5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Chuck Lever chuck.lever@oracle.com
[ Upstream commit c1346a1216ab5cb04a265380ac9035d91b16b6d5 ]
Convert the READ_BUF macro in nfs4xdr.c from open code to instead use the new xdr_stream-style decoders already in use by the encode side (and by the in-kernel NFS client implementation). Once this conversion is done, each individual NFSv4 argument decoder can be independently cleaned up to replace these macros with C code.
Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/nfs4proc.c | 4 +- fs/nfsd/nfs4xdr.c | 181 ++++++------------------------------- fs/nfsd/xdr4.h | 10 +- include/linux/sunrpc/xdr.h | 2 + net/sunrpc/xdr.c | 45 +++++++++ 5 files changed, 77 insertions(+), 165 deletions(-)
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 55a46e7c152b9..95545a61bfc77 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1024,8 +1024,8 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
write->wr_how_written = write->wr_stable_how;
- nvecs = svc_fill_write_vector(rqstp, write->wr_pagelist, - &write->wr_head, write->wr_buflen); + nvecs = svc_fill_write_vector(rqstp, write->wr_payload.pages, + write->wr_payload.head, write->wr_buflen); WARN_ON_ONCE(nvecs > ARRAY_SIZE(rqstp->rq_vec));
status = nfsd_vfs_write(rqstp, &cstate->current_fh, nf, diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 101ada3636b78..8c694844f0efb 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -131,90 +131,13 @@ xdr_error: \ memcpy((x), p, nbytes); \ p += XDR_QUADLEN(nbytes); \ } while (0) - -/* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */ -#define READ_BUF(nbytes) do { \ - if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) { \ - p = argp->p; \ - argp->p += XDR_QUADLEN(nbytes); \ - } else if (!(p = read_buf(argp, nbytes))) { \ - dprintk("NFSD: xdr error (%s:%d)\n", \ - __FILE__, __LINE__); \ - goto xdr_error; \ - } \ -} while (0) - -static void next_decode_page(struct nfsd4_compoundargs *argp) -{ - argp->p = page_address(argp->pagelist[0]); - argp->pagelist++; - if (argp->pagelen < PAGE_SIZE) { - argp->end = argp->p + XDR_QUADLEN(argp->pagelen); - argp->pagelen = 0; - } else { - argp->end = argp->p + (PAGE_SIZE>>2); - argp->pagelen -= PAGE_SIZE; - } -} - -static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes) -{ - /* We want more bytes than seem to be available. - * Maybe we need a new page, maybe we have just run out - */ - unsigned int avail = (char *)argp->end - (char *)argp->p; - __be32 *p; - - if (argp->pagelen == 0) { - struct kvec *vec = &argp->rqstp->rq_arg.tail[0]; - - if (!argp->tail) { - argp->tail = true; - avail = vec->iov_len; - argp->p = vec->iov_base; - argp->end = vec->iov_base + avail; - } - - if (avail < nbytes) - return NULL; - - p = argp->p; - argp->p += XDR_QUADLEN(nbytes); - return p; - } - - if (avail + argp->pagelen < nbytes) - return NULL; - if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */ - return NULL; - /* ok, we can do it with the current plus the next page */ - if (nbytes <= sizeof(argp->tmp)) - p = argp->tmp; - else { - kfree(argp->tmpp); - p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL); - if (!p) - return NULL; - - } - /* - * The following memcpy is safe because read_buf is always - * called with nbytes > avail, and the two cases above both - * guarantee p points to at least nbytes bytes. - */ - memcpy(p, argp->p, avail); - next_decode_page(argp); - memcpy(((char*)p)+avail, argp->p, (nbytes - avail)); - argp->p += XDR_QUADLEN(nbytes - avail); - return p; -} - -static unsigned int compoundargs_bytes_left(struct nfsd4_compoundargs *argp) -{ - unsigned int this = (char *)argp->end - (char *)argp->p; - - return this + argp->pagelen; -} +#define READ_BUF(nbytes) \ + do { \ + p = xdr_inline_decode(argp->xdr,\ + nbytes); \ + if (!p) \ + goto xdr_error; \ + } while (0)
