These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / fs / hpfs / alloc.c

diff --git a/kernel/fs/hpfs/alloc.c b/kernel/fs/hpfs/alloc.c
index f005046..d6a4b55 100644 (file)
--- a/kernel/fs/hpfs/alloc.c
+++ b/kernel/fs/hpfs/alloc.c
@@ -484,3 +484,98 @@ struct anode *hpfs_alloc_anode(struct super_block *s, secno near, anode_secno *a
        a->btree.first_free = cpu_to_le16(8);
        return a;
 }
+
+static unsigned find_run(__le32 *bmp, unsigned *idx)
+{
+       unsigned len;
+       while (tstbits(bmp, *idx, 1)) {
+               (*idx)++;
+               if (unlikely(*idx >= 0x4000))
+                       return 0;
+       }
+       len = 1;
+       while (!tstbits(bmp, *idx + len, 1))
+               len++;
+       return len;
+}
+
+static int do_trim(struct super_block *s, secno start, unsigned len, secno limit_start, secno limit_end, unsigned minlen, unsigned *result)
+{
+       int err;
+       secno end;
+       if (fatal_signal_pending(current))
+               return -EINTR;
+       end = start + len;
+       if (start < limit_start)
+               start = limit_start;
+       if (end > limit_end)
+               end = limit_end;
+       if (start >= end)
+               return 0;
+       if (end - start < minlen)
+               return 0;
+       err = sb_issue_discard(s, start, end - start, GFP_NOFS, 0);
+       if (err)
+               return err;
+       *result += end - start;
+       return 0;
+}
+
+int hpfs_trim_fs(struct super_block *s, u64 start, u64 end, u64 minlen, unsigned *result)
+{
+       int err = 0;
+       struct hpfs_sb_info *sbi = hpfs_sb(s);
+       unsigned idx, len, start_bmp, end_bmp;
+       __le32 *bmp;
+       struct quad_buffer_head qbh;
+
+       *result = 0;
+       if (!end || end > sbi->sb_fs_size)
+               end = sbi->sb_fs_size;
+       if (start >= sbi->sb_fs_size)
+               return 0;
+       if (minlen > 0x4000)
+               return 0;
+       if (start < sbi->sb_dirband_start + sbi->sb_dirband_size && end > sbi->sb_dirband_start) {
+               hpfs_lock(s);
+               if (s->s_flags & MS_RDONLY) {
+                       err = -EROFS;
+                       goto unlock_1;
+               }
+               if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
+                       err = -EIO;
+                       goto unlock_1;
+               }
+               idx = 0;
+               while ((len = find_run(bmp, &idx)) && !err) {
+                       err = do_trim(s, sbi->sb_dirband_start + idx * 4, len * 4, start, end, minlen, result);
+                       idx += len;
+               }
+               hpfs_brelse4(&qbh);
+unlock_1:
+               hpfs_unlock(s);
+       }
+       start_bmp = start >> 14;
+       end_bmp = (end + 0x3fff) >> 14;
+       while (start_bmp < end_bmp && !err) {
+               hpfs_lock(s);
+               if (s->s_flags & MS_RDONLY) {
+                       err = -EROFS;
+                       goto unlock_2;
+               }
+               if (!(bmp = hpfs_map_bitmap(s, start_bmp, &qbh, "trim"))) {
+                       err = -EIO;
+                       goto unlock_2;
+               }
+               idx = 0;
+               while ((len = find_run(bmp, &idx)) && !err) {
+                       err = do_trim(s, (start_bmp << 14) + idx, len, start, end, minlen, result);
+                       idx += len;
+               }
+               hpfs_brelse4(&qbh);
+unlock_2:
+               hpfs_unlock(s);
+               start_bmp++;
+       }
+       return err;
+}