Commit 8321fec4 authored by Jeff Layton's avatar Jeff Layton Committed by Steve French
Browse files

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: default avatarJeff Layton <jlayton@redhat.com>
parent c5fab6f4

fs/cifs/cifsglob.h

+5 −2
Original line number Diff line number Diff line
@@ -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;

fs/cifs/cifssmb.c

+10 −17
Original line number Diff line number Diff line
@@ -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);

	length = rdata->read_into_pages(server, rdata, data_len);

	if (length < 0)

		return length;

		server->total_read += length;

	} else {

		length = 0;

	}



	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);

fs/cifs/file.c

+60 −61
Original line number Diff line number Diff line
@@ -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);

fs/cifs/smb2pdu.c

+5 −1
Original line number Diff line number Diff line
@@ -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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE