![Chuck Lever](/assets/img/avatar_default.png)
Move the bulk of client-side socket-specific code into a separate source file, net/sunrpc/xprtsock.c. Test-plan: Millions of fsx operations. Performance characterization such as "sio" or "iozone". Destructive testing (unplugging the network temporarily, server reboots). Connectathon with v2, v3, and v4. Version: Thu, 11 Aug 2005 16:03:38 -0400 Signed-off-by: Chuck Lever <cel@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
1022 lines
24 KiB
C
1022 lines
24 KiB
C
/*
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* linux/net/sunrpc/xdr.c
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*
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* Generic XDR support.
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*
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* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
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*/
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/string.h>
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#include <linux/kernel.h>
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#include <linux/pagemap.h>
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#include <linux/errno.h>
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#include <linux/sunrpc/xdr.h>
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#include <linux/sunrpc/msg_prot.h>
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/*
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* XDR functions for basic NFS types
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*/
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u32 *
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xdr_encode_netobj(u32 *p, const struct xdr_netobj *obj)
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{
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unsigned int quadlen = XDR_QUADLEN(obj->len);
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p[quadlen] = 0; /* zero trailing bytes */
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*p++ = htonl(obj->len);
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memcpy(p, obj->data, obj->len);
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return p + XDR_QUADLEN(obj->len);
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}
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u32 *
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xdr_decode_netobj(u32 *p, struct xdr_netobj *obj)
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{
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unsigned int len;
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if ((len = ntohl(*p++)) > XDR_MAX_NETOBJ)
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return NULL;
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obj->len = len;
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obj->data = (u8 *) p;
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return p + XDR_QUADLEN(len);
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}
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/**
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* xdr_encode_opaque_fixed - Encode fixed length opaque data
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* @p: pointer to current position in XDR buffer.
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* @ptr: pointer to data to encode (or NULL)
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* @nbytes: size of data.
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*
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* Copy the array of data of length nbytes at ptr to the XDR buffer
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* at position p, then align to the next 32-bit boundary by padding
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* with zero bytes (see RFC1832).
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* Note: if ptr is NULL, only the padding is performed.
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*
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* Returns the updated current XDR buffer position
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*
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*/
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u32 *xdr_encode_opaque_fixed(u32 *p, const void *ptr, unsigned int nbytes)
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{
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if (likely(nbytes != 0)) {
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unsigned int quadlen = XDR_QUADLEN(nbytes);
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unsigned int padding = (quadlen << 2) - nbytes;
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if (ptr != NULL)
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memcpy(p, ptr, nbytes);
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if (padding != 0)
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memset((char *)p + nbytes, 0, padding);
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p += quadlen;
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}
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return p;
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}
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EXPORT_SYMBOL(xdr_encode_opaque_fixed);
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/**
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* xdr_encode_opaque - Encode variable length opaque data
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* @p: pointer to current position in XDR buffer.
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* @ptr: pointer to data to encode (or NULL)
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* @nbytes: size of data.
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*
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* Returns the updated current XDR buffer position
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*/
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u32 *xdr_encode_opaque(u32 *p, const void *ptr, unsigned int nbytes)
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{
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*p++ = htonl(nbytes);
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return xdr_encode_opaque_fixed(p, ptr, nbytes);
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}
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EXPORT_SYMBOL(xdr_encode_opaque);
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u32 *
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xdr_encode_string(u32 *p, const char *string)
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{
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return xdr_encode_array(p, string, strlen(string));
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}
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u32 *
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xdr_decode_string(u32 *p, char **sp, int *lenp, int maxlen)
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{
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unsigned int len;
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char *string;
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if ((len = ntohl(*p++)) > maxlen)
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return NULL;
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if (lenp)
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*lenp = len;
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if ((len % 4) != 0) {
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string = (char *) p;
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} else {
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string = (char *) (p - 1);
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memmove(string, p, len);
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}
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string[len] = '\0';
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*sp = string;
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return p + XDR_QUADLEN(len);
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}
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u32 *
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xdr_decode_string_inplace(u32 *p, char **sp, int *lenp, int maxlen)
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{
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unsigned int len;
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if ((len = ntohl(*p++)) > maxlen)
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return NULL;
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*lenp = len;
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*sp = (char *) p;
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return p + XDR_QUADLEN(len);
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}
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void
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xdr_encode_pages(struct xdr_buf *xdr, struct page **pages, unsigned int base,
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unsigned int len)
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{
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struct kvec *tail = xdr->tail;
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u32 *p;
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xdr->pages = pages;
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xdr->page_base = base;
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xdr->page_len = len;
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p = (u32 *)xdr->head[0].iov_base + XDR_QUADLEN(xdr->head[0].iov_len);
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tail->iov_base = p;
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tail->iov_len = 0;
