Commit 1a34c8c9 authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFS: Support larger readdir buffers 



Support readdir buffers of up to 1MB in size so that we can read
large directories using few RPC calls.

Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: default avatarBenjamin Coddington <bcodding@redhat.com>
Tested-by: default avatarBenjamin Coddington <bcodding@redhat.com>
Tested-by: default avatarDave Wysochanski <dwysocha@redhat.com>
parent a52a8a6a

fs/nfs/client.c

+2 −2
Original line number Diff line number Diff line
@@ -781,8 +781,8 @@ static void nfs_server_set_fsinfo(struct nfs_server *server, 
	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);



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

	if (server->dtsize > PAGE_SIZE * NFS_MAX_READDIR_PAGES)

		server->dtsize = PAGE_SIZE * NFS_MAX_READDIR_PAGES;

	if (server->dtsize > NFS_MAX_FILE_IO_SIZE)

		server->dtsize = NFS_MAX_FILE_IO_SIZE;

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

		server->dtsize = server->rsize;

fs/nfs/dir.c

+19 −14
Original line number Diff line number Diff line
@@ -727,44 +727,47 @@ static int nfs_readdir_page_filler(struct nfs_readdir_descriptor *desc, 
	return status;

}



static

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

static void nfs_readdir_free_pages(struct page **pages, size_t npages)

{

	unsigned int i;

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

		put_page(pages[i]);

	while (npages--)

		put_page(pages[npages]);

	kfree(pages);

}



/*

 * nfs_readdir_alloc_pages() will allocate pages that must be freed with a call

 * to nfs_readdir_free_pages()

 */

static

int nfs_readdir_alloc_pages(struct page **pages, unsigned int npages)

static struct page **nfs_readdir_alloc_pages(size_t npages)

{

	unsigned int i;

	struct page **pages;

	size_t i;



	pages = kmalloc_array(npages, sizeof(*pages), GFP_KERNEL);

	if (!pages)

		return NULL;

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

		struct page *page = alloc_page(GFP_KERNEL);

		if (page == NULL)

			goto out_freepages;

		pages[i] = page;

	}

	return 0;

	return pages;



out_freepages:

	nfs_readdir_free_pages(pages, i);

	return -ENOMEM;

	return NULL;

}



static

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

{

	struct page *pages[NFS_MAX_READDIR_PAGES];

	struct page **pages;

	struct nfs_entry entry;

	struct file	*file = desc->file;

	size_t array_size;

	size_t dtsize = NFS_SERVER(inode)->dtsize;

	int status = -ENOMEM;

	unsigned int array_size = ARRAY_SIZE(pages);



	entry.prev_cookie = 0;

	entry.cookie = nfs_readdir_page_last_cookie(page);
@@ -781,9 +784,11 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, 
		goto out;

	}



	status = nfs_readdir_alloc_pages(pages, array_size);

	if (status < 0)

	array_size = (dtsize + PAGE_SIZE - 1) >> PAGE_SHIFT;

	pages = nfs_readdir_alloc_pages(array_size);

	if (!pages)

		goto out_release_label;



	do {

		unsigned int pglen;

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

fs/nfs/internal.h

+0 −6
Original line number Diff line number Diff line
@@ -56,12 +56,6 @@ static inline bool nfs_lookup_is_soft_revalidate(const struct dentry *dentry) 
#define NFS_UNSPEC_RETRANS	(UINT_MAX)

#define NFS_UNSPEC_TIMEO	(UINT_MAX)



/*

 * Maximum number of pages that readdir can use for creating

 * a vmapped array of pages.

 */

#define NFS_MAX_READDIR_PAGES 8



struct nfs_client_initdata {

	unsigned long init_flags;

	const char *hostname;			/* Hostname of the server */