From 30175628bf7f521e9ee31ac98fa6d6fe7441a556 Mon Sep 17 00:00:00 2001 From: Steve French Date: Sun, 17 Aug 2014 18:16:40 -0500 Subject: [SMB3] Enable fallocate -z support for SMB3 mounts fallocate -z (FALLOC_FL_ZERO_RANGE) can map to SMB3 FSCTL_SET_ZERO_DATA SMB3 FSCTL but FALLOC_FL_ZERO_RANGE when called without the FALLOC_FL_KEEPSIZE flag set could want the file size changed so we can not support that subcase unless the file is cached (and thus we know the file size). Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky --- fs/cifs/smb2ops.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) (limited to 'fs/cifs') diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 101670c2c374..5a48aa290dfe 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -1015,6 +1015,56 @@ smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon, return rc; } +static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon, + loff_t offset, loff_t len, bool keep_size) +{ + struct inode *inode; + struct cifsInodeInfo *cifsi; + struct cifsFileInfo *cfile = file->private_data; + struct file_zero_data_information fsctl_buf; + long rc; + unsigned int xid; + + xid = get_xid(); + + inode = cfile->dentry->d_inode; + cifsi = CIFS_I(inode); + + /* if file not oplocked can't be sure whether asking to extend size */ + if (!CIFS_CACHE_READ(cifsi)) + if (keep_size == false) + return -EOPNOTSUPP; + + /* + * Must check if file sparse since fallocate -z (zero range) assumes + * non-sparse allocation + */ + if (!(cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE)) + return -EOPNOTSUPP; + + /* + * need to make sure we are not asked to extend the file since the SMB3 + * fsctl does not change the file size. In the future we could change + * this to zero the first part of the range then set the file size + * which for a non sparse file would zero the newly extended range + */ + if (keep_size == false) + if (i_size_read(inode) < offset + len) + return -EOPNOTSUPP; + + cifs_dbg(FYI, "offset %lld len %lld", offset, len); + + fsctl_buf.FileOffset = cpu_to_le64(offset); + fsctl_buf.BeyondFinalZero = cpu_to_le64(offset + len); + + rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid, + cfile->fid.volatile_fid, FSCTL_SET_ZERO_DATA, + true /* is_fctl */, (char *)&fsctl_buf, + sizeof(struct file_zero_data_information), NULL, NULL); + free_xid(xid); + return rc; +} + static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon, loff_t offset, loff_t len) { @@ -1055,6 +1105,11 @@ static long smb3_fallocate(struct file *file, struct cifs_tcon *tcon, int mode, /* KEEP_SIZE already checked for by do_fallocate */ if (mode & FALLOC_FL_PUNCH_HOLE) return smb3_punch_hole(file, tcon, off, len); + else if (mode & FALLOC_FL_ZERO_RANGE) { + if (mode & FALLOC_FL_KEEP_SIZE) + return smb3_zero_range(file, tcon, off, len, true); + return smb3_zero_range(file, tcon, off, len, false); + } return -EOPNOTSUPP; } -- cgit v1.2.3