static int zero_clientid(clientid_t *clid) { @@ -261,44 +184,6 @@ svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len) return p; }
-static __be32 -svcxdr_construct_vector(struct nfsd4_compoundargs *argp, struct kvec *head, - struct page ***pagelist, u32 buflen) -{ - int avail; - int len; - int pages; - - /* Sorry .. no magic macros for this.. * - * READ_BUF(write->wr_buflen); - * SAVEMEM(write->wr_buf, write->wr_buflen); - */ - avail = (char *)argp->end - (char *)argp->p; - if (avail + argp->pagelen < buflen) { - dprintk("NFSD: xdr error (%s:%d)\n", - __FILE__, __LINE__); - return nfserr_bad_xdr; - } - head->iov_base = argp->p; - head->iov_len = avail; - *pagelist = argp->pagelist; - - len = XDR_QUADLEN(buflen) << 2; - if (len >= avail) { - len -= avail; - - pages = len >> PAGE_SHIFT; - argp->pagelist += pages; - argp->pagelen -= pages * PAGE_SIZE; - len -= pages * PAGE_SIZE; - - next_decode_page(argp); - } - argp->p += XDR_QUADLEN(len); - - return 0; -} - /** * savemem - duplicate a chunk of memory for later processing * @argp: NFSv4 compound argument structure to be freed with @@ -398,7 +283,7 @@ nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval, READ_BUF(4); len += 4; nace = be32_to_cpup(p++);
- if (nace > compoundargs_bytes_left(argp)/20) + if (nace > xdr_stream_remaining(argp->xdr) / sizeof(struct nfs4_ace)) /* * Even with 4-byte names there wouldn't be * space for that many aces; something fishy is @@ -929,7 +814,7 @@ static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o) { - __be32 *p; + DECODE_HEAD;
READ_BUF(4); o->len = be32_to_cpup(p++); @@ -939,9 +824,8 @@ static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_ne
READ_BUF(o->len); SAVEMEM(o->data, o->len); - return nfs_ok; -xdr_error: - return nfserr_bad_xdr; + + DECODE_TAIL; }
static __be32 @@ -1319,10 +1203,8 @@ nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write) goto xdr_error; write->wr_buflen = be32_to_cpup(p++);
- status = svcxdr_construct_vector(argp, &write->wr_head, - &write->wr_pagelist, write->wr_buflen); - if (status) - return status; + if (!xdr_stream_subsegment(argp->xdr, &write->wr_payload, write->wr_buflen)) + goto xdr_error;
DECODE_TAIL; } @@ -1891,13 +1773,14 @@ nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek) */
/* - * Decode data into buffer. Uses head and pages constructed by - * svcxdr_construct_vector. + * Decode data into buffer. */ static __be32 -nfsd4_vbuf_from_vector(struct nfsd4_compoundargs *argp, struct kvec *head, - struct page **pages, char **bufp, u32 buflen) +nfsd4_vbuf_from_vector(struct nfsd4_compoundargs *argp, struct xdr_buf *xdr, + char **bufp, u32 buflen) { + struct page **pages = xdr->pages; + struct kvec *head = xdr->head; char *tmp, *dp; u32 len;
@@ -2012,8 +1895,6 @@ nfsd4_decode_setxattr(struct nfsd4_compoundargs *argp, { DECODE_HEAD; u32 flags, maxcount, size; - struct kvec head; - struct page **pagelist;
READ_BUF(4); flags = be32_to_cpup(p++); @@ -2036,12 +1917,12 @@ nfsd4_decode_setxattr(struct nfsd4_compoundargs *argp,
setxattr->setxa_len = size; if (size > 0) { - status = svcxdr_construct_vector(argp, &head, &pagelist, size); - if (status) - return status; + struct xdr_buf payload;
- status = nfsd4_vbuf_from_vector(argp, &head, pagelist, - &setxattr->setxa_buf, size); + if (!xdr_stream_subsegment(argp->xdr, &payload, size)) + goto xdr_error; + status = nfsd4_vbuf_from_vector(argp, &payload, + &setxattr->setxa_buf, size); }
DECODE_TAIL; @@ -5305,8 +5186,6 @@ void nfsd4_release_compoundargs(struct svc_rqst *rqstp) kfree(args->ops); args->ops = args->iops; } - kfree(args->tmpp); - args->tmpp = NULL; while (args->to_free) { struct svcxdr_tmpbuf *tb = args->to_free; args->to_free = tb->next; @@ -5319,19 +5198,11 @@ nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p) { struct nfsd4_compoundargs *args = rqstp->rq_argp;
