diff options
| author |   Murphy Zhou <jencce.kernel@gmail.com> | 2020-01-17 20:49:29 +0800 |
|---|---|---|
| committer |   Miklos Szeredi <mszeredi@redhat.com> | 2020-01-24 16:28:15 +0100 |
| commit | 1a980b8cbf0059a5308eea61522f232fd03002e2 (patch) | |
| tree | 9b6f1e8e798a6ca77486949e4d920dac1fcc8e7d /fs | |
| parent | ovl: implement async IO routines (diff) | |
| download | linux-dev-1a980b8cbf0059a5308eea61522f232fd03002e2.tar.xz linux-dev-1a980b8cbf0059a5308eea61522f232fd03002e2.zip | |
ovl: add splice file read write helper
Now overlayfs falls back to use default file splice read
and write, which is not compatiple with overlayfs, returning
EFAULT. xfstests generic/591 can reproduce part of this.
Tested this patch with xfstests auto group tests.
Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/overlayfs/file.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 4d1796c37dfd..67ef4c8cfdc7 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -9,6 +9,9 @@ #include <linux/xattr.h> #include <linux/uio.h> #include <linux/uaccess.h> +#include <linux/splice.h> +#include <linux/mm.h> +#include <linux/fs.h> #include "overlayfs.h" struct ovl_aio_req { @@ -362,6 +365,48 @@ out_unlock: return ret; } +static ssize_t ovl_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags) +{ + ssize_t ret; + struct fd real; + const struct cred *old_cred; + + ret = ovl_real_fdget(in, &real); + if (ret) + return ret; + + old_cred = ovl_override_creds(file_inode(in)->i_sb); + ret = generic_file_splice_read(real.file, ppos, pipe, len, flags); + revert_creds(old_cred); + + ovl_file_accessed(in); + fdput(real); + return ret; +} + +static ssize_t +ovl_splice_write(struct pipe_inode_info *pipe, struct file *out, + loff_t *ppos, size_t len, unsigned int flags) +{ + struct fd real; + const struct cred *old_cred; + ssize_t ret; + + ret = ovl_real_fdget(out, &real); + if (ret) + return ret; + + old_cred = ovl_override_creds(file_inode(out)->i_sb); + ret = iter_file_splice_write(pipe, real.file, ppos, len, flags); + revert_creds(old_cred); + + ovl_file_accessed(out); + fdput(real); + return ret; +} + static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync) { struct fd real; @@ -718,6 +763,8 @@ const struct file_operations ovl_file_operations = { .fadvise = ovl_fadvise, .unlocked_ioctl = ovl_ioctl, .compat_ioctl = ovl_compat_ioctl, + .splice_read = ovl_splice_read, + .splice_write = ovl_splice_write, .copy_file_range = ovl_copy_file_range, .remap_file_range = ovl_remap_file_range, |