xfs: implement the GETFSMAP ioctl
Introduce a new ioctl that uses the reverse mapping btree to return
information about the physical layout of the filesystem.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 6d30b06..fee6b4a 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -41,6 +41,9 @@
#include "xfs_trans.h"
#include "xfs_pnfs.h"
#include "xfs_acl.h"
+#include "xfs_btree.h"
+#include <linux/fsmap.h>
+#include "xfs_fsmap.h"
#include <linux/capability.h>
#include <linux/cred.h>
@@ -1609,6 +1612,84 @@ xfs_ioc_getbmapx(
return 0;
}
+struct getfsmap_info {
+ struct xfs_mount *mp;
+ struct fsmap __user *data;
+ __u32 last_flags;
+};
+
+STATIC int
+xfs_getfsmap_format(struct xfs_fsmap *xfm, void *priv)
+{
+ struct getfsmap_info *info = priv;
+ struct fsmap fm;
+
+ trace_xfs_getfsmap_mapping(info->mp, xfm);
+
+ info->last_flags = xfm->fmr_flags;
+ xfs_fsmap_from_internal(&fm, xfm);
+ if (copy_to_user(info->data, &fm, sizeof(struct fsmap)))
+ return -EFAULT;
+
+ info->data++;
+ return 0;
+}
+
+STATIC int
+xfs_ioc_getfsmap(
+ struct xfs_inode *ip,
+ void __user *arg)
+{
+ struct getfsmap_info info = {0};
+ struct xfs_fsmap_head xhead = {0};
+ struct fsmap_head head;
+ bool aborted = false;
+ int error;
+
+ if (copy_from_user(&head, arg, sizeof(struct fsmap_head)))
+ return -EFAULT;
+ if (memchr_inv(head.fmh_reserved, 0, sizeof(head.fmh_reserved)) ||
+ memchr_inv(head.fmh_keys[0].fmr_reserved, 0,
+ sizeof(head.fmh_keys[0].fmr_reserved)) ||
+ memchr_inv(head.fmh_keys[1].fmr_reserved, 0,
+ sizeof(head.fmh_keys[1].fmr_reserved)))
+ return -EINVAL;
+
+ xhead.fmh_iflags = head.fmh_iflags;
+ xhead.fmh_count = head.fmh_count;
+ xfs_fsmap_to_internal(&xhead.fmh_keys[0], &head.fmh_keys[0]);
+ xfs_fsmap_to_internal(&xhead.fmh_keys[1], &head.fmh_keys[1]);
+
+ trace_xfs_getfsmap_low_key(ip->i_mount, &xhead.fmh_keys[0]);
+ trace_xfs_getfsmap_high_key(ip->i_mount, &xhead.fmh_keys[1]);
+
+ info.mp = ip->i_mount;
+ info.data = ((__force struct fsmap_head *)arg)->fmh_recs;
+ error = xfs_getfsmap(ip->i_mount, &xhead, xfs_getfsmap_format, &info);
+ if (error == XFS_BTREE_QUERY_RANGE_ABORT) {
+ error = 0;
+ aborted = true;
+ } else if (error)
+ return error;
+
+ /* If we didn't abort, set the "last" flag in the last fmx */
+ if (!aborted && xhead.fmh_entries) {
+ info.data--;
+ info.last_flags |= FMR_OF_LAST;
+ if (copy_to_user(&info.data->fmr_flags, &info.last_flags,
+ sizeof(info.last_flags)))
+ return -EFAULT;
+ }
+
+ /* copy back header */
+ head.fmh_entries = xhead.fmh_entries;
+ head.fmh_oflags = xhead.fmh_oflags;
+ if (copy_to_user(arg, &head, sizeof(struct fsmap_head)))
+ return -EFAULT;
+
+ return 0;
+}
+
int
xfs_ioc_swapext(
xfs_swapext_t *sxp)
@@ -1789,6 +1870,9 @@ xfs_file_ioctl(
case XFS_IOC_GETBMAPX:
return xfs_ioc_getbmapx(ip, arg);
+ case FS_IOC_GETFSMAP:
+ return xfs_ioc_getfsmap(ip, arg);
+
case XFS_IOC_FD_TO_HANDLE:
case XFS_IOC_PATH_TO_HANDLE:
case XFS_IOC_PATH_TO_FSHANDLE: {