[PATCH 05/24] afs: Set up the iov_iter before calling afs_extract_data()

From: David Howells
Date: Fri Oct 19 2018 - 21:11:20 EST

afs_extract_data sets up a temporary iov_iter and passes it to AF_RXRPC
each time it is called to describe the remaining buffer to be filled.

Instead:

(1) Put an iterator in the afs_call struct.

(2) Set the iterator for each marshalling stage to load data into the
appropriate places. A number of convenience functions are provided to
this end (eg. afs_extract_to_buf()).

This iterator is then passed to afs_extract_data().

(3) Use the new ITER_DISCARD iterator to discard any excess data provided
by FetchData.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

fs/afs/cmservice.c | 40 +++---
fs/afs/fsclient.c | 282 +++++++++++++++-----------------------------
fs/afs/internal.h | 56 ++++++++-
fs/afs/rxrpc.c | 41 ++----
fs/afs/vlclient.c | 104 +++++++---------
include/trace/events/afs.h | 22 ++-
6 files changed, 236 insertions(+), 309 deletions(-)

diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
index 58f79301a716..4db62ae8dc1a 100644
--- a/fs/afs/cmservice.c
+++ b/fs/afs/cmservice.c
@@ -176,13 +176,13 @@ static int afs_deliver_cb_callback(struct afs_call *call)

switch (call->unmarshall) {
case 0:
- call->offset = 0;
+ afs_extract_to_tmp(call);
call->unmarshall++;

/* extract the FID array and its count in two steps */
case 1:
_debug("extract FID count");
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -196,13 +196,12 @@ static int afs_deliver_cb_callback(struct afs_call *call)
GFP_KERNEL);
if (!call->buffer)
return -ENOMEM;
- call->offset = 0;
+ afs_extract_to_buf(call, call->count * 3 * 4);
call->unmarshall++;

case 2:
_debug("extract FID array");
- ret = afs_extract_data(call, call->buffer,
- call->count * 3 * 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -222,13 +221,13 @@ static int afs_deliver_cb_callback(struct afs_call *call)
cb->cb.type = AFSCM_CB_UNTYPED;
}

- call->offset = 0;
+ afs_extract_to_tmp(call);
call->unmarshall++;

/* extract the callback array and its count in two steps */
case 3:
_debug("extract CB count");
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -237,13 +236,12 @@ static int afs_deliver_cb_callback(struct afs_call *call)
if (call->count2 != call->count && call->count2 != 0)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_cb_count);
- call->offset = 0;
+ afs_extract_to_buf(call, call->count2 * 3 * 4);
call->unmarshall++;

case 4:
_debug("extract CB array");
- ret = afs_extract_data(call, call->buffer,
- call->count2 * 3 * 4, false);
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;

@@ -256,7 +254,6 @@ static int afs_deliver_cb_callback(struct afs_call *call)
cb->cb.type = ntohl(*bp++);
}

- call->offset = 0;
call->unmarshall++;
case 5:
break;
@@ -303,7 +300,8 @@ static int afs_deliver_cb_init_call_back_state(struct afs_call *call)

rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);

- ret = afs_extract_data(call, NULL, 0, false);
+ afs_extract_discard(call, 0);
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;

@@ -332,16 +330,15 @@ static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)

switch (call->unmarshall) {
case 0:
- call->offset = 0;
call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
if (!call->buffer)
return -ENOMEM;
+ afs_extract_to_buf(call, 11 * sizeof(__be32));
call->unmarshall++;

case 1:
_debug("extract UUID");
- ret = afs_extract_data(call, call->buffer,
- 11 * sizeof(__be32), false);
+ ret = afs_extract_data(call, false);
switch (ret) {
case 0: break;
case -EAGAIN: return 0;
@@ -364,7 +361,6 @@ static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
for (loop = 0; loop < 6; loop++)
r->node[loop] = ntohl(b[loop + 5]);

- call->offset = 0;
call->unmarshall++;

case 2:
@@ -407,7 +403,8 @@ static int afs_deliver_cb_probe(struct afs_call *call)

_enter("");

- ret = afs_extract_data(call, NULL, 0, false);
+ afs_extract_discard(call, 0);
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;

