@@ -3561,6 +3561,119 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon,
return rc;
}
+static int smb3_simple_fallocate_write_range(unsigned int xid,
+ struct cifs_tcon *tcon,
+ struct cifsFileInfo *cfile,
+ loff_t off, loff_t len,
+ char *buf)
+{
+ struct cifs_io_parms io_parms = {0};
+ int nbytes;
+ struct kvec iov[2];
+
+ io_parms.netfid = cfile->fid.netfid;
+ io_parms.pid = current->tgid;
+ io_parms.tcon = tcon;
+ io_parms.persistent_fid = cfile->fid.persistent_fid;
+ io_parms.volatile_fid = cfile->fid.volatile_fid;
+ io_parms.offset = off;
+ io_parms.length = len;
+
+ /* iov[0] is reserved for smb header */
+ iov[1].iov_base = buf;
+ iov[1].iov_len = io_parms.length;
+ return SMB2_write(xid, &io_parms, &nbytes, iov, 1);
+}
+
+static int smb3_simple_fallocate_range(unsigned int xid,
+ struct cifs_tcon *tcon,
+ struct cifsFileInfo *cfile,
+ loff_t off, loff_t len)
+{
+ struct file_allocated_range_buffer in_data, *out_data = NULL, *tmp_data;
+ u32 out_data_len;
+ char *buf = NULL;
+ loff_t l;
+ int rc;
+
+ in_data.file_offset = cpu_to_le64(off);
+ in_data.length = cpu_to_le64(len);
+ rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
+ cfile->fid.volatile_fid,
+ FSCTL_QUERY_ALLOCATED_RANGES, true,
+ (char *)&in_data, sizeof(in_data),
+ 1024 * sizeof(struct file_allocated_range_buffer),
+ (char **)&out_data, &out_data_len);
+ if (rc)
+ goto out;
+ /*
+ * It is already all allocated
+ */
+ if (out_data_len == 0)
+ goto out;
+
+ buf = kzalloc(1024 * 1024, GFP_KERNEL);
+ if (buf == NULL) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ tmp_data = out_data;
+ while (len) {
+ /*
+ * The rest of the region is unmapped so write it all.
+ */
+ if (out_data_len == 0) {
+ rc = smb3_simple_fallocate_write_range(xid, tcon,
+ cfile, off, len, buf);
+ goto out;
+ }
+
+ if (out_data_len < sizeof(struct file_allocated_range_buffer)) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (off < le64_to_cpu(tmp_data->file_offset)) {
+ /*
+ * We are at a hole. Write until the end of the region
+ * or until the next allocated data,
+ * whichever comes next.
+ */
+ l = le64_to_cpu(tmp_data->file_offset) - off;
+ if (len < l)
+ l = len;
+ rc = smb3_simple_fallocate_write_range(xid, tcon,
+ cfile, off, l, buf);
+ if (rc)
+ goto out;
+ off = off + l;
+ len = len - l;
+ if (len == 0)
+ goto out;
+ }
+ /*
+ * We are at a section of allocated data, just skip forward
+ * until the end of the data or the end of the region
+ * we are supposed to fallocate, whichever comes first.
+ */
+ l = le64_to_cpu(tmp_data->length);
+ if (len < l)
+ l = len;
+ off += l;
+ len -= l;
+
+ tmp_data = &tmp_data[1];
+ out_data_len -= sizeof(struct file_allocated_range_buffer);
+ }
+
+ out:
+ kfree(out_data);
+ kfree(buf);
+ return rc;
+}
+
+
static long smb3_simple_falloc(struct file *file, struct cifs_tcon *tcon,
loff_t off, loff_t len, bool keep_size)
{
@@ -3621,6 +3734,26 @@ static long smb3_simple_falloc(struct file *file, struct cifs_tcon *tcon,
}
if ((keep_size == true) || (i_size_read(inode) >= off + len)) {
+ /*
+ * At this point, we are trying to fallocate an internal
+ * regions of a sparse file. Since smb2 does not have a
+ * fallocate command we have two otions on how to emulate this.
+ * We can either turn the entire file to become non-sparse
+ * which we only do if the fallocate is for virtually
+ * the whole file, or we can overwrite the region with zeroes
+ * using SMB2_write, which could be prohibitevly expensive
+ * if len is large.
+ */
+ /*
+ * We are only trying to fallocate a small region so
+ * just write it with zero.
+ */
+ if (len <= 1024 * 1024) {
+ rc = smb3_simple_fallocate_range(xid, tcon, cfile,
+ off, len);
+ goto out;
+ }
+
/*
* Check if falloc starts within first few pages of file
* and ends within a few pages of the end of file to