- if (rqstp->rq_arg.head[0].iov_len % 4) { - /* client is nuts */ - dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)", - __func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid)); - return 0; - } - args->p = p; - args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len; - args->pagelist = rqstp->rq_arg.pages; - args->pagelen = rqstp->rq_arg.page_len; - args->tail = false; + /* svcxdr_tmp_alloc */ args->tmpp = NULL; args->to_free = NULL; + + args->xdr = &rqstp->rq_arg_stream; args->ops = args->iops; args->rqstp = rqstp;
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h index 37f89ad5e9923..0eb13bd603ea6 100644 --- a/fs/nfsd/xdr4.h +++ b/fs/nfsd/xdr4.h @@ -419,8 +419,7 @@ struct nfsd4_write { u64 wr_offset; /* request */ u32 wr_stable_how; /* request */ u32 wr_buflen; /* request */ - struct kvec wr_head; - struct page ** wr_pagelist; /* request */ + struct xdr_buf wr_payload; /* request */
u32 wr_bytes_written; /* response */ u32 wr_how_written; /* response */ @@ -696,15 +695,10 @@ struct svcxdr_tmpbuf {
struct nfsd4_compoundargs { /* scratch variables for XDR decode */ - __be32 * p; - __be32 * end; - struct page ** pagelist; - int pagelen; - bool tail; __be32 tmp[8]; __be32 * tmpp; + struct xdr_stream *xdr; struct svcxdr_tmpbuf *to_free; - struct svc_rqst *rqstp;
u32 taglen; diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h index 0c8cab6210b3b..c03f7bf585c96 100644 --- a/include/linux/sunrpc/xdr.h +++ b/include/linux/sunrpc/xdr.h @@ -252,6 +252,8 @@ extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len); extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data); extern uint64_t xdr_align_data(struct xdr_stream *, uint64_t, uint32_t); extern uint64_t xdr_expand_hole(struct xdr_stream *, uint64_t, uint64_t); +extern bool xdr_stream_subsegment(struct xdr_stream *xdr, struct xdr_buf *subbuf, + unsigned int len);
/** * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data. diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c index 02adc5c7f034d..722586696fade 100644 --- a/net/sunrpc/xdr.c +++ b/net/sunrpc/xdr.c @@ -1412,6 +1412,51 @@ xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf, } EXPORT_SYMBOL_GPL(xdr_buf_subsegment);
+/** + * xdr_stream_subsegment - set @subbuf to a portion of @xdr + * @xdr: an xdr_stream set up for decoding + * @subbuf: the result buffer + * @nbytes: length of @xdr to extract, in bytes + * + * Sets up @subbuf to represent a portion of @xdr. The portion + * starts at the current offset in @xdr, and extends for a length + * of @nbytes. If this is successful, @xdr is advanced to the next + * position following that portion. + * + * Return values: + * %true: @subbuf has been initialized, and @xdr has been advanced. + * %false: a bounds error has occurred + */ +bool xdr_stream_subsegment(struct xdr_stream *xdr, struct xdr_buf *subbuf, + unsigned int nbytes) +{ + unsigned int remaining, offset, len; + + if (xdr_buf_subsegment(xdr->buf, subbuf, xdr_stream_pos(xdr), nbytes)) + return false; + + if (subbuf->head[0].iov_len) + if (!__xdr_inline_decode(xdr, subbuf->head[0].iov_len)) + return false; + + remaining = subbuf->page_len; + offset = subbuf->page_base; + while (remaining) { + len = min_t(unsigned int, remaining, PAGE_SIZE) - offset; + + if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr)) + return false; + if (!__xdr_inline_decode(xdr, len)) + return false; + + remaining -= len; + offset = 0; + } + + return true; +} +EXPORT_SYMBOL_GPL(xdr_stream_subsegment); + /** * xdr_buf_trim - lop at most "len" bytes off the end of "buf" * @buf: buf to be trimmed