@@ -455,16 +452,15 @@ static int afs_deliver_cb_probe_uuid(struct afs_call *call)

switch (call->unmarshall) {
case 0:
- call->offset = 0;
call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
if (!call->buffer)
return -ENOMEM;
+ afs_extract_to_buf(call, 11 * sizeof(__be32));
call->unmarshall++;

case 1:
_debug("extract UUID");
- ret = afs_extract_data(call, call->buffer,
- 11 * sizeof(__be32), false);
+ ret = afs_extract_data(call, false);
switch (ret) {
case 0: break;
case -EAGAIN: return 0;
@@ -487,7 +483,6 @@ static int afs_deliver_cb_probe_uuid(struct afs_call *call)
for (loop = 0; loop < 6; loop++)
r->node[loop] = ntohl(b[loop + 5]);

- call->offset = 0;
call->unmarshall++;

case 2:
@@ -572,7 +567,8 @@ static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)

_enter("");

- ret = afs_extract_data(call, NULL, 0, false);
+ afs_extract_discard(call, 0);
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;

diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index d9a5815945dc..fe2e9e39b388 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -20,12 +20,6 @@

static const struct afs_fid afs_zero_fid;

-/*
- * We need somewhere to discard into in case the server helpfully returns more
- * than we asked for in FS.FetchData{,64}.
- */
-static u8 afs_discard_buffer[64];
-
static inline void afs_use_fs_server(struct afs_call *call, struct afs_cb_interest *cbi)
{
call->cbi = afs_get_cb_interest(cbi);
@@ -469,114 +463,93 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
struct afs_read *req = call->reply[2];
const __be32 *bp;
unsigned int size;
- void *buffer;
int ret;

- _enter("{%u,%zu/%u;%llu/%llu}",
- call->unmarshall, call->offset, call->count,
- req->remain, req->actual_len);
+ _enter("{%u,%zu/%llu}",
+ call->unmarshall, iov_iter_count(&call->iter), req->actual_len);

switch (call->unmarshall) {
case 0:
req->actual_len = 0;
- call->offset = 0;
+ req->index = 0;
+ req->offset = req->pos & (PAGE_SIZE - 1);
call->unmarshall++;
- if (call->operation_ID != FSFETCHDATA64) {
- call->unmarshall++;
- goto no_msw;
+ if (call->operation_ID == FSFETCHDATA64) {
+ afs_extract_to_tmp64(call);
+ } else {
+ call->tmp_u = htonl(0);
+ afs_extract_to_tmp(call);
}

- /* extract the upper part of the returned data length of an
- * FSFETCHDATA64 op (which should always be 0 using this
- * client) */
- case 1:
- _debug("extract data length (MSW)");
- ret = afs_extract_data(call, &call->tmp, 4, true);
- if (ret < 0)
- return ret;
-
- req->actual_len = ntohl(call->tmp);
- req->actual_len <<= 32;
- call->offset = 0;
- call->unmarshall++;
-
- no_msw:
/* extract the returned data length */
- case 2:
+ case 1:
_debug("extract data length");
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

- req->actual_len |= ntohl(call->tmp);
+ req->actual_len = be64_to_cpu(call->tmp64);
_debug("DATA length: %llu", req->actual_len);
-
- req->remain = req->actual_len;
- call->offset = req->pos & (PAGE_SIZE - 1);
- req->index = 0;
- if (req->actual_len == 0)
+ req->remain = min(req->len, req->actual_len);
+ if (req->remain == 0)
goto no_more_data;
+
call->unmarshall++;

begin_page:
ASSERTCMP(req->index, <, req->nr_pages);
- if (req->remain > PAGE_SIZE - call->offset)
- size = PAGE_SIZE - call->offset;
+ if (req->remain > PAGE_SIZE - req->offset)
+ size = PAGE_SIZE - req->offset;
else
size = req->remain;
- call->count = call->offset + size;
- ASSERTCMP(call->count, <=, PAGE_SIZE);
- req->remain -= size;
+ call->bvec[0].bv_len = size;
+ call->bvec[0].bv_offset = req->offset;
+ call->bvec[0].bv_page = req->pages[req->index];
+ iov_iter_bvec(&call->iter, READ, call->bvec, 1, size);
+ ASSERTCMP(size, <=, PAGE_SIZE);

/* extract the returned data */
- case 3:
- _debug("extract data %llu/%llu %zu/%u",
- req->remain, req->actual_len, call->offset, call->count);
+ case 2:
+ _debug("extract data %zu/%llu",
+ iov_iter_count(&call->iter), req->remain);