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if (len & 3) {
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unsigned int pad = 4 - (len & 3);
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*p = 0;
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tail->iov_base = (char *)p + (len & 3);
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tail->iov_len = pad;
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len += pad;
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}
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xdr->buflen += len;
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xdr->len += len;
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}
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void
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xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset,
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struct page **pages, unsigned int base, unsigned int len)
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{
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struct kvec *head = xdr->head;
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struct kvec *tail = xdr->tail;
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char *buf = (char *)head->iov_base;
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unsigned int buflen = head->iov_len;
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head->iov_len = offset;
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xdr->pages = pages;
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xdr->page_base = base;
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xdr->page_len = len;
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tail->iov_base = buf + offset;
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tail->iov_len = buflen - offset;
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xdr->buflen += len;
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}
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/*
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* Helper routines for doing 'memmove' like operations on a struct xdr_buf
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*
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* _shift_data_right_pages
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* @pages: vector of pages containing both the source and dest memory area.
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* @pgto_base: page vector address of destination
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* @pgfrom_base: page vector address of source
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* @len: number of bytes to copy
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*
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* Note: the addresses pgto_base and pgfrom_base are both calculated in
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* the same way:
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* if a memory area starts at byte 'base' in page 'pages[i]',
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* then its address is given as (i << PAGE_CACHE_SHIFT) + base
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* Also note: pgfrom_base must be < pgto_base, but the memory areas
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* they point to may overlap.
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*/
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static void
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_shift_data_right_pages(struct page **pages, size_t pgto_base,
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size_t pgfrom_base, size_t len)
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{
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struct page **pgfrom, **pgto;
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char *vfrom, *vto;
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size_t copy;
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BUG_ON(pgto_base <= pgfrom_base);
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pgto_base += len;
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pgfrom_base += len;
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pgto = pages + (pgto_base >> PAGE_CACHE_SHIFT);
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pgfrom = pages + (pgfrom_base >> PAGE_CACHE_SHIFT);
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pgto_base &= ~PAGE_CACHE_MASK;
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pgfrom_base &= ~PAGE_CACHE_MASK;
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do {
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/* Are any pointers crossing a page boundary? */
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if (pgto_base == 0) {
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flush_dcache_page(*pgto);
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pgto_base = PAGE_CACHE_SIZE;
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pgto--;
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}
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if (pgfrom_base == 0) {
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pgfrom_base = PAGE_CACHE_SIZE;
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pgfrom--;
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}
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copy = len;
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if (copy > pgto_base)
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copy = pgto_base;
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if (copy > pgfrom_base)
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copy = pgfrom_base;
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pgto_base -= copy;
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pgfrom_base -= copy;
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vto = kmap_atomic(*pgto, KM_USER0);
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vfrom = kmap_atomic(*pgfrom, KM_USER1);
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memmove(vto + pgto_base, vfrom + pgfrom_base, copy);
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kunmap_atomic(vfrom, KM_USER1);
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kunmap_atomic(vto, KM_USER0);
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} while ((len -= copy) != 0);
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flush_dcache_page(*pgto);
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}
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/*
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* _copy_to_pages
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* @pages: array of pages
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* @pgbase: page vector address of destination
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* @p: pointer to source data
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* @len: length
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*
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* Copies data from an arbitrary memory location into an array of pages
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* The copy is assumed to be non-overlapping.
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*/
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static void
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_copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len)
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{
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struct page **pgto;
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char *vto;
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size_t copy;
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pgto = pages + (pgbase >> PAGE_CACHE_SHIFT);
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pgbase &= ~PAGE_CACHE_MASK;
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do {
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copy = PAGE_CACHE_SIZE - pgbase;
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if (copy > len)
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copy = len;
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vto = kmap_atomic(*pgto, KM_USER0);
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memcpy(vto + pgbase, p, copy);
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kunmap_atomic(vto, KM_USER0);
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pgbase += copy;
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if (pgbase == PAGE_CACHE_SIZE) {
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flush_dcache_page(*pgto);
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pgbase = 0;
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pgto++;
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}
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p += copy;
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} while ((len -= copy) != 0);
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flush_dcache_page(*pgto);
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}
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/*
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* _copy_from_pages
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* @p: pointer to destination
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* @pages: array of pages
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* @pgbase: offset of source data
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* @len: length
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*
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* Copies data into an arbitrary memory location from an array of pages
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* The copy is assumed to be non-overlapping.
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*/
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static void
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_copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
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{
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struct page **pgfrom;
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char *vfrom;
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size_t copy;
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pgfrom = pages + (pgbase >> PAGE_CACHE_SHIFT);
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pgbase &= ~PAGE_CACHE_MASK;
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do {
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copy = PAGE_CACHE_SIZE - pgbase;
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if (copy > len)
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copy = len;
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vfrom = kmap_atomic(*pgfrom, KM_USER0);
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memcpy(p, vfrom + pgbase, copy);
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kunmap_atomic(vfrom, KM_USER0);
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pgbase += copy;
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if (pgbase == PAGE_CACHE_SIZE) {
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pgbase = 0;
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pgfrom++;
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}
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p += copy;
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} while ((len -= copy) != 0);
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}
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/*
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* xdr_shrink_bufhead
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* @buf: xdr_buf
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* @len: bytes to remove from buf->head[0]
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*
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* Shrinks XDR buffer's header kvec buf->head[0] by
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* 'len' bytes. The extra data is not lost, but is instead
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* moved into the inlined pages and/or the tail.
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*/
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static void
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xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
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{
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struct kvec *head, *tail;
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size_t copy, offs;
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unsigned int pglen = buf->page_len;
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tail = buf->tail;
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head = buf->head;
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BUG_ON (len > head->iov_len);
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/* Shift the tail first */
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if (tail->iov_len != 0) {
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if (tail->iov_len > len) {
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copy = tail->iov_len - len;
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memmove((char *)tail->iov_base + len,
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tail->iov_base, copy);
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}
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/* Copy from the inlined pages into the tail */
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copy = len;
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if (copy > pglen)
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copy = pglen;
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offs = len - copy;
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if (offs >= tail->iov_len)
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copy = 0;
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else if (copy > tail->iov_len - offs)
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copy = tail->iov_len - offs;
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if (copy != 0)
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_copy_from_pages((char *)tail->iov_base + offs,
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buf->pages,
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buf->page_base + pglen + offs - len,
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copy);
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/* Do we also need to copy data from the head into the tail ? */
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if (len > pglen) {
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offs = copy = len - pglen;
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if (copy > tail->iov_len)
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copy = tail->iov_len;
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memcpy(tail->iov_base,
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(char *)head->iov_base +
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head->iov_len - offs,
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copy);
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}
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}
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/* Now handle pages */
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if (pglen != 0) {
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if (pglen > len)
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_shift_data_right_pages(buf->pages,
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buf->page_base + len,
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buf->page_base,
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pglen - len);
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copy = len;
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if (len > pglen)
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copy = pglen;
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_copy_to_pages(buf->pages, buf->page_base,
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(char *)head->iov_base + head->iov_len - len,
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copy);
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}
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head->iov_len -= len;
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buf->buflen -= len;
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/* Have we truncated the message? */
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if (buf->len > buf->buflen)
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buf->len = buf->buflen;
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}
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/*
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* xdr_shrink_pagelen
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* @buf: xdr_buf
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* @len: bytes to remove from buf->pages
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*
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* Shrinks XDR buffer's page array buf->pages by
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* 'len' bytes. The extra data is not lost, but is instead
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* moved into the tail.
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*/
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static void
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xdr_shrink_pagelen(struct xdr_buf *buf, size_t len)
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{
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struct kvec *tail;
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size_t copy;
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char *p;
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unsigned int pglen = buf->page_len;
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tail = buf->tail;
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BUG_ON (len > pglen);
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/* Shift the tail first */
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if (tail->iov_len != 0) {
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p = (char *)tail->iov_base + len;
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if (tail->iov_len > len) {
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copy = tail->iov_len - len;
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memmove(p, tail->iov_base, copy);
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} else
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buf->buflen -= len;
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/* Copy from the inlined pages into the tail */
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copy = len;
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if (copy > tail->iov_len)
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copy = tail->iov_len;
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_copy_from_pages((char *)tail->iov_base,
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buf->pages, buf->page_base + pglen - len,
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copy);
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}
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buf->page_len -= len;
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buf->buflen -= len;
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/* Have we truncated the message? */
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if (buf->len > buf->buflen)
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buf->len = buf->buflen;
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}
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void
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xdr_shift_buf(struct xdr_buf *buf, size_t len)
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{
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xdr_shrink_bufhead(buf, len);
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}
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/**
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* xdr_init_encode - Initialize a struct xdr_stream for sending data.
