| Message ID | 20220426174335.4004987-11-shr@fb.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | io-uring/xfs: support async buffered writes | expand |
On Tue, Apr 26, 2022 at 10:43:27AM -0700, Stefan Roesch wrote: > This modifies xfs write checks to return -EAGAIN if the request either > requires to remove privileges or needs to update the file modification > time. This is required for async buffered writes, so the request gets > handled in the io worker. > > Signed-off-by: Stefan Roesch <shr@fb.com> > --- > fs/xfs/xfs_file.c | 39 ++++++++++++++++++++++++++++++++++++++- > 1 file changed, 38 insertions(+), 1 deletion(-) > > diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c > index 5bddb1e9e0b3..6f9da1059e8b 100644 > --- a/fs/xfs/xfs_file.c > +++ b/fs/xfs/xfs_file.c > @@ -299,6 +299,43 @@ xfs_file_read_iter( > return ret; > } > > +static int xfs_file_modified(struct file *file, int flags) > +{ > + int ret; > + struct dentry *dentry = file_dentry(file); > + struct inode *inode = file_inode(file); > + struct timespec64 now = current_time(inode); > + > + /* > + * Clear the security bits if the process is not being run by root. > + * This keeps people from modifying setuid and setgid binaries. > + */ > + ret = need_file_remove_privs(inode, dentry); > + if (ret < 0) { > + return ret; > + } else if (ret > 0) { > + if (flags & IOCB_NOWAIT) > + return -EAGAIN; > + > + ret = do_file_remove_privs(file, inode, dentry, ret); > + if (ret) > + return ret; > + } > + > + ret = need_file_update_time(inode, file, &now); > + if (ret <= 0) > + return ret; > + if (flags & IOCB_NOWAIT) { > + if (IS_PENDING_TIME(inode)) > + return 0; > + > + inode->i_flags |= S_PENDING_TIME; > + return -EAGAIN; > + } > + > + return do_file_update_time(inode, file, &now, ret); > +} This has nothing XFS specific in it. It belongs in the VFS code. -Dave.
On Tue, Apr 26, 2022 at 10:43:27AM -0700, Stefan Roesch wrote: > This modifies xfs write checks to return -EAGAIN if the request either > requires to remove privileges or needs to update the file modification > time. This is required for async buffered writes, so the request gets > handled in the io worker. > > Signed-off-by: Stefan Roesch <shr@fb.com> > --- > fs/xfs/xfs_file.c | 39 ++++++++++++++++++++++++++++++++++++++- > 1 file changed, 38 insertions(+), 1 deletion(-) > > diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c > index 5bddb1e9e0b3..6f9da1059e8b 100644 > --- a/fs/xfs/xfs_file.c > +++ b/fs/xfs/xfs_file.c > @@ -299,6 +299,43 @@ xfs_file_read_iter( > return ret; > } > > +static int xfs_file_modified(struct file *file, int flags) This should probably be in fs/inode.c as: int file_modified_async(struct file *file, int flags) and then file_modified() can simply become: int file_modified(struct file *file) { return file_modified_async(file, 0); } or even: int file_modified_async(struct file *file, bool async) int file_modified(struct file *file) { return file_modified_async(file, false); } to avoid piecing this together specifically in xfs (as Dave mentioned this is all pretty generic).
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 5bddb1e9e0b3..6f9da1059e8b 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -299,6 +299,43 @@ xfs_file_read_iter( return ret; } +static int xfs_file_modified(struct file *file, int flags) +{ + int ret; + struct dentry *dentry = file_dentry(file); + struct inode *inode = file_inode(file); + struct timespec64 now = current_time(inode); + + /* + * Clear the security bits if the process is not being run by root. + * This keeps people from modifying setuid and setgid binaries. + */ + ret = need_file_remove_privs(inode, dentry); + if (ret < 0) { + return ret; + } else if (ret > 0) { + if (flags & IOCB_NOWAIT) + return -EAGAIN; + + ret = do_file_remove_privs(file, inode, dentry, ret); + if (ret) + return ret; + } + + ret = need_file_update_time(inode, file, &now); + if (ret <= 0) + return ret; + if (flags & IOCB_NOWAIT) { + if (IS_PENDING_TIME(inode)) + return 0; + + inode->i_flags |= S_PENDING_TIME; + return -EAGAIN; + } + + return do_file_update_time(inode, file, &now, ret); +} + /* * Common pre-write limit and setup checks. * @@ -410,7 +447,7 @@ xfs_file_write_checks( spin_unlock(&ip->i_flags_lock); out: - return file_modified(file); + return xfs_file_modified(file, iocb->ki_flags); } static int
This modifies xfs write checks to return -EAGAIN if the request either requires to remove privileges or needs to update the file modification time. This is required for async buffered writes, so the request gets handled in the io worker. Signed-off-by: Stefan Roesch <shr@fb.com> --- fs/xfs/xfs_file.c | 39 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 38 insertions(+), 1 deletion(-)