- buffer = kmap(req->pages[req->index]);
- ret = afs_extract_data(call, buffer, call->count, true);
- kunmap(req->pages[req->index]);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
- if (call->offset == PAGE_SIZE) {
+ req->remain -= call->bvec[0].bv_len;
+ req->offset += call->bvec[0].bv_len;
+ ASSERTCMP(req->offset, <=, PAGE_SIZE);
+ if (req->offset == PAGE_SIZE) {
+ req->offset = 0;
if (req->page_done)
req->page_done(call, req);
req->index++;
- if (req->remain > 0) {
- call->offset = 0;
- if (req->index >= req->nr_pages) {
- call->unmarshall = 4;
- goto begin_discard;
- }
+ if (req->remain > 0)
goto begin_page;
- }
}
- goto no_more_data;
+
+ ASSERTCMP(req->remain, ==, 0);
+ if (req->actual_len <= req->len)
+ goto no_more_data;

/* Discard any excess data the server gave us */
- begin_discard:
- case 4:
- size = min_t(loff_t, sizeof(afs_discard_buffer), req->remain);
- call->count = size;
- _debug("extract discard %llu/%llu %zu/%u",
- req->remain, req->actual_len, call->offset, call->count);
-
- call->offset = 0;
- ret = afs_extract_data(call, afs_discard_buffer, call->count, true);
- req->remain -= call->offset;
+ iov_iter_discard(&call->iter, READ, req->actual_len - req->len);
+ call->unmarshall = 3;
+ case 3:
+ _debug("extract discard %zu/%llu",
+ iov_iter_count(&call->iter), req->actual_len - req->len);
+
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
- if (req->remain > 0)
- goto begin_discard;

no_more_data:
- call->offset = 0;
- call->unmarshall = 5;
+ call->unmarshall = 4;
+ afs_extract_to_buf(call, (21 + 3 + 6) * 4);

/* extract the metadata */
- case 5:
- ret = afs_extract_data(call, call->buffer,
- (21 + 3 + 6) * 4, false);
+ case 4:
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;

@@ -589,20 +562,19 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
if (call->reply[1])
xdr_decode_AFSVolSync(&bp, call->reply[1]);

- call->offset = 0;
call->unmarshall++;

- case 6:
+ case 5:
break;
}

for (; req->index < req->nr_pages; req->index++) {
- if (call->count < PAGE_SIZE)
+ if (req->offset < PAGE_SIZE)
zero_user_segment(req->pages[req->index],
- call->count, PAGE_SIZE);
+ req->offset, PAGE_SIZE);
if (req->page_done)
req->page_done(call, req);
- call->count = 0;
+ req->offset = 0;
}

_leave(" = 0 [done]");
@@ -1598,31 +1570,31 @@ static int afs_deliver_fs_get_volume_status(struct afs_call *call)
{
const __be32 *bp;
char *p;
+ u32 size;
int ret;

_enter("{%u}", call->unmarshall);

switch (call->unmarshall) {
case 0:
- call->offset = 0;
call->unmarshall++;
+ afs_extract_to_buf(call, 12 * 4);

/* extract the returned status record */
case 1:
_debug("extract status");
- ret = afs_extract_data(call, call->buffer,
- 12 * 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

bp = call->buffer;
xdr_decode_AFSFetchVolumeStatus(&bp, call->reply[1]);
- call->offset = 0;
call->unmarshall++;
+ afs_extract_to_tmp(call);

/* extract the volume name length */
case 2:
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -1631,46 +1603,26 @@ static int afs_deliver_fs_get_volume_status(struct afs_call *call)
if (call->count >= AFSNAMEMAX)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_volname_len);
- call->offset = 0;
+ size = (call->count + 3) & ~3; /* It's padded */
+ afs_extract_begin(call, call->reply[2], size);
call->unmarshall++;

/* extract the volume name */
case 3:
_debug("extract volname");
- if (call->count > 0) {
- ret = afs_extract_data(call, call->reply[2],
- call->count, true);
- if (ret < 0)
- return ret;
- }
+ ret = afs_extract_data(call, true);
+ if (ret < 0)
+ return ret;

p = call->reply[2];
p[call->count] = 0;
_debug("volname '%s'", p);
-
- call->offset = 0;
+ afs_extract_to_tmp(call);
call->unmarshall++;

- /* extract the volume name padding */
- if ((call->count & 3) == 0) {
- call->unmarshall++;
- goto no_volname_padding;
- }
- call->count = 4 - (call->count & 3);
-
- case 4:
- ret = afs_extract_data(call, call->buffer,
- call->count, true);
- if (ret < 0)
- return ret;
-
- call->offset = 0;
- call->unmarshall++;
- no_volname_padding:
-
/* extract the offline message length */
- case 5:
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ case 4:
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -1679,46 +1631,27 @@ static int afs_deliver_fs_get_volume_status(struct afs_call *call)
if (call->count >= AFSNAMEMAX)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_offline_msg_len);
- call->offset = 0;
+ size = (call->count + 3) & ~3; /* It's padded */
+ afs_extract_begin(call, call->reply[2], size);
call->unmarshall++;