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* @xdr: pointer to xdr_stream struct
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* @buf: pointer to XDR buffer in which to encode data
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* @p: current pointer inside XDR buffer
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*
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* Note: at the moment the RPC client only passes the length of our
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* scratch buffer in the xdr_buf's header kvec. Previously this
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* meant we needed to call xdr_adjust_iovec() after encoding the
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* data. With the new scheme, the xdr_stream manages the details
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* of the buffer length, and takes care of adjusting the kvec
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* length for us.
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*/
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void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, uint32_t *p)
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{
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struct kvec *iov = buf->head;
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int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len;
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BUG_ON(scratch_len < 0);
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xdr->buf = buf;
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xdr->iov = iov;
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xdr->p = (uint32_t *)((char *)iov->iov_base + iov->iov_len);
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xdr->end = (uint32_t *)((char *)iov->iov_base + scratch_len);
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BUG_ON(iov->iov_len > scratch_len);
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if (p != xdr->p && p != NULL) {
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size_t len;
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BUG_ON(p < xdr->p || p > xdr->end);
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len = (char *)p - (char *)xdr->p;
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xdr->p = p;
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buf->len += len;
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iov->iov_len += len;
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}
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}
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EXPORT_SYMBOL(xdr_init_encode);
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/**
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* xdr_reserve_space - Reserve buffer space for sending
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* @xdr: pointer to xdr_stream
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* @nbytes: number of bytes to reserve
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*
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* Checks that we have enough buffer space to encode 'nbytes' more
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* bytes of data. If so, update the total xdr_buf length, and
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* adjust the length of the current kvec.
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*/
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uint32_t * xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes)
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{
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uint32_t *p = xdr->p;
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uint32_t *q;
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/* align nbytes on the next 32-bit boundary */
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nbytes += 3;
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nbytes &= ~3;
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q = p + (nbytes >> 2);
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if (unlikely(q > xdr->end || q < p))
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return NULL;
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xdr->p = q;
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xdr->iov->iov_len += nbytes;
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xdr->buf->len += nbytes;
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return p;
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}
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EXPORT_SYMBOL(xdr_reserve_space);
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/**
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* xdr_write_pages - Insert a list of pages into an XDR buffer for sending
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* @xdr: pointer to xdr_stream
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* @pages: list of pages
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* @base: offset of first byte
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* @len: length of data in bytes
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*
|
|
*/
|
|
void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int base,
|
|
unsigned int len)
|
|
{
|
|
struct xdr_buf *buf = xdr->buf;
|
|
struct kvec *iov = buf->tail;
|
|
buf->pages = pages;
|
|
buf->page_base = base;
|
|
buf->page_len = len;
|
|
|
|
iov->iov_base = (char *)xdr->p;
|
|
iov->iov_len = 0;
|
|
xdr->iov = iov;
|
|
|
|
if (len & 3) {
|
|
unsigned int pad = 4 - (len & 3);
|
|
|
|
BUG_ON(xdr->p >= xdr->end);
|
|
iov->iov_base = (char *)xdr->p + (len & 3);
|
|
iov->iov_len += pad;
|
|
len += pad;
|
|
*xdr->p++ = 0;
|
|
}
|
|
buf->buflen += len;
|
|
buf->len += len;
|
|
}
|
|
EXPORT_SYMBOL(xdr_write_pages);
|
|
|
|
/**
|
|
* xdr_init_decode - Initialize an xdr_stream for decoding data.
