Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 56e4ebf8 authored by Bryan Schumaker's avatar Bryan Schumaker Committed by Trond Myklebust
Browse files

NFS: readdir with vmapped pages 



We can use vmapped pages to read more information from the network at once.
This will reduce the number of calls needed to complete a readdir.

Signed-off-by: default avatarBryan Schumaker <bjschuma@netapp.com>
[trondmy: Added #include for linux/vmalloc.h> in fs/nfs/dir.c]
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent afa8ccc9

fs/nfs/client.c

+2 −2
Original line number Diff line number Diff line
@@ -903,8 +903,8 @@ static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo * 
	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);



	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);

	if (server->dtsize > PAGE_CACHE_SIZE)

		server->dtsize = PAGE_CACHE_SIZE;

	if (server->dtsize > PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES)

		server->dtsize = PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES;

	if (server->dtsize > server->rsize)

		server->dtsize = server->rsize;

fs/nfs/dir.c

+54 −12
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ 
#include <linux/namei.h>

#include <linux/mount.h>

#include <linux/sched.h>

#include <linux/vmalloc.h>



#include "delegation.h"

#include "iostat.h"
@@ -327,7 +328,7 @@ int nfs_readdir_search_array(nfs_readdir_descriptor_t *desc) 


/* Fill a page with xdr information before transferring to the cache page */

static

int nfs_readdir_xdr_filler(struct page *xdr_page, nfs_readdir_descriptor_t *desc,

int nfs_readdir_xdr_filler(struct page **pages, nfs_readdir_descriptor_t *desc,

			struct nfs_entry *entry, struct file *file, struct inode *inode)

{

	struct rpc_cred	*cred = nfs_file_cred(file);
@@ -337,7 +338,7 @@ int nfs_readdir_xdr_filler(struct page *xdr_page, nfs_readdir_descriptor_t *desc 
 again:

	timestamp = jiffies;

	gencount = nfs_inc_attr_generation_counter();

	error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, entry->cookie, xdr_page,

	error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, entry->cookie, pages,

					  NFS_SERVER(inode)->dtsize, desc->plus);

	if (error < 0) {

		/* We requested READDIRPLUS, but the server doesn't grok it */
@@ -436,11 +437,11 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry) 
/* Perform conversion from xdr to cache array */

static

void nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *entry,

				struct page *xdr_page, struct page *page, unsigned int buflen)

				void *xdr_page, struct page *page, unsigned int buflen)

{

	struct xdr_stream stream;

	struct xdr_buf buf;

	__be32 *ptr = kmap(xdr_page);

	__be32 *ptr = xdr_page;



	buf.head->iov_base = xdr_page;

	buf.head->iov_len = buflen;
@@ -458,18 +459,59 @@ void nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *e 
		if (desc->plus == 1)

			nfs_prime_dcache(desc->file->f_path.dentry, entry);

	}

	kunmap(xdr_page);

}



static

void nfs_readdir_free_pagearray(struct page **pages, unsigned int npages)

{

	unsigned int i;

	for (i = 0; i < npages; i++)

		put_page(pages[i]);

}



static

void nfs_readdir_free_large_page(void *ptr, struct page **pages,

		unsigned int npages)

{

	vm_unmap_ram(ptr, npages);

	nfs_readdir_free_pagearray(pages, npages);

}



/*

 * nfs_readdir_large_page will allocate pages that must be freed with a call

 * to nfs_readdir_free_large_page

 */

static

void *nfs_readdir_large_page(struct page **pages, unsigned int npages)

{

	void *ptr;

	unsigned int i;



	for (i = 0; i < npages; i++) {

		struct page *page = alloc_page(GFP_KERNEL);

		if (page == NULL)

			goto out_freepages;

		pages[i] = page;

	}



	ptr = vm_map_ram(pages, NFS_MAX_READDIR_PAGES, 0, PAGE_KERNEL);

	if (!IS_ERR_OR_NULL(ptr))

		return ptr;

out_freepages:

	nfs_readdir_free_pagearray(pages, i);

	return NULL;

}



static

int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, struct inode *inode)