/* extract the offline message */
- case 6:
+ case 5:
_debug("extract offline");
- if (call->count > 0) {
- ret = afs_extract_data(call, call->reply[2],
- call->count, true);
- if (ret < 0)
- return ret;
- }
+ ret = afs_extract_data(call, true);
+ if (ret < 0)
+ return ret;

p = call->reply[2];
p[call->count] = 0;
_debug("offline '%s'", p);

- call->offset = 0;
+ afs_extract_to_tmp(call);
call->unmarshall++;

- /* extract the offline message padding */
- if ((call->count & 3) == 0) {
- call->unmarshall++;
- goto no_offline_padding;
- }
- call->count = 4 - (call->count & 3);
-
- case 7:
- ret = afs_extract_data(call, call->buffer,
- call->count, true);
- if (ret < 0)
- return ret;
-
- call->offset = 0;
- call->unmarshall++;
- no_offline_padding:
-
/* extract the message of the day length */
- case 8:
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ case 6:
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -1727,38 +1660,24 @@ static int afs_deliver_fs_get_volume_status(struct afs_call *call)
if (call->count >= AFSNAMEMAX)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_motd_len);
- call->offset = 0;
+ size = (call->count + 3) & ~3; /* It's padded */
+ afs_extract_begin(call, call->reply[2], size);
call->unmarshall++;

/* extract the message of the day */
- case 9:
+ case 7:
_debug("extract motd");
- if (call->count > 0) {
- ret = afs_extract_data(call, call->reply[2],
- call->count, true);
- if (ret < 0)
- return ret;
- }
+ ret = afs_extract_data(call, false);
+ if (ret < 0)
+ return ret;

p = call->reply[2];
p[call->count] = 0;
_debug("motd '%s'", p);

- call->offset = 0;
call->unmarshall++;

- /* extract the message of the day padding */
- call->count = (4 - (call->count & 3)) & 3;
-
- case 10:
- ret = afs_extract_data(call, call->buffer,
- call->count, false);
- if (ret < 0)
- return ret;
-
- call->offset = 0;
- call->unmarshall++;
- case 11:
+ case 8:
break;
}

@@ -2024,19 +1943,16 @@ static int afs_deliver_fs_get_capabilities(struct afs_call *call)
u32 count;
int ret;

- _enter("{%u,%zu/%u}", call->unmarshall, call->offset, call->count);
+ _enter("{%u,%zu}", call->unmarshall, iov_iter_count(&call->iter));

-again:
switch (call->unmarshall) {
case 0:
- call->offset = 0;
+ afs_extract_to_tmp(call);
call->unmarshall++;

/* Extract the capabilities word count */
case 1:
- ret = afs_extract_data(call, &call->tmp,
- 1 * sizeof(__be32),
- true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -2044,24 +1960,17 @@ static int afs_deliver_fs_get_capabilities(struct afs_call *call)

call->count = count;
call->count2 = count;
- call->offset = 0;
+ iov_iter_discard(&call->iter, READ, count * sizeof(__be32));
call->unmarshall++;

/* Extract capabilities words */
case 2:
- count = min(call->count, 16U);
- ret = afs_extract_data(call, call->buffer,
- count * sizeof(__be32),
- call->count > 16);
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;

/* TODO: Examine capabilities */

- call->count -= count;
- if (call->count > 0)
- goto again;
- call->offset = 0;
call->unmarshall++;
break;
}
@@ -2215,13 +2124,13 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)

switch (call->unmarshall) {
case 0:
- call->offset = 0;
+ afs_extract_to_tmp(call);
call->unmarshall++;

/* Extract the file status count and array in two steps */
case 1:
_debug("extract status count");
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -2234,11 +2143,11 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
call->count = 0;
call->unmarshall++;
more_counts:
- call->offset = 0;
+ afs_extract_to_buf(call, 21 * sizeof(__be32));

case 2:
_debug("extract status array %u", call->count);
- ret = afs_extract_data(call, call->buffer, 21 * 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -2256,12 +2165,12 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)

call->count = 0;
call->unmarshall++;
- call->offset = 0;
+ afs_extract_to_tmp(call);