|
|
* @xdr: pointer to xdr_stream struct
|
|
* @buf: pointer to XDR buffer from which to decode data
|
|
* @p: current pointer inside XDR buffer
|
|
*/
|
|
void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, uint32_t *p)
|
|
{
|
|
struct kvec *iov = buf->head;
|
|
unsigned int len = iov->iov_len;
|
|
|
|
if (len > buf->len)
|
|
len = buf->len;
|
|
xdr->buf = buf;
|
|
xdr->iov = iov;
|
|
xdr->p = p;
|
|
xdr->end = (uint32_t *)((char *)iov->iov_base + len);
|
|
}
|
|
EXPORT_SYMBOL(xdr_init_decode);
|
|
|
|
/**
|
|
* xdr_inline_decode - Retrieve non-page XDR data to decode
|
|
* @xdr: pointer to xdr_stream struct
|
|
* @nbytes: number of bytes of data to decode
|
|
*
|
|
* Check if the input buffer is long enough to enable us to decode
|
|
* 'nbytes' more bytes of data starting at the current position.
|
|
* If so return the current pointer, then update the current
|
|
* pointer position.
|
|
*/
|
|
uint32_t * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
|
|
{
|
|
uint32_t *p = xdr->p;
|
|
uint32_t *q = p + XDR_QUADLEN(nbytes);
|
|
|
|
if (unlikely(q > xdr->end || q < p))
|
|
return NULL;
|
|
xdr->p = q;
|
|
return p;
|
|
}
|
|
EXPORT_SYMBOL(xdr_inline_decode);
|
|
|
|
/**
|
|
* xdr_read_pages - Ensure page-based XDR data to decode is aligned at current pointer position
|
|
* @xdr: pointer to xdr_stream struct
|
|
* @len: number of bytes of page data
|
|
*
|
|
* Moves data beyond the current pointer position from the XDR head[] buffer
|
|
* into the page list. Any data that lies beyond current position + "len"
|
|
* bytes is moved into the XDR tail[]. The current pointer is then
|
|
* repositioned at the beginning of the XDR tail.
|
|
*/
|
|
void xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
|
|
{
|
|
struct xdr_buf *buf = xdr->buf;
|
|
struct kvec *iov;
|
|
ssize_t shift;
|
|
unsigned int end;
|
|
int padding;
|
|
|
|
/* Realign pages to current pointer position */
|
|
iov = buf->head;
|
|
shift = iov->iov_len + (char *)iov->iov_base - (char *)xdr->p;
|
|
if (shift > 0)
|
|
xdr_shrink_bufhead(buf, shift);
|
|
|
|
/* Truncate page data and move it into the tail */
|
|
if (buf->page_len > len)
|
|
xdr_shrink_pagelen(buf, buf->page_len - len);
|
|
padding = (XDR_QUADLEN(len) << 2) - len;
|
|
xdr->iov = iov = buf->tail;
|
|
/* Compute remaining message length. */
|
|
end = iov->iov_len;
|
|
shift = buf->buflen - buf->len;
|
|
if (shift < end)
|
|
end -= shift;
|
|
else if (shift > 0)
|
|
end = 0;
|
|
/*
|
|
* Position current pointer at beginning of tail, and
|
|
* set remaining message length.
|
|
*/
|
|
xdr->p = (uint32_t *)((char *)iov->iov_base + padding);
|
|
xdr->end = (uint32_t *)((char *)iov->iov_base + end);
|
|
}
|
|
EXPORT_SYMBOL(xdr_read_pages);
|
|
|
|
static struct kvec empty_iov = {.iov_base = NULL, .iov_len = 0};
|
|
|
|
void
|
|
xdr_buf_from_iov(struct kvec *iov, struct xdr_buf *buf)
|
|
{
|
|
buf->head[0] = *iov;
|
|
buf->tail[0] = empty_iov;
|
|
buf->page_len = 0;
|
|
buf->buflen = buf->len = iov->iov_len;
|
|
}
|
|
|
|
/* Sets subiov to the intersection of iov with the buffer of length len
|
|
* starting base bytes after iov. Indicates empty intersection by setting
|
|
* length of subiov to zero. Decrements len by length of subiov, sets base
|
|
* to zero (or decrements it by length of iov if subiov is empty). */
|
|
static void
|
|
iov_subsegment(struct kvec *iov, struct kvec *subiov, int *base, int *len)
|
|
{
|
|
if (*base > iov->iov_len) {
|
|
subiov->iov_base = NULL;
|
|
subiov->iov_len = 0;
|
|
*base -= iov->iov_len;
|
|
} else {
|
|
subiov->iov_base = iov->iov_base + *base;
|
|
subiov->iov_len = min(*len, (int)iov->iov_len - *base);
|
|
*base = 0;
|
|
}
|
|
*len -= subiov->iov_len;
|
|
}
|
|
|
|
/* Sets subbuf to the portion of buf of length len beginning base bytes
|
|
* from the start of buf. Returns -1 if base of length are out of bounds. */
|
|
int
