cifs: don't bother with kmap on read_pages side

just do ITER_BVEC recvmsg

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
2016-01-09 19:54:50 -05:00
parent a6137305a8
commit 71335664c3
3 changed files with 56 additions and 71 deletions

View File

@@ -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;