/* Extract the callback count and array in two steps */
case 3:
_debug("extract CB count");
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -2273,11 +2182,11 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
call->count = 0;
call->unmarshall++;
more_cbs:
- call->offset = 0;
+ afs_extract_to_buf(call, 3 * sizeof(__be32));

case 4:
_debug("extract CB array");
- ret = afs_extract_data(call, call->buffer, 3 * 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -2294,11 +2203,11 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
if (call->count < call->count2)
goto more_cbs;

- call->offset = 0;
+ afs_extract_to_buf(call, 6 * sizeof(__be32));
call->unmarshall++;

case 5:
- ret = afs_extract_data(call, call->buffer, 6 * 4, false);
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;

@@ -2306,7 +2215,6 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
if (call->reply[3])
xdr_decode_AFSVolSync(&bp, call->reply[3]);

- call->offset = 0;
call->unmarshall++;

case 6:
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 73770a2a2311..36e9cc74ac11 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -98,11 +98,16 @@ struct afs_call {
struct afs_cb_interest *cbi; /* Callback interest for server used */
void *request; /* request data (first part) */
struct address_space *mapping; /* Pages being written from */
+ struct iov_iter iter; /* Buffer iterator */
+ struct iov_iter *_iter; /* Iterator currently in use */
+ union { /* Convenience for ->iter */
+ struct kvec kvec[1];
+ struct bio_vec bvec[1];
+ };
void *buffer; /* reply receive buffer */
void *reply[4]; /* Where to put the reply */
pgoff_t first; /* first page in mapping to deal with */
pgoff_t last; /* last page in mapping to deal with */
- size_t offset; /* offset into received data store */
atomic_t usage;
enum afs_call_state state;
spinlock_t state_lock;
@@ -127,7 +132,13 @@ struct afs_call {
unsigned int debug_id; /* Trace ID */
u32 operation_ID; /* operation ID for an incoming call */
u32 count; /* count for use in unmarshalling */
- __be32 tmp; /* place to extract temporary data */
+ union { /* place to extract temporary data */
+ struct {
+ __be32 tmp_u;
+ __be32 tmp;
+ } __attribute__((packed));
+ __be64 tmp64;
+ };
afs_dataversion_t expected_version; /* Updated version expected from store */
afs_dataversion_t expected_version_2; /* 2nd updated version expected from store */
};
@@ -185,6 +196,7 @@ struct afs_read {
refcount_t usage;
unsigned int index; /* Which page we're reading into */
unsigned int nr_pages;
+ unsigned int offset; /* offset into current page */
void (*page_done)(struct afs_call *, struct afs_read *);
struct page **pages;
struct page *array[];
@@ -550,6 +562,15 @@ struct afs_vnode {
afs_callback_type_t cb_type; /* type of callback */
};

+static inline struct fscache_cookie *afs_vnode_cache(struct afs_vnode *vnode)
+{
+#ifdef CONFIG_AFS_FSCACHE
+ return vnode->cache;
+#else
+ return NULL;
+#endif
+}
+
/*
* cached security record for one user's attempt to access a vnode
*/
@@ -930,12 +951,39 @@ extern struct afs_call *afs_alloc_flat_call(struct afs_net *,
extern void afs_flat_call_destructor(struct afs_call *);
extern void afs_send_empty_reply(struct afs_call *);
extern void afs_send_simple_reply(struct afs_call *, const void *, size_t);
-extern int afs_extract_data(struct afs_call *, void *, size_t, bool);
+extern int afs_extract_data(struct afs_call *, bool);
extern int afs_protocol_error(struct afs_call *, int, enum afs_eproto_cause);

+static inline void afs_extract_begin(struct afs_call *call, void *buf, size_t size)
+{
+ call->kvec[0].iov_base = buf;
+ call->kvec[0].iov_len = size;
+ iov_iter_kvec(&call->iter, READ, call->kvec, 1, size);
+}
+
+static inline void afs_extract_to_tmp(struct afs_call *call)
+{
+ afs_extract_begin(call, &call->tmp, sizeof(call->tmp));
+}
+
+static inline void afs_extract_to_tmp64(struct afs_call *call)
+{
+ afs_extract_begin(call, &call->tmp64, sizeof(call->tmp64));
+}
+
+static inline void afs_extract_discard(struct afs_call *call, size_t size)
+{
+ iov_iter_discard(&call->iter, READ, size);
+}
+
+static inline void afs_extract_to_buf(struct afs_call *call, size_t size)
+{
+ afs_extract_begin(call, call->buffer, size);
+}
+
static inline int afs_transfer_reply(struct afs_call *call)
{
- return afs_extract_data(call, call->buffer, call->reply_max, false);
+ return afs_extract_data(call, false);
}

