From 8321fec436050b586cee448f2da0a6999e5172dd Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 19 Sep 2012 06:22:32 -0700 Subject: [PATCH] cifs: convert async read code to use pages array without kmapping Replace the "marshal_iov" function with a "read_into_pages" function. That function will copy the read data off the socket and into the pages array, kmapping and reading pages one at a time. Signed-off-by: Jeff Layton --- fs/cifs/cifsglob.h | 7 +++- fs/cifs/cifssmb.c | 27 +++++------- fs/cifs/file.c | 121 ++++++++++++++++++++++++++--------------------------- fs/cifs/smb2pdu.c | 6 ++- 4 files changed, 80 insertions(+), 81 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index b70863e..93e1620 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -978,8 +978,11 @@ struct cifs_readdata { pid_t pid; int result; struct work_struct work; - int (*marshal_iov) (struct cifs_readdata *rdata, - unsigned int remaining); + int (*read_into_pages)(struct TCP_Server_Info *server, + struct cifs_readdata *rdata, + unsigned int len); + unsigned int pagesz; + unsigned int tailsz; unsigned int nr_iov; struct kvec *iov; unsigned int nr_pages; diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index a110e07..5d7bd75 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -1496,6 +1496,7 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid) /* set up first iov for signature check */ rdata->iov[0].iov_base = buf; rdata->iov[0].iov_len = server->total_read; + rdata->nr_iov = 1; cFYI(1, "0: iov_base=%p iov_len=%zu", rdata->iov[0].iov_base, rdata->iov[0].iov_len); @@ -1507,23 +1508,11 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid) return cifs_readv_discard(server, mid); } - /* marshal up the page array */ - cifs_kmap_lock(); - len = rdata->marshal_iov(rdata, data_len); - cifs_kmap_unlock(); - data_len -= len; - - /* issue the read if we have any iovecs left to fill */ - if (rdata->nr_iov > 1) { - length = cifs_readv_from_socket(server, &rdata->iov[1], - rdata->nr_iov - 1, len); - if (length < 0) - return length; - server->total_read += length; - } else { - length = 0; - } + length = rdata->read_into_pages(server, rdata, data_len); + if (length < 0) + return length; + server->total_read += length; rdata->bytes = length; cFYI(1, "total_read=%u buflen=%u remaining=%u", server->total_read, @@ -1544,7 +1533,11 @@ cifs_readv_callback(struct mid_q_entry *mid) struct cifs_tcon *tcon = tlink_tcon(rdata->cfile->tlink); struct TCP_Server_Info *server = tcon->ses->server; struct smb_rqst rqst = { .rq_iov = rdata->iov, - .rq_nvec = rdata->nr_iov }; + .rq_nvec = rdata->nr_iov, + .rq_pages = rdata->pages, + .rq_npages = rdata->nr_pages, + .rq_pagesz = rdata->pagesz, + .rq_tailsz = rdata->tailsz }; cFYI(1, "%s: mid=%llu state=%d result=%d bytes=%u", __func__, mid->mid, mid->mid_state, rdata->result, rdata->bytes); diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 6eaf482..f3f1b10 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2566,63 +2566,57 @@ cifs_uncached_readv_complete(struct work_struct *work) { struct cifs_readdata *rdata = container_of(work, struct cifs_readdata, work); - unsigned int i; - - /* if the result is non-zero then the pages weren't kmapped */ - if (rdata->result == 0) { - for (i = 0; i < rdata->nr_pages; i++) - kunmap(rdata->pages[i]); - } complete(&rdata->done); kref_put(&rdata->refcount, cifs_uncached_readdata_release); } static int -cifs_uncached_read_marshal_iov(struct cifs_readdata *rdata, - unsigned int remaining) +cifs_uncached_read_into_pages(struct TCP_Server_Info *server, + struct cifs_readdata *rdata, unsigned int len) { - int len = 0; + int total_read = 0, result = 0; unsigned int i; unsigned int nr_pages = rdata->nr_pages; + struct kvec iov; - rdata->nr_iov = 1; + rdata->tailsz = PAGE_SIZE; for (i = 0; i < nr_pages; i++) { struct page *page = rdata->pages[i]; - if (remaining >= PAGE_SIZE) { + if (len >= PAGE_SIZE) { /* enough data to fill the page */ - rdata->iov[rdata->nr_iov].iov_base = kmap(page); - rdata->iov[rdata->nr_iov].iov_len = PAGE_SIZE; - cFYI(1, "%u: idx=%lu iov_base=%p iov_len=%zu", - rdata->nr_iov, page->index, - rdata->iov[rdata->nr_iov].iov_base, - rdata->iov[rdata->nr_iov].iov_len); - ++rdata->nr_iov; - len += PAGE_SIZE; - remaining -= PAGE_SIZE; - } else if (remaining > 0) { + iov.iov_base = kmap(page); + iov.iov_len = PAGE_SIZE; + cFYI(1, "%u: iov_base=%p iov_len=%zu", + i, iov.iov_base, iov.iov_len); + len -= PAGE_SIZE; + } else if (len > 0) { /* enough for partial page, fill and zero the rest */ - rdata->iov[rdata->nr_iov].iov_base = kmap(page); - rdata->iov[rdata->nr_iov].iov_len = remaining; - cFYI(1, "%u: idx=%lu iov_base=%p iov_len=%zu", - rdata->nr_iov, page->index, - rdata->iov[rdata->nr_iov].iov_base, - rdata->iov[rdata->nr_iov].iov_len); - memset(rdata->iov[rdata->nr_iov].iov_base + remaining, - '\0', PAGE_SIZE - remaining); - ++rdata->nr_iov; - len += remaining; - remaining = 0; + iov.iov_base = kmap(page); + iov.iov_len = len; + cFYI(1, "%u: iov_base=%p iov_len=%zu", + i, iov.iov_base, iov.iov_len); + memset(iov.iov_base + len, '\0', PAGE_SIZE - len); + rdata->tailsz = len; + len = 0; } else { /* 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); + if (result < 0) + break; + + total_read += result; } - return len; + return total_read > 0 ? total_read : result; } static ssize_t @@ -2685,7 +2679,8 @@ cifs_iovec_read(struct file *file, const struct iovec *iov, rdata->offset = offset; rdata->bytes = cur_len; rdata->pid = pid; - rdata->marshal_iov = cifs_uncached_read_marshal_iov; + rdata->pagesz = PAGE_SIZE; + rdata->read_into_pages = cifs_uncached_read_into_pages; rc = cifs_retry_async_readv(rdata); error: @@ -2935,7 +2930,6 @@ cifs_readv_complete(struct work_struct *work) lru_cache_add_file(page); if (rdata->result == 0) { - kunmap(page); flush_dcache_page(page); SetPageUptodate(page); } @@ -2952,47 +2946,42 @@ cifs_readv_complete(struct work_struct *work) } static int -cifs_readpages_marshal_iov(struct cifs_readdata *rdata, unsigned int remaining) +cifs_readpages_read_into_pages(struct TCP_Server_Info *server, + struct cifs_readdata *rdata, unsigned int len) { - int len = 0; + int total_read = 0, result = 0; unsigned int i; 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; eof_index = eof ? (eof - 1) >> PAGE_CACHE_SHIFT : 0; cFYI(1, "eof=%llu eof_index=%lu", eof, eof_index); - rdata->nr_iov = 1; + rdata->tailsz = PAGE_CACHE_SIZE; for (i = 0; i < nr_pages; i++) { struct page *page = rdata->pages[i]; - if (remaining >= PAGE_CACHE_SIZE) { + if (len >= PAGE_CACHE_SIZE) { /* enough data to fill the page */ - rdata->iov[rdata->nr_iov].iov_base = kmap(page); - rdata->iov[rdata->nr_iov].iov_len = PAGE_CACHE_SIZE; + iov.iov_base = kmap(page); + iov.iov_len = PAGE_CACHE_SIZE; cFYI(1, "%u: idx=%lu iov_base=%p iov_len=%zu", - rdata->nr_iov, page->index, - rdata->iov[rdata->nr_iov].iov_base, - rdata->iov[rdata->nr_iov].iov_len); - ++rdata->nr_iov; - len += PAGE_CACHE_SIZE; - remaining -= PAGE_CACHE_SIZE; - } else if (remaining > 0) { + 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 */ - rdata->iov[rdata->nr_iov].iov_base = kmap(page); - rdata->iov[rdata->nr_iov].iov_len = remaining; + iov.iov_base = kmap(page); + iov.iov_len = len; cFYI(1, "%u: idx=%lu iov_base=%p iov_len=%zu", - rdata->nr_iov, page->index, - rdata->iov[rdata->nr_iov].iov_base, - rdata->iov[rdata->nr_iov].iov_len); - memset(rdata->iov[rdata->nr_iov].iov_base + remaining, - '\0', PAGE_CACHE_SIZE - remaining); - ++rdata->nr_iov; - len += remaining; - remaining = 0; + i, page->index, iov.iov_base, iov.iov_len); + memset(iov.iov_base + len, + '\0', PAGE_CACHE_SIZE - len); + rdata->tailsz = len; + len = 0; } else if (page->index > eof_index) { /* * The VFS will not try to do readahead past the @@ -3010,6 +2999,7 @@ cifs_readpages_marshal_iov(struct cifs_readdata *rdata, unsigned int remaining) page_cache_release(page); rdata->pages[i] = NULL; rdata->nr_pages--; + continue; } else { /* no need to hold page hostage */ lru_cache_add_file(page); @@ -3017,10 +3007,18 @@ cifs_readpages_marshal_iov(struct cifs_readdata *rdata, unsigned int remaining) page_cache_release(page); rdata->pages[i] = NULL; rdata->nr_pages--; + continue; } + + result = cifs_readv_from_socket(server, &iov, 1, iov.iov_len); + kunmap(page); + if (result < 0) + break; + + total_read += result; } - return len; + return total_read > 0 ? total_read : result; } static int cifs_readpages(struct file *file, struct address_space *mapping, @@ -3144,7 +3142,8 @@ static int cifs_readpages(struct file *file, struct address_space *mapping, rdata->offset = offset; rdata->bytes = bytes; rdata->pid = pid; - rdata->marshal_iov = cifs_readpages_marshal_iov; + rdata->pagesz = PAGE_CACHE_SIZE; + rdata->read_into_pages = cifs_readpages_read_into_pages; list_for_each_entry_safe(page, tpage, &tmplist, lru) { list_del(&page->lru); diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 68023d2..e3efa47 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1300,7 +1300,11 @@ smb2_readv_callback(struct mid_q_entry *mid) struct smb2_hdr *buf = (struct smb2_hdr *)rdata->iov[0].iov_base; unsigned int credits_received = 1; struct smb_rqst rqst = { .rq_iov = rdata->iov, - .rq_nvec = rdata->nr_iov }; + .rq_nvec = 1, + .rq_pages = rdata->pages, + .rq_npages = rdata->nr_pages, + .rq_pagesz = rdata->pagesz, + .rq_tailsz = rdata->tailsz }; cFYI(1, "%s: mid=%llu state=%d result=%d bytes=%u", __func__, mid->mid, mid->mid_state, rdata->result, rdata->bytes); -- 2.7.4