{

	struct page *xdr_page;

	struct page *pages[NFS_MAX_READDIR_PAGES];

	void *pages_ptr = NULL;

	struct nfs_entry entry;

	struct file	*file = desc->file;

	struct nfs_cache_array *array;

	int status = 0;

	unsigned int array_size = 1;

	unsigned int array_size = ARRAY_SIZE(pages);



	entry.prev_cookie = 0;

	entry.cookie = *desc->dir_cookie;
@@ -483,18 +525,18 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, 
	memset(array, 0, sizeof(struct nfs_cache_array));

	array->eof_index = -1;



	xdr_page = alloc_page(GFP_KERNEL);

	if (!xdr_page)

	pages_ptr = nfs_readdir_large_page(pages, array_size);

	if (!pages_ptr)

		goto out_release_array;

	do {

		status = nfs_readdir_xdr_filler(xdr_page, desc, &entry, file, inode);

		status = nfs_readdir_xdr_filler(pages, desc, &entry, file, inode);



		if (status < 0)

			break;

		nfs_readdir_page_filler(desc, &entry, xdr_page, page, array_size * PAGE_SIZE);

		nfs_readdir_page_filler(desc, &entry, pages_ptr, page, array_size * PAGE_SIZE);

	} while (array->eof_index < 0 && array->size < MAX_READDIR_ARRAY);



	put_page(xdr_page);

	nfs_readdir_free_large_page(pages_ptr, pages, array_size);

out_release_array:

	nfs_readdir_release_array(page);

out:

fs/nfs/internal.h

+6 −0
Original line number Diff line number Diff line
@@ -62,6 +62,12 @@ struct nfs_clone_mount { 
 */

#define NFS_UNSPEC_PORT		(-1)



/*

 * Maximum number of pages that readdir can use for creating

 * a vmapped array of pages.

 */

#define NFS_MAX_READDIR_PAGES 8



/*

 * In-kernel mount arguments

 */

fs/nfs/nfs3proc.c

+2 −2
Original line number Diff line number Diff line
@@ -630,7 +630,7 @@ nfs3_proc_rmdir(struct inode *dir, struct qstr *name) 
 */

static int

nfs3_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,

		  u64 cookie, struct page *page, unsigned int count, int plus)

		  u64 cookie, struct page **pages, unsigned int count, int plus)

{

	struct inode		*dir = dentry->d_inode;

	__be32			*verf = NFS_COOKIEVERF(dir);
@@ -640,7 +640,7 @@ nfs3_proc_readdir(struct dentry *dentry, struct rpc_cred *cred, 
		.verf		= {verf[0], verf[1]},

		.plus		= plus,

		.count		= count,

		.pages		= &page

		.pages		= pages

	};

	struct nfs3_readdirres	res = {

		.verf		= verf,

fs/nfs/nfs4proc.c

+4 −4
Original line number Diff line number Diff line
@@ -2823,12 +2823,12 @@ static int nfs4_proc_mkdir(struct inode *dir, struct dentry *dentry, 
}



static int _nfs4_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,

                  u64 cookie, struct page *page, unsigned int count, int plus)

		u64 cookie, struct page **pages, unsigned int count, int plus)

{

	struct inode		*dir = dentry->d_inode;

	struct nfs4_readdir_arg args = {

		.fh = NFS_FH(dir),

		.pages = &page,

		.pages = pages,

		.pgbase = 0,

		.count = count,

		.bitmask = NFS_SERVER(dentry->d_inode)->attr_bitmask,
@@ -2859,14 +2859,14 @@ static int _nfs4_proc_readdir(struct dentry *dentry, struct rpc_cred *cred, 
}



static int nfs4_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,

                  u64 cookie, struct page *page, unsigned int count, int plus)

		u64 cookie, struct page **pages, unsigned int count, int plus)

{

	struct nfs4_exception exception = { };

	int err;

	do {

		err = nfs4_handle_exception(NFS_SERVER(dentry->d_inode),

				_nfs4_proc_readdir(dentry, cred, cookie,

					page, count, plus),

					pages, count, plus),

				&exception);

	} while (exception.retry);

	return err;