|
|
xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf,
|
|
int base, int len)
|
|
{
|
|
int i;
|
|
|
|
subbuf->buflen = subbuf->len = len;
|
|
iov_subsegment(buf->head, subbuf->head, &base, &len);
|
|
|
|
if (base < buf->page_len) {
|
|
i = (base + buf->page_base) >> PAGE_CACHE_SHIFT;
|
|
subbuf->pages = &buf->pages[i];
|
|
subbuf->page_base = (base + buf->page_base) & ~PAGE_CACHE_MASK;
|
|
subbuf->page_len = min((int)buf->page_len - base, len);
|
|
len -= subbuf->page_len;
|
|
base = 0;
|
|
} else {
|
|
base -= buf->page_len;
|
|
subbuf->page_len = 0;
|
|
}
|
|
|
|
iov_subsegment(buf->tail, subbuf->tail, &base, &len);
|
|
if (base || len)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
/* obj is assumed to point to allocated memory of size at least len: */
|
|
int
|
|
read_bytes_from_xdr_buf(struct xdr_buf *buf, int base, void *obj, int len)
|
|
{
|
|
struct xdr_buf subbuf;
|
|
int this_len;
|
|
int status;
|
|
|
|
status = xdr_buf_subsegment(buf, &subbuf, base, len);
|
|
if (status)
|
|
goto out;
|
|
this_len = min(len, (int)subbuf.head[0].iov_len);
|
|
memcpy(obj, subbuf.head[0].iov_base, this_len);
|
|
len -= this_len;
|
|
obj += this_len;
|
|
this_len = min(len, (int)subbuf.page_len);
|
|
if (this_len)
|
|
_copy_from_pages(obj, subbuf.pages, subbuf.page_base, this_len);
|
|
len -= this_len;
|
|
obj += this_len;
|
|
this_len = min(len, (int)subbuf.tail[0].iov_len);
|
|
memcpy(obj, subbuf.tail[0].iov_base, this_len);
|
|
out:
|
|
return status;
|
|
}
|
|
|
|
/* obj is assumed to point to allocated memory of size at least len: */
|
|
int
|
|
write_bytes_to_xdr_buf(struct xdr_buf *buf, int base, void *obj, int len)
|
|
{
|
|
struct xdr_buf subbuf;
|
|
int this_len;
|
|
int status;
|
|
|
|
status = xdr_buf_subsegment(buf, &subbuf, base, len);
|
|
if (status)
|
|
goto out;
|
|
this_len = min(len, (int)subbuf.head[0].iov_len);
|
|
memcpy(subbuf.head[0].iov_base, obj, this_len);
|
|
len -= this_len;
|
|
obj += this_len;
|
|
this_len = min(len, (int)subbuf.page_len);
|
|
if (this_len)
|
|
_copy_to_pages(subbuf.pages, subbuf.page_base, obj, this_len);
|
|
len -= this_len;
|
|
obj += this_len;
|
|
this_len = min(len, (int)subbuf.tail[0].iov_len);
|
|
memcpy(subbuf.tail[0].iov_base, obj, this_len);
|
|
out:
|
|
return status;
|
|
}
|
|
|
|
int
|
|
xdr_decode_word(struct xdr_buf *buf, int base, u32 *obj)
|
|
{
|
|
u32 raw;
|
|
int status;
|
|
|
|
status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
|
|
if (status)
|
|
return status;
|
|
*obj = ntohl(raw);
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
xdr_encode_word(struct xdr_buf *buf, int base, u32 obj)
|
|
{
|
|
u32 raw = htonl(obj);
|
|
|
|
return write_bytes_to_xdr_buf(buf, base, &raw, sizeof(obj));
|
|
}
|
|
|
|
/* If the netobj starting offset bytes from the start of xdr_buf is contained
|
|
* entirely in the head or the tail, set object to point to it; otherwise
|
|
* try to find space for it at the end of the tail, copy it there, and
|
|
* set obj to point to it. */
|
|
int
|
|
xdr_buf_read_netobj(struct xdr_buf *buf, struct xdr_netobj *obj, int offset)
|
|
{
|
|
u32 tail_offset = buf->head[0].iov_len + buf->page_len;
|
|
u32 obj_end_offset;
|
|
|
|
if (xdr_decode_word(buf, offset, &obj->len))
|
|
goto out;
|
|
obj_end_offset = offset + 4 + obj->len;
|
|
|
|
if (obj_end_offset <= buf->head[0].iov_len) {
|
|
/* The obj is contained entirely in the head: */
|
|
obj->data = buf->head[0].iov_base + offset + 4;
|
|
} else if (offset + 4 >= tail_offset) {
|
|
if (obj_end_offset - tail_offset
|
|
> buf->tail[0].iov_len)
|
|
goto out;
|
|
/* The obj is contained entirely in the tail: */
|
|
obj->data = buf->tail[0].iov_base
|
|
+ offset - tail_offset + 4;
|
|
} else {
|
|
/* use end of tail as storage for obj:
|
|
* (We don't copy to the beginning because then we'd have
|
|
* to worry about doing a potentially overlapping copy.
