From ce32c58c0afe1832c8d4ec4b1d789453bcfceb5a Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Thu, 14 Oct 2021 17:44:48 +0800 Subject: [PATCH] cifs: only write 64kb at a time when fallocating a small region of a file stable inclusion from stable-5.10.54 commit c26372b8a8c301d56204cddb9aedfa2c67adac17 bugzilla: 175586 https://gitee.com/openeuler/kernel/issues/I4DVDU Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c26372b8a8c301d56204cddb9aedfa2c67adac17 -------------------------------- [ Upstream commit 2485bd7557a7edb4520b4072af464f0a08c8efe0 ] We only allow sending single credit writes through the SMB2_write() synchronous api so split this into smaller chunks. Fixes: 966a3cb7c7db ("cifs: improve fallocate emulation") Signed-off-by: Ronnie Sahlberg Reported-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin Signed-off-by: Chen Jun Acked-by: Weilong Chen Signed-off-by: Chen Jun Signed-off-by: Zheng Zengkai --- fs/cifs/smb2ops.c | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index f6ceb79a995d..442bf422aa01 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3466,7 +3466,7 @@ static int smb3_simple_fallocate_write_range(unsigned int xid, char *buf) { struct cifs_io_parms io_parms = {0}; - int nbytes; + int rc, nbytes; struct kvec iov[2]; io_parms.netfid = cfile->fid.netfid; @@ -3474,13 +3474,25 @@ static int smb3_simple_fallocate_write_range(unsigned int xid, 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); + while (len) { + io_parms.offset = off; + io_parms.length = len; + if (io_parms.length > SMB2_MAX_BUFFER_SIZE) + io_parms.length = SMB2_MAX_BUFFER_SIZE; + /* iov[0] is reserved for smb header */ + iov[1].iov_base = buf; + iov[1].iov_len = io_parms.length; + rc = SMB2_write(xid, &io_parms, &nbytes, iov, 1); + if (rc) + break; + if (nbytes > len) + return -EINVAL; + buf += nbytes; + off += nbytes; + len -= nbytes; + } + return rc; } static int smb3_simple_fallocate_range(unsigned int xid, -- GitLab