static inline bool afs_check_call_state(struct afs_call *call,
diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 9757c2d953f1..a3904a8315de 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -143,6 +143,7 @@ static struct afs_call *afs_alloc_call(struct afs_net *net,
INIT_WORK(&call->async_work, afs_process_async_call);
init_waitqueue_head(&call->waitq);
spin_lock_init(&call->state_lock);
+ call->_iter = &call->iter;

o = atomic_inc_return(&net->nr_outstanding_calls);
trace_afs_call(call, afs_call_trace_alloc, 1, o,
@@ -233,6 +234,7 @@ struct afs_call *afs_alloc_flat_call(struct afs_net *net,
goto nomem_free;
}

+ afs_extract_to_buf(call, call->reply_max);
call->operation_ID = type->op;
init_waitqueue_head(&call->waitq);
return call;
@@ -465,14 +467,12 @@ static void afs_deliver_to_call(struct afs_call *call)
state == AFS_CALL_SV_AWAIT_ACK
) {
if (state == AFS_CALL_SV_AWAIT_ACK) {
- struct iov_iter iter;
-
- iov_iter_kvec(&iter, READ, NULL, 0, 0);
+ iov_iter_kvec(&call->iter, READ, NULL, 0, 0);
ret = rxrpc_kernel_recv_data(call->net->socket,
- call->rxcall, &iter, false,
- &remote_abort,
+ call->rxcall, &call->iter,
+ false, &remote_abort,
&call->service_id);
- trace_afs_recv_data(call, 0, 0, false, ret);
+ trace_afs_receive_data(call, &call->iter, false, ret);

if (ret == -EINPROGRESS || ret == -EAGAIN)
return;
@@ -516,7 +516,7 @@ static void afs_deliver_to_call(struct afs_call *call)
if (state != AFS_CALL_CL_AWAIT_REPLY)
abort_code = RXGEN_SS_UNMARSHAL;
rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
- abort_code, -EBADMSG, "KUM");
+ abort_code, ret, "KUM");
goto local_abort;
}
}
@@ -727,6 +727,7 @@ void afs_charge_preallocation(struct work_struct *work)
call->async = true;
call->state = AFS_CALL_SV_AWAIT_OP_ID;
init_waitqueue_head(&call->waitq);
+ afs_extract_to_tmp(call);
}

if (rxrpc_kernel_charge_accept(net->socket,
@@ -772,18 +773,15 @@ static int afs_deliver_cm_op_id(struct afs_call *call)
{
int ret;

- _enter("{%zu}", call->offset);
-
- ASSERTCMP(call->offset, <, 4);
+ _enter("{%zu}", iov_iter_count(call->_iter));

/* the operation ID forms the first four bytes of the request data */
- ret = afs_extract_data(call, &call->tmp, 4, true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

call->operation_ID = ntohl(call->tmp);
afs_set_call_state(call, AFS_CALL_SV_AWAIT_OP_ID, AFS_CALL_SV_AWAIT_REQUEST);
- call->offset = 0;

/* ask the cache manager to route the call (it'll change the call type
* if successful) */
@@ -887,30 +885,19 @@ void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
/*
* Extract a piece of data from the received data socket buffers.
*/
-int afs_extract_data(struct afs_call *call, void *buf, size_t count,
- bool want_more)
+int afs_extract_data(struct afs_call *call, bool want_more)
{
struct afs_net *net = call->net;
- struct iov_iter iter;
- struct kvec iov;
+ struct iov_iter *iter = call->_iter;
enum afs_call_state state;
u32 remote_abort = 0;
int ret;

- _enter("{%s,%zu},,%zu,%d",
- call->type->name, call->offset, count, want_more);
-
- ASSERTCMP(call->offset, <=, count);
-
- iov.iov_base = buf + call->offset;
- iov.iov_len = count - call->offset;
- iov_iter_kvec(&iter, READ, &iov, 1, count - call->offset);
+ _enter("{%s,%zu},%d", call->type->name, iov_iter_count(iter), want_more);

- ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, &iter,
+ ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter,
want_more, &remote_abort,
&call->service_id);
- call->offset += (count - call->offset) - iov_iter_count(&iter);
- trace_afs_recv_data(call, count, call->offset, want_more, ret);
if (ret == 0 || ret == -EAGAIN)
return ret;

diff --git a/fs/afs/vlclient.c b/fs/afs/vlclient.c
index d0f95c4ab05e..e18c51742daa 100644
--- a/fs/afs/vlclient.c
+++ b/fs/afs/vlclient.c
@@ -187,19 +187,18 @@ static int afs_deliver_vl_get_addrs_u(struct afs_call *call)
u32 uniquifier, nentries, count;
int i, ret;

- _enter("{%u,%zu/%u}", call->unmarshall, call->offset, call->count);
+ _enter("{%u,%zu/%u}",
+ call->unmarshall, iov_iter_count(call->_iter), call->count);

-again:
switch (call->unmarshall) {
case 0:
- call->offset = 0;
+ afs_extract_to_buf(call,
+ sizeof(struct afs_uuid__xdr) + 3 * sizeof(__be32));
call->unmarshall++;

/* Extract the returned uuid, uniquifier, nentries and blkaddrs size */
case 1:
- ret = afs_extract_data(call, call->buffer,
- sizeof(struct afs_uuid__xdr) + 3 * sizeof(__be32),
- true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -216,28 +215,28 @@ static int afs_deliver_vl_get_addrs_u(struct afs_call *call)
call->reply[0] = alist;
call->count = count;
call->count2 = nentries;
- call->offset = 0;
call->unmarshall++;

+ more_entries:
+ count = min(call->count, 4U);
+ afs_extract_to_buf(call, count * sizeof(__be32));
+
/* Extract entries */
case 2:
- count = min(call->count, 4U);
- ret = afs_extract_data(call, call->buffer,
- count * sizeof(__be32),
- call->count > 4);
+ ret = afs_extract_data(call, call->count > 4);
if (ret < 0)
return ret;

alist = call->reply[0];
bp = call->buffer;
+ count = min(call->count, 4U);
for (i = 0; i < count; i++)
if (alist->nr_addrs < call->count2)
afs_merge_fs_addr4(alist, *bp++, AFS_FS_PORT);

call->count -= count;
if (call->count > 0)
- goto again;
- call->offset = 0;
+ goto more_entries;
call->unmarshall++;
break;
}
@@ -318,44 +317,35 @@ static int afs_deliver_vl_get_capabilities(struct afs_call *call)
u32 count;
int ret;

- _enter("{%u,%zu/%u}", call->unmarshall, call->offset, call->count);
+ _enter("{%u,%zu/%u}",
+ call->unmarshall, iov_iter_count(call->_iter), call->count);

-again:
switch (call->unmarshall) {
case 0:
- call->offset = 0;
+ afs_extract_to_tmp(call);
call->unmarshall++;

/* Extract the capabilities word count */
case 1:
- ret = afs_extract_data(call, &call->tmp,
- 1 * sizeof(__be32),
- true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

count = ntohl(call->tmp);
-
call->count = count;
call->count2 = count;
- call->offset = 0;
+
call->unmarshall++;
+ afs_extract_discard(call, count * sizeof(__be32));

/* Extract capabilities words */
case 2:
- count = min(call->count, 16U);
- ret = afs_extract_data(call, call->buffer,
- count * sizeof(__be32),
- call->count > 16);
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;

/* TODO: Examine capabilities */

- call->count -= count;
- if (call->count > 0)
- goto again;
- call->offset = 0;
call->unmarshall++;
break;
}
@@ -426,22 +416,19 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
u32 uniquifier, size;
int ret;

- _enter("{%u,%zu/%u,%u}", call->unmarshall, call->offset, call->count, call->count2);
+ _enter("{%u,%zu,%u}",
+ call->unmarshall, iov_iter_count(call->_iter), call->count2);

-again:
switch (call->unmarshall) {
case 0:
- call->offset = 0;
+ afs_extract_to_buf(call, sizeof(uuid_t) + 3 * sizeof(__be32));
call->unmarshall = 1;

/* Extract the returned uuid, uniquifier, fsEndpoints count and
* either the first fsEndpoint type or the volEndpoints
* count if there are no fsEndpoints. */
case 1:
- ret = afs_extract_data(call, call->buffer,
- sizeof(uuid_t) +
- 3 * sizeof(__be32),
- true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -459,15 +446,11 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
return -ENOMEM;
alist->version = uniquifier;
call->reply[0] = alist;
- call->offset = 0;

if (call->count == 0)
goto extract_volendpoints;