|
|
* This assumes the object is at most half the length of the
|
|
* tail.) */
|
|
if (obj->len > buf->tail[0].iov_len)
|
|
goto out;
|
|
obj->data = buf->tail[0].iov_base + buf->tail[0].iov_len -
|
|
obj->len;
|
|
if (read_bytes_from_xdr_buf(buf, offset + 4,
|
|
obj->data, obj->len))
|
|
goto out;
|
|
|
|
}
|
|
return 0;
|
|
out:
|
|
return -1;
|
|
}
|
|
|
|
/* Returns 0 on success, or else a negative error code. */
|
|
static int
|
|
xdr_xcode_array2(struct xdr_buf *buf, unsigned int base,
|
|
struct xdr_array2_desc *desc, int encode)
|
|
{
|
|
char *elem = NULL, *c;
|
|
unsigned int copied = 0, todo, avail_here;
|
|
struct page **ppages = NULL;
|
|
int err;
|
|
|
|
if (encode) {
|
|
if (xdr_encode_word(buf, base, desc->array_len) != 0)
|
|
return -EINVAL;
|
|
} else {
|
|
if (xdr_decode_word(buf, base, &desc->array_len) != 0 ||
|
|
desc->array_len > desc->array_maxlen ||
|
|
(unsigned long) base + 4 + desc->array_len *
|
|
desc->elem_size > buf->len)
|
|
return -EINVAL;
|
|
}
|
|
base += 4;
|
|
|
|
if (!desc->xcode)
|
|
return 0;
|
|
|
|
todo = desc->array_len * desc->elem_size;
|
|
|
|
/* process head */
|
|
if (todo && base < buf->head->iov_len) {
|
|
c = buf->head->iov_base + base;
|
|
avail_here = min_t(unsigned int, todo,
|
|
buf->head->iov_len - base);
|
|
todo -= avail_here;
|
|
|
|
while (avail_here >= desc->elem_size) {
|
|
err = desc->xcode(desc, c);
|
|
if (err)
|
|
goto out;
|
|
c += desc->elem_size;
|
|
avail_here -= desc->elem_size;
|
|
}
|
|
if (avail_here) {
|
|
if (!elem) {
|
|
elem = kmalloc(desc->elem_size, GFP_KERNEL);
|
|
err = -ENOMEM;
|
|
if (!elem)
|
|
goto out;
|
|
}
|
|
if (encode) {
|
|
err = desc->xcode(desc, elem);
|
|
if (err)
|
|
goto out;
|
|
memcpy(c, elem, avail_here);
|
|
} else
|
|
memcpy(elem, c, avail_here);
|
|
copied = avail_here;
|
|
}
|
|
base = buf->head->iov_len; /* align to start of pages */
|
|
}
|
|
|
|
/* process pages array */
|
|
base -= buf->head->iov_len;
|
|
if (todo && base < buf->page_len) {
|
|
unsigned int avail_page;
|
|
|
|
avail_here = min(todo, buf->page_len - base);
|
|
todo -= avail_here;
|
|
|
|
base += buf->page_base;
|
|
ppages = buf->pages + (base >> PAGE_CACHE_SHIFT);
|
|
base &= ~PAGE_CACHE_MASK;
|
|
avail_page = min_t(unsigned int, PAGE_CACHE_SIZE - base,
|
|
avail_here);
|
|
c = kmap(*ppages) + base;
|
|
|
|
while (avail_here) {
|
|
avail_here -= avail_page;
|
|
if (copied || avail_page < desc->elem_size) {
|
|
unsigned int l = min(avail_page,
|
|
desc->elem_size - copied);
|
|
if (!elem) {
|
|
elem = kmalloc(desc->elem_size,
|
|
GFP_KERNEL);
|
|
err = -ENOMEM;
|
|
if (!elem)
|
|
goto out;
|
|
}
|
|
if (encode) {
|
|
