From 09aab880f7c5ac31e9db18a63353b980bcb52261 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 13 Nov 2015 03:00:17 -0500 Subject: cifs: no need to wank with copying and advancing iovec on recvmsg side either Signed-off-by: Al Viro --- fs/cifs/connect.c | 72 ++++--------------------------------------------------- 1 file changed, 5 insertions(+), 67 deletions(-) (limited to 'fs/cifs/connect.c') diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index a763cd3d9e7c..eb426658566d 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); -- cgit v1.2.3 From 71335664c38f03de10d7cf1d82705fe55a130b33 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 9 Jan 2016 19:54:50 -0500 Subject: cifs: don't bother with kmap on read_pages side just do ITER_BVEC recvmsg Signed-off-by: Al Viro --- fs/cifs/cifsproto.h | 7 +++--- fs/cifs/connect.c | 65 ++++++++++++++++++++++++++++------------------------- fs/cifs/file.c | 53 ++++++++++++++----------------------------- 3 files changed, 55 insertions(+), 70 deletions(-) (limited to 'fs/cifs/connect.c') diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index 7d5f53a01922..0f9a6bc4ba43 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -179,10 +179,9 @@ extern int set_cifs_acl(struct cifs_ntsd *, __u32, struct inode *, extern void dequeue_mid(struct mid_q_entry *mid, bool malformed); extern int cifs_read_from_socket(struct TCP_Server_Info *server, char *buf, - unsigned int to_read); -extern int cifs_readv_from_socket(struct TCP_Server_Info *server, - struct kvec *iov_orig, unsigned int nr_segs, - unsigned int to_read); + unsigned int to_read); +extern int cifs_read_page_from_socket(struct TCP_Server_Info *server, + struct page *page, unsigned int to_read); extern void cifs_setup_cifs_sb(struct smb_vol *pvolume_info, struct cifs_sb_info *cifs_sb); extern int cifs_match_super(struct super_block *, void *); diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index eb426658566d..e33c5e0ecfd0 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -501,39 +501,34 @@ server_unresponsive(struct TCP_Server_Info *server) return false; } -int -cifs_readv_from_socket(struct TCP_Server_Info *server, struct kvec *iov_orig, - unsigned int nr_segs, unsigned int to_read) +static int +cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg) { int length = 0; int total_read; - struct msghdr smb_msg; - 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); + smb_msg->msg_control = NULL; + smb_msg->msg_controllen = 0; - for (total_read = 0; msg_data_left(&smb_msg); total_read += length) { + for (total_read = 0; msg_data_left(smb_msg); total_read += length) { try_to_freeze(); - if (server_unresponsive(server)) { - total_read = -ECONNABORTED; - break; - } + if (server_unresponsive(server)) + return -ECONNABORTED; - length = sock_recvmsg(server->ssocket, &smb_msg, 0); + length = sock_recvmsg(server->ssocket, smb_msg, 0); - if (server->tcpStatus == CifsExiting) { - total_read = -ESHUTDOWN; - break; - } else if (server->tcpStatus == CifsNeedReconnect) { + if (server->tcpStatus == CifsExiting) + return -ESHUTDOWN; + + if (server->tcpStatus == CifsNeedReconnect) { cifs_reconnect(server); - total_read = -ECONNABORTED; - break; - } else if (length == -ERESTARTSYS || - length == -EAGAIN || - length == -EINTR) { + return -ECONNABORTED; + } + + if (length == -ERESTARTSYS || + length == -EAGAIN || + length == -EINTR) { /* * Minimum sleep to prevent looping, allowing socket * to clear and app threads to set tcpStatus @@ -542,11 +537,12 @@ cifs_readv_from_socket(struct TCP_Server_Info *server, struct kvec *iov_orig, usleep_range(1000, 2000); length = 0; continue; - } else if (length <= 0) { + } + + if (length <= 0) { cifs_dbg(FYI, "Received no data or error: %d\n", length); cifs_reconnect(server); - total_read = -ECONNABORTED; - break; + return -ECONNABORTED; } } return total_read; @@ -556,12 +552,21 @@ int cifs_read_from_socket(struct TCP_Server_Info *server, char *buf, unsigned int to_read) { - struct kvec iov; + struct msghdr smb_msg; + struct kvec iov = {.iov_base = buf, .iov_len = to_read}; + iov_iter_kvec(&smb_msg.msg_iter, READ | ITER_KVEC, &iov, 1, to_read); - iov.iov_base = buf; - iov.iov_len = to_read; + return cifs_readv_from_socket(server, &smb_msg); +} - return cifs_readv_from_socket(server, &iov, 1, to_read); +int +cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page, + unsigned int to_read) +{ + struct msghdr smb_msg; + struct bio_vec bv = {.bv_page = page, .bv_len = to_read}; + iov_iter_bvec(&smb_msg.msg_iter, READ | ITER_BVEC, &bv, 1, to_read); + return cifs_readv_from_socket(server, &smb_msg); } static bool diff --git a/fs/cifs/file.c b/fs/cifs/file.c index ff882aeaccc6..0f718679186e 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2855,39 +2855,31 @@ cifs_uncached_read_into_pages(struct TCP_Server_Info *server, int result = 0; unsigned int i; unsigned int nr_pages = rdata->nr_pages; - struct kvec iov; rdata->got_bytes = 0; rdata->tailsz = PAGE_SIZE; for (i = 0; i < nr_pages; i++) { struct page *page = rdata->pages[i]; + size_t n; - if (len >= PAGE_SIZE) { - /* enough data to fill the page */ - iov.iov_base = kmap(page); - iov.iov_len = PAGE_SIZE; - cifs_dbg(FYI, "%u: iov_base=%p iov_len=%zu\n", - i, iov.iov_base, iov.iov_len); - len -= PAGE_SIZE; - } else if (len > 0) { - /* enough for partial page, fill and zero the rest */ - iov.iov_base = kmap(page); - iov.iov_len = len; - cifs_dbg(FYI, "%u: iov_base=%p iov_len=%zu\n", - i, iov.iov_base, iov.iov_len); - memset(iov.iov_base + len, '\0', PAGE_SIZE - len); - rdata->tailsz = len; - len = 0; - } else { + if (len <= 0) { /* no need to hold page hostage */ rdata->pages[i] = NULL; rdata->nr_pages--; put_page(page); continue; } - - result = cifs_readv_from_socket(server, &iov, 1, iov.iov_len); - kunmap(page); + n = len; + if (len >= PAGE_SIZE) { + /* enough data to fill the page */ + n = PAGE_SIZE; + len -= n; + } else { + zero_user(page, len, PAGE_SIZE - len); + rdata->tailsz = len; + len = 0; + } + result = cifs_read_page_from_socket(server, page, n); if (result < 0) break; @@ -3303,7 +3295,6 @@ cifs_readpages_read_into_pages(struct TCP_Server_Info *server, u64 eof; pgoff_t eof_index; unsigned int nr_pages = rdata->nr_pages; - struct kvec iov; /* determine the eof that the server (probably) has */ eof = CIFS_I(rdata->mapping->host)->server_eof; @@ -3314,23 +3305,14 @@ cifs_readpages_read_into_pages(struct TCP_Server_Info *server, rdata->tailsz = PAGE_CACHE_SIZE; for (i = 0; i < nr_pages; i++) { struct page *page = rdata->pages[i]; + size_t n = PAGE_CACHE_SIZE; if (len >= PAGE_CACHE_SIZE) { - /* enough data to fill the page */ - iov.iov_base = kmap(page); - iov.iov_len = PAGE_CACHE_SIZE; - cifs_dbg(FYI, "%u: idx=%lu iov_base=%p iov_len=%zu\n", - i, page->index, iov.iov_base, iov.iov_len); len -= PAGE_CACHE_SIZE; } else if (len > 0) { /* enough for partial page, fill and zero the rest */ - iov.iov_base = kmap(page); - iov.iov_len = len; - cifs_dbg(FYI, "%u: idx=%lu iov_base=%p iov_len=%zu\n", - i, page->index, iov.iov_base, iov.iov_len); - memset(iov.iov_base + len, - '\0', PAGE_CACHE_SIZE - len); - rdata->tailsz = len; + zero_user(page, len, PAGE_CACHE_SIZE - len); + n = rdata->tailsz = len; len = 0; } else if (page->index > eof_index) { /* @@ -3360,8 +3342,7 @@ cifs_readpages_read_into_pages(struct TCP_Server_Info *server, continue; } - result = cifs_readv_from_socket(server, &iov, 1, iov.iov_len); - kunmap(page); + result = cifs_read_page_from_socket(server, page, n); if (result < 0) break; -- cgit v1.2.3