dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

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 <jlayton@redhat.com>
This commit is contained in:
Jeff Layton 2012-09-19 06:22:32 -07:00 committed by Steve French
parent c5fab6f4f0
commit 8321fec436
4 changed files with 80 additions and 81 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
fs/cifs/cifsglob.h
View File

@ -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;

27
fs/cifs/cifssmb.c
View File

@ -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);

121
fs/cifs/file.c
View File

@ -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);

6
fs/cifs/smb2pdu.c
View File

@ -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);