AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-11-24 01:30:55 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity

xfs: refactor locking and unlocking two inodes against userspace IO

Browse Source 
Refactor the two functions that we use to lock and unlock two inodes to
block userspace from initiating IO against a file, whether via system
calls or mmap activity.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
This commit is contained in:
Darrick J. Wong 2020-06-29 14:47:20 -07:00
parent 451d34ee07
commit 10b4bd6c9c
3 changed files with 34 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
fs/xfs/xfs_file.c
View File

@ -1065,7 +1065,7 @@ xfs_file_remap_range(
if (mp->m_flags & XFS_MOUNT_WSYNC)
xfs_log_force_inode(dest);
out_unlock:
xfs_reflink_remap_unlock(file_in, file_out);
xfs_reflink_remap_unlock(src, dest);
if (ret)
trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_);
return remapped > 0 ? remapped : ret;

52
fs/xfs/xfs_reflink.c
View File

@ -1284,24 +1284,42 @@ xfs_iolock_two_inodes_and_break_layout(
return 0;
}
/* Unlock both inodes after they've been prepped for a range clone. */
/*
* Lock two files so that userspace cannot initiate I/O via file syscalls or
* mmap activity.
*/
static int
xfs_reflink_remap_lock(
struct xfs_inode *ip1,
struct xfs_inode *ip2)
{
int ret;
ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
if (ret)
return ret;
if (ip1 == ip2)
xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
else
xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL,
ip2, XFS_MMAPLOCK_EXCL);
return 0;
}
/* Unlock both files to allow IO and mmap activity. */
void
xfs_reflink_remap_unlock(
struct file *file_in,
struct file *file_out)
struct xfs_inode *ip1,
struct xfs_inode *ip2)
{
struct inode *inode_in = file_inode(file_in);
struct xfs_inode *src = XFS_I(inode_in);
struct inode *inode_out = file_inode(file_out);
struct xfs_inode *dest = XFS_I(inode_out);
bool same_inode = (inode_in == inode_out);
bool same_inode = (ip1 == ip2);
xfs_iunlock(dest, XFS_MMAPLOCK_EXCL);
xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
if (!same_inode)
xfs_iunlock(src, XFS_MMAPLOCK_EXCL);
inode_unlock(inode_out);
xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
inode_unlock(VFS_I(ip2));
if (!same_inode)
inode_unlock(inode_in);
inode_unlock(VFS_I(ip1));
}
/*
@ -1366,18 +1384,12 @@ xfs_reflink_remap_prep(
struct xfs_inode *src = XFS_I(inode_in);
struct inode *inode_out = file_inode(file_out);
struct xfs_inode *dest = XFS_I(inode_out);
bool same_inode = (inode_in == inode_out);
int ret;
/* Lock both files against IO */
ret = xfs_iolock_two_inodes_and_break_layout(inode_in, inode_out);
ret = xfs_reflink_remap_lock(src, dest);
if (ret)
return ret;
if (same_inode)
xfs_ilock(src, XFS_MMAPLOCK_EXCL);
else
xfs_lock_two_inodes(src, XFS_MMAPLOCK_EXCL, dest,
XFS_MMAPLOCK_EXCL);
/* Check file eligibility and prepare for block sharing. */
ret = -EINVAL;
@ -1428,7 +1440,7 @@ xfs_reflink_remap_prep(
return 0;
out_unlock:
xfs_reflink_remap_unlock(file_in, file_out);
xfs_reflink_remap_unlock(src, dest);
return ret;
}

3
fs/xfs/xfs_reflink.h
View File

@ -56,7 +56,6 @@ extern int xfs_reflink_remap_blocks(struct xfs_inode *src, loff_t pos_in,
loff_t *remapped);
extern int xfs_reflink_update_dest(struct xfs_inode *dest, xfs_off_t newlen,
xfs_extlen_t cowextsize, unsigned int remap_flags);
extern void xfs_reflink_remap_unlock(struct file *file_in,
struct file *file_out);
extern void xfs_reflink_remap_unlock(struct xfs_inode *ip1, struct xfs_inode *ip2);
#endif /* __XFS_REFLINK_H */