned; + else if (olen && cloned != olen) + ret = -EINVAL; + else + ret = 0; fdput: fdput(src_file); return ret; -- cgit v1.2.3-55-g7522 From 452ce65951a2f0719e4e119ecca134c06cfe22ee Mon Sep 17 00:00:00 2001 From: Darrick J. Wong Date: Tue, 30 Oct 2018 10:41:56 +1100 Subject: vfs: plumb remap flags through the vfs clone functions Plumb a remap_flags argument through the {do,vfs}_clone_file_range functions so that clone can take advantage of it. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Signed-off-by: Dave Chinner --- fs/ioctl.c | 2 +- fs/nfsd/vfs.c | 2 +- fs/overlayfs/copy_up.c | 2 +- fs/overlayfs/file.c | 6 +++--- fs/read_write.c | 13 +++++++++---- include/linux/fs.h | 4 ++-- 6 files changed, 17 insertions(+), 12 deletions(-) (limited to 'fs/ioctl.c') diff --git a/fs/ioctl.c b/fs/ioctl.c index 72537b68c272..505275ec5596 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -232,7 +232,7 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, if (src_file.file->f_path.mnt != dst_file->f_path.mnt) goto fdput; cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff, - olen); + olen, 0); if (cloned < 0) ret = cloned; else if (olen && cloned != olen) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index ac6cb6101cbe..726fc5b2b27a 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -543,7 +543,7 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst, { loff_t cloned; - cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count); + cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, 0); if (count && cloned != count) cloned = -EINVAL; return nfserrno(cloned < 0 ? cloned : 0); diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 8750b7235516..5f82fece64a0 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -142,7 +142,7 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len) } /* Try to use clone_file_range to clone up within the same fs */ - cloned = do_clone_file_range(old_file, 0, new_file, 0, len); + cloned = do_clone_file_range(old_file, 0, new_file, 0, len, 0); if (cloned == len) goto out; /* Couldn't clone, so now we try to copy the data */ diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 6c3fec6168e9..0393815c8971 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -462,7 +462,7 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in, case OVL_CLONE: ret = vfs_clone_file_range(real_in.file, pos_in, - real_out.file, pos_out, len); + real_out.file, pos_out, len, flags); break; case OVL_DEDUPE: @@ -512,8 +512,8 @@ static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in, !ovl_inode_upper(file_inode(file_out)))) return -EPERM; - return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, 0, - op); + return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, + remap_flags, op); } const struct file_operations ovl_file_operations = { diff --git a/fs/read_write.c b/fs/read_write.c index 356641afa487..0d1ac1b9bc22 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1848,12 +1848,15 @@ int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, EXPORT_SYMBOL(generic_remap_file_range_prep); loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, loff_t len) + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags) { struct inode *inode_in = file_inode(file_in); struct inode *inode_out = file_inode(file_out); loff_t ret; + WARN_ON_ONCE(remap_flags); + if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) return -EISDIR; if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) @@ -1884,7 +1887,7 @@ loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, return ret; ret = file_in->f_op->remap_file_range(file_in, pos_in, - file_out, pos_out, len, 0); + file_out, pos_out, len, remap_flags); if (ret < 0) return ret; @@ -1895,12 +1898,14 @@ loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, EXPORT_SYMBOL(do_clone_file_range); loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, loff_t len) + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags) { loff_t ret; file_start_write(file_out); - ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len); + ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len, + remap_flags); file_end_write(file_out); return ret; diff --git a/include/linux/fs.h b/include/linux/fs.h index c72d8c3c065a..1c5e55d2a67d 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1848,10 +1848,10 @@ extern int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, unsigned int remap_flags); extern loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, - loff_t len); + loff_t len, unsigned int remap_flags); extern loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, - loff_t len); + loff_t len, unsigned int remap_flags); extern int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, struct inode *dest, loff_t destoff, loff_t len, bool *is_same); -- cgit v1.2.3-55-g7522