if (!copied) {
|
|
err = desc->xcode(desc, elem);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
memcpy(c, elem + copied, l);
|
|
copied += l;
|
|
if (copied == desc->elem_size)
|
|
copied = 0;
|
|
} else {
|
|
memcpy(elem + copied, c, l);
|
|
copied += l;
|
|
if (copied == desc->elem_size) {
|
|
err = desc->xcode(desc, elem);
|
|
if (err)
|
|
goto out;
|
|
copied = 0;
|
|
}
|
|
}
|
|
avail_page -= l;
|
|
c += l;
|
|
}
|
|
while (avail_page >= desc->elem_size) {
|
|
err = desc->xcode(desc, c);
|
|
if (err)
|
|
goto out;
|
|
c += desc->elem_size;
|
|
avail_page -= desc->elem_size;
|
|
}
|
|
if (avail_page) {
|
|
unsigned int l = min(avail_page,
|
|
desc->elem_size - copied);
|
|
if (!elem) {
|
|
elem = kmalloc(desc->elem_size,
|
|
GFP_KERNEL);
|
|
err = -ENOMEM;
|
|
if (!elem)
|
|
goto out;
|
|
}
|
|
if (encode) {
|
|
if (!copied) {
|
|
err = desc->xcode(desc, elem);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
memcpy(c, elem + copied, l);
|
|
copied += l;
|
|
if (copied == desc->elem_size)
|
|
copied = 0;
|
|
} else {
|
|
memcpy(elem + copied, c, l);
|
|
copied += l;
|
|
if (copied == desc->elem_size) {
|
|
err = desc->xcode(desc, elem);
|
|
if (err)
|
|
goto out;
|
|
copied = 0;
|
|
}
|
|
}
|
|
}
|
|
if (avail_here) {
|
|
kunmap(*ppages);
|
|
ppages++;
|
|
c = kmap(*ppages);
|
|
}
|
|
|
|
avail_page = min(avail_here,
|
|
(unsigned int) PAGE_CACHE_SIZE);
|
|
}
|
|
base = buf->page_len; /* align to start of tail */
|
|
}
|
|
|
|
/* process tail */
|
|
base -= buf->page_len;
|
|
if (todo) {
|
|
c = buf->tail->iov_base + base;
|
|
if (copied) {
|
|
unsigned int l = desc->elem_size - copied;
|
|
|
|
if (encode)
|
|
memcpy(c, elem + copied, l);
|
|
else {
|
|
memcpy(elem + copied, c, l);
|
|
err = desc->xcode(desc, elem);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
todo -= l;
|
|
c += l;
|
|
}
|
|
while (todo) {
|
|
err = desc->xcode(desc, c);
|
|
if (err)
|
|
goto out;
|
|
c += desc->elem_size;
|
|
todo -= desc->elem_size;
|
|
}
|
|
}
|
|
err = 0;
|
|
|
|
out:
|
|
if (elem)
|
|
kfree(elem);
|
|
if (ppages)
|
|
kunmap(*ppages);
|
|
return err;
|
|
}
|
|
|
|
int
|
|
xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
|
|
struct xdr_array2_desc *desc)
|
|
{
|
|
if (base >= buf->len)
|
|
return -EINVAL;
|
|
|
|
return xdr_xcode_array2(buf, base, desc, 0);
|
|
}
|
|
|
|
int
|
|
xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
|
|
struct xdr_array2_desc *desc)
|
|
{
|
|
if ((unsigned long) base + 4 + desc->array_len * desc->elem_size >
|
|
buf->head->iov_len + buf->page_len + buf->tail->iov_len)
|
|
return -EINVAL;
|
|
|
|
return xdr_xcode_array2(buf, base, desc, 1);
|
|
}
|