- call->unmarshall = 2;
-
- /* Extract fsEndpoints[] entries */
- case 2:
+ next_fsendpoint:
switch (call->count2) {
case YFS_ENDPOINT_IPV4:
size = sizeof(__be32) * (1 + 1 + 1);
@@ -481,7 +464,12 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
}

size += sizeof(__be32);
- ret = afs_extract_data(call, call->buffer, size, true);
+ afs_extract_to_buf(call, size);
+ call->unmarshall = 2;
+
+ /* Extract fsEndpoints[] entries */
+ case 2:
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -512,10 +500,9 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
*/
call->count2 = ntohl(*bp++);

- call->offset = 0;
call->count--;
if (call->count > 0)
- goto again;
+ goto next_fsendpoint;

extract_volendpoints:
/* Extract the list of volEndpoints. */
@@ -526,6 +513,7 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_vlendpt_type);

+ afs_extract_to_buf(call, 1 * sizeof(__be32));
call->unmarshall = 3;

/* Extract the type of volEndpoints[0]. Normally we would
@@ -533,17 +521,14 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
* data of the current one, but this is the first...
*/
case 3:
- ret = afs_extract_data(call, call->buffer, sizeof(__be32), true);
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

bp = call->buffer;
- call->count2 = ntohl(*bp++);
- call->offset = 0;
- call->unmarshall = 4;

- /* Extract volEndpoints[] entries */
- case 4:
+ next_volendpoint:
+ call->count2 = ntohl(*bp++);
switch (call->count2) {
case YFS_ENDPOINT_IPV4:
size = sizeof(__be32) * (1 + 1 + 1);
@@ -557,8 +542,13 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
}

if (call->count > 1)
- size += sizeof(__be32);
- ret = afs_extract_data(call, call->buffer, size, true);
+ size += sizeof(__be32); /* Get next type too */
+ afs_extract_to_buf(call, size);
+ call->unmarshall = 4;
+
+ /* Extract volEndpoints[] entries */
+ case 4:
+ ret = afs_extract_data(call, true);
if (ret < 0)
return ret;

@@ -584,19 +574,17 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
/* Got either the type of the next entry or the count of
* volEndpoints if no more fsEndpoints.
*/
- call->offset = 0;
call->count--;
- if (call->count > 0) {
- call->count2 = ntohl(*bp++);
- goto again;
- }
+ if (call->count > 0)
+ goto next_volendpoint;

end:
+ afs_extract_discard(call, 0);
call->unmarshall = 5;

/* Done */
case 5:
- ret = afs_extract_data(call, call->buffer, 0, false);
+ ret = afs_extract_data(call, false);
if (ret < 0)
return ret;
call->unmarshall = 6;
diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h
index 5c60ade2c7d8..5e0f8dcede26 100644
--- a/include/trace/events/afs.h
+++ b/include/trace/events/afs.h
@@ -207,17 +207,16 @@ afs_edit_dir_reasons;
#define EM(a, b) { a, b },
#define E_(a, b) { a, b }

-TRACE_EVENT(afs_recv_data,
- TP_PROTO(struct afs_call *call, unsigned count, unsigned offset,
+TRACE_EVENT(afs_receive_data,
+ TP_PROTO(struct afs_call *call, struct iov_iter *iter,
bool want_more, int ret),

- TP_ARGS(call, count, offset, want_more, ret),
+ TP_ARGS(call, iter, want_more, ret),

TP_STRUCT__entry(
+ __field(loff_t, remain )
__field(unsigned int, call )
__field(enum afs_call_state, state )
- __field(unsigned int, count )
- __field(unsigned int, offset )
__field(unsigned short, unmarshall )
__field(bool, want_more )
__field(int, ret )
@@ -227,17 +226,18 @@ TRACE_EVENT(afs_recv_data,
__entry->call = call->debug_id;
__entry->state = call->state;
__entry->unmarshall = call->unmarshall;
- __entry->count = count;
- __entry->offset = offset;
+ __entry->remain = iov_iter_count(iter);
__entry->want_more = want_more;
__entry->ret = ret;
),

- TP_printk("c=%08x s=%u u=%u %u/%u wm=%u ret=%d",
+ TP_printk("c=%08x r=%llu u=%u w=%u s=%u ret=%d",
__entry->call,
- __entry->state, __entry->unmarshall,
- __entry->offset, __entry->count,
- __entry->want_more, __entry->ret)
+ __entry->remain,
+ __entry->unmarshall,
+ __entry->want_more,
+ __entry->state,
+ __entry->ret)
);

TRACE_EVENT(afs_notify_call,