1 files changed, 90 insertions, 0 deletions

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index a4273ddb9922..dfcb815275f1 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -19,6 +19,9 @@
 #include <linux/delay.h>
 #include "ext4_jbd2.h"
 #include "ext4.h"
+#include <linux/fsmap.h>
+#include "fsmap.h"
+#include <trace/events/ext4.h>
 
 /**
  * Swap memory between @a and @b for @len bytes.
@@ -489,6 +492,90 @@ int ext4_shutdown(struct super_block *sb, unsigned long arg)
         return 0;
 }
 
+struct getfsmap_info {
+        struct super_block      *gi_sb;
+        struct fsmap_head __user *gi_data;
+        unsigned int            gi_idx;
+        __u32                   gi_last_flags;
+};
+
+static int ext4_getfsmap_format(struct ext4_fsmap *xfm, void *priv)
+{
+        struct getfsmap_info *info = priv;
+        struct fsmap fm;
+
+        trace_ext4_getfsmap_mapping(info->gi_sb, xfm);
+
+        info->gi_last_flags = xfm->fmr_flags;
+        ext4_fsmap_from_internal(info->gi_sb, &fm, xfm);
+        if (copy_to_user(&info->gi_data->fmh_recs[info->gi_idx++], &fm,
+                        sizeof(struct fsmap)))
+                return -EFAULT;
+
+        return 0;
+}
+
+static int ext4_ioc_getfsmap(struct super_block *sb,
+                             struct fsmap_head __user *arg)
+{
+        struct getfsmap_info info = {0};
+        struct ext4_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;
+        /*
+         * ext4 doesn't report file extents at all, so the only valid
+         * file offsets are the magic ones (all zeroes or all ones).
+         */
+        if (head.fmh_keys[0].fmr_offset ||
+            (head.fmh_keys[1].fmr_offset != 0 &&
+             head.fmh_keys[1].fmr_offset != -1ULL))
+                return -EINVAL;
+
+        xhead.fmh_iflags = head.fmh_iflags;
+        xhead.fmh_count = head.fmh_count;
+        ext4_fsmap_to_internal(sb, &xhead.fmh_keys[0], &head.fmh_keys[0]);
+        ext4_fsmap_to_internal(sb, &xhead.fmh_keys[1], &head.fmh_keys[1]);
+
+        trace_ext4_getfsmap_low_key(sb, &xhead.fmh_keys[0]);
+        trace_ext4_getfsmap_high_key(sb, &xhead.fmh_keys[1]);
+
+        info.gi_sb = sb;
+        info.gi_data = arg;
+        error = ext4_getfsmap(sb, &xhead, ext4_getfsmap_format, &info);
+        if (error == EXT4_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 && info.gi_idx) {
+                info.gi_last_flags |= FMR_OF_LAST;
+                if (copy_to_user(&info.gi_data->fmh_recs[info.gi_idx - 1].fmr_flags,
+                                 &info.gi_last_flags,
+                                 sizeof(info.gi_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;
+}
+
 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
         struct inode *inode = file_inode(filp);
@@ -499,6 +586,8 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
         ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
 
         switch (cmd) {
+        case FS_IOC_GETFSMAP:
+                return ext4_ioc_getfsmap(sb, (void __user *)arg);
         case EXT4_IOC_GETFLAGS:
                 ext4_get_inode_flags(ei);
                 flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
@@ -1009,6 +1098,7 @@ long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
         case EXT4_IOC_GET_ENCRYPTION_PWSALT:
         case EXT4_IOC_GET_ENCRYPTION_POLICY:
         case EXT4_IOC_SHUTDOWN:
+        case FS_IOC_GETFSMAP:
                 break;
         default:
                 return -ENOIOCTLCMD;