Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933670AbcDSRz0 (ORCPT ); Tue, 19 Apr 2016 13:55:26 -0400 Received: from mail-pf0-f176.google.com ([209.85.192.176]:35421 "EHLO mail-pf0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933617AbcDSRzV (ORCPT ); Tue, 19 Apr 2016 13:55:21 -0400 Message-ID: <1461088511.15135.11.camel@poochiereds.net> Subject: Re: [PATCH 4/6] cifs: no need to wank with copying and advancing iovec on recvmsg side either From: Jeff Layton To: Al Viro , linux-cifs@vger.kernel.org Cc: linux-kernel@vger.kernel.org Date: Tue, 19 Apr 2016 13:55:11 -0400 In-Reply-To: <20160409205210.GJ25498@ZenIV.linux.org.uk> References: <20160409204301.GF25498@ZenIV.linux.org.uk> <20160409205210.GJ25498@ZenIV.linux.org.uk> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.18.5.2 (3.18.5.2-1.fc23) Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4613 Lines: 139 On Sat, 2016-04-09 at 21:52 +0100, Al Viro wrote: > Signed-off-by: Al Viro > --- >  fs/cifs/cifsglob.h |  2 -- >  fs/cifs/connect.c  | 72 ++++-------------------------------------------------- >  2 files changed, 5 insertions(+), 69 deletions(-) > > diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h > index d21da9f..df03c5e 100644 > --- a/fs/cifs/cifsglob.h > +++ b/fs/cifs/cifsglob.h > @@ -615,8 +615,6 @@ struct TCP_Server_Info { >   bool sec_mskerberos; /* supports legacy MS Kerberos */ >   bool large_buf; /* is current buffer large? */ >   struct delayed_work echo; /* echo ping workqueue job */ > - struct kvec *iov; /* reusable kvec array for receives */ > - unsigned int nr_iov; /* number of kvecs in array */ >   char *smallbuf; /* pointer to current "small" buffer */ >   char *bigbuf; /* pointer to current "big" buffer */ >   unsigned int total_read; /* total amount of data read in this pass */ > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c > index a763cd3..eb42665 100644 > --- a/fs/cifs/connect.c > +++ b/fs/cifs/connect.c > @@ -501,77 +501,20 @@ server_unresponsive(struct TCP_Server_Info *server) >   return false; >  } >   > -/* > - * kvec_array_init - clone a kvec array, and advance into it > - * @new: pointer to memory for cloned array > - * @iov: pointer to original array > - * @nr_segs: number of members in original array > - * @bytes: number of bytes to advance into the cloned array > - * > - * This function will copy the array provided in iov to a section of memory > - * and advance the specified number of bytes into the new array. It returns > - * the number of segments in the new array. "new" must be at least as big as > - * the original iov array. > - */ > -static unsigned int > -kvec_array_init(struct kvec *new, struct kvec *iov, unsigned int nr_segs, > - size_t bytes) > -{ > - size_t base = 0; > - > - while (bytes || !iov->iov_len) { > - int copy = min(bytes, iov->iov_len); > - > - bytes -= copy; > - base += copy; > - if (iov->iov_len == base) { > - iov++; > - nr_segs--; > - base = 0; > - } > - } > - memcpy(new, iov, sizeof(*iov) * nr_segs); > - new->iov_base += base; > - new->iov_len -= base; > - return nr_segs; > -} > - > -static struct kvec * > -get_server_iovec(struct TCP_Server_Info *server, unsigned int nr_segs) > -{ > - struct kvec *new_iov; > - > - if (server->iov && nr_segs <= server->nr_iov) > - return server->iov; > - > - /* not big enough -- allocate a new one and release the old */ > - new_iov = kmalloc(sizeof(*new_iov) * nr_segs, GFP_NOFS); > - if (new_iov) { > - kfree(server->iov); > - server->iov = new_iov; > - server->nr_iov = nr_segs; > - } > - return new_iov; > -} > - >  int >  cifs_readv_from_socket(struct TCP_Server_Info *server, struct kvec *iov_orig, >          unsigned int nr_segs, unsigned int to_read) >  { >   int length = 0; >   int total_read; > - unsigned int segs; >   struct msghdr smb_msg; > - struct kvec *iov; > - > - iov = get_server_iovec(server, nr_segs); > - if (!iov) > - return -ENOMEM; >   >   smb_msg.msg_control = NULL; >   smb_msg.msg_controllen = 0; > + iov_iter_kvec(&smb_msg.msg_iter, READ | ITER_KVEC, > +       iov_orig, nr_segs, to_read); >   > - for (total_read = 0; to_read; total_read += length, to_read -= length) { > + for (total_read = 0; msg_data_left(&smb_msg); total_read += length) { >   try_to_freeze(); >   >   if (server_unresponsive(server)) { > @@ -579,10 +522,7 @@ cifs_readv_from_socket(struct TCP_Server_Info *server, struct kvec *iov_orig, >   break; >   } >   > - segs = kvec_array_init(iov, iov_orig, nr_segs, total_read); > - > - length = kernel_recvmsg(server->ssocket, &smb_msg, > - iov, segs, to_read, 0); > + length = sock_recvmsg(server->ssocket, &smb_msg, 0); >   >   if (server->tcpStatus == CifsExiting) { >   total_read = -ESHUTDOWN; > @@ -603,8 +543,7 @@ cifs_readv_from_socket(struct TCP_Server_Info *server, struct kvec *iov_orig, >   length = 0; >   continue; >   } else if (length <= 0) { > - cifs_dbg(FYI, "Received no data or error: expecting %d\n" > -  "got %d", to_read, length); > + cifs_dbg(FYI, "Received no data or error: %d\n", length); >   cifs_reconnect(server); >   total_read = -ECONNABORTED; >   break; > @@ -783,7 +722,6 @@ static void clean_demultiplex_info(struct TCP_Server_Info *server) >   } >   >   kfree(server->hostname); > - kfree(server->iov); >   kfree(server); >   >   length = atomic_dec_return(&tcpSesAllocCount); Good riddance. Reviewed-by: Jeff Layton