nfsd4: reorganize write decoding

In preparation for moving some of it elsewhere.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
J. Bruce Fields 2012-11-16 10:01:30 -05:00
Родитель 8a61b18c9b
Коммит 5a80a54d21
1 изменённых файлов: 41 добавлений и 21 удалений

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@ -1139,12 +1139,30 @@ nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify
DECODE_TAIL;
}
static int fill_in_write_vector(struct kvec *vec, struct kvec *head, struct page **pagelist, int buflen)
{
int i = 1;
vec[0].iov_base = head->iov_base;
vec[0].iov_len = min_t(int, buflen, head->iov_len);
buflen -= vec[0].iov_len;
while (buflen) {
vec[i].iov_base = page_address(pagelist[i - 1]);
vec[i].iov_len = min_t(int, PAGE_SIZE, buflen);
buflen -= vec[i].iov_len;
i++;
}
return i;
}
static __be32
nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
{
int avail;
int v;
int len;
struct page **pagelist;
struct kvec head;
DECODE_HEAD;
status = nfsd4_decode_stateid(argp, &write->wr_stateid);
@ -1167,27 +1185,29 @@ nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
__FILE__, __LINE__);
goto xdr_error;
}
argp->rqstp->rq_vec[0].iov_base = p;
argp->rqstp->rq_vec[0].iov_len = avail;
v = 0;
len = write->wr_buflen;
while (len > argp->rqstp->rq_vec[v].iov_len) {
len -= argp->rqstp->rq_vec[v].iov_len;
v++;
argp->rqstp->rq_vec[v].iov_base = page_address(argp->pagelist[0]);
argp->pagelist++;
if (argp->pagelen >= PAGE_SIZE) {
argp->rqstp->rq_vec[v].iov_len = PAGE_SIZE;
argp->pagelen -= PAGE_SIZE;
} else {
argp->rqstp->rq_vec[v].iov_len = argp->pagelen;
argp->pagelen -= len;
}
head.iov_base = p;
head.iov_len = avail;
WARN_ON(avail != (XDR_QUADLEN(avail) << 2));
pagelist = argp->pagelist;
len = XDR_QUADLEN(write->wr_buflen) << 2;
if (len >= avail) {
int pages;
len -= avail;
pages = len >> PAGE_SHIFT;
argp->pagelist += pages;
argp->pagelen -= pages * PAGE_SIZE;
len -= pages * PAGE_SIZE;
argp->p = (__be32 *)page_address(argp->pagelist[0]);
argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
}
argp->end = (__be32*) (argp->rqstp->rq_vec[v].iov_base + argp->rqstp->rq_vec[v].iov_len);
argp->p = (__be32*) (argp->rqstp->rq_vec[v].iov_base + (XDR_QUADLEN(len) << 2));
argp->rqstp->rq_vec[v].iov_len = len;
write->wr_vlen = v+1;
argp->p += XDR_QUADLEN(len);
write->wr_vlen = fill_in_write_vector(argp->rqstp->rq_vec,
&head, pagelist, write->wr_buflen);
WARN_ON_ONCE(write->wr_vlen > ARRAY_SIZE(argp->rqstp->rq_vec));
DECODE_TAIL;
}