[PATCH 1/2] VMCI: Remove non-blocking/pinned queuepair support
From: Andy King
Date: Fri Aug 23 2013 - 12:22:29 EST
We added this for a special case that doesn't exist on Linux. Remove
the non-blocking/pinned queuepair code and simplify the driver in
preparation for adding virtual IOMMU support.
Acked-by: Aditya Sarwade <asarwade@xxxxxxxxxx>
Signed-off-by: Andy King <acking@xxxxxxxxxx>
---
drivers/misc/vmw_vmci/vmci_queue_pair.c | 149 +++++--------------------------
drivers/misc/vmw_vmci/vmci_queue_pair.h | 18 ----
2 files changed, 22 insertions(+), 145 deletions(-)
diff --git a/drivers/misc/vmw_vmci/vmci_queue_pair.c b/drivers/misc/vmw_vmci/vmci_queue_pair.c
index 8ff2e5e..8698e0c 100644
--- a/drivers/misc/vmw_vmci/vmci_queue_pair.c
+++ b/drivers/misc/vmw_vmci/vmci_queue_pair.c
@@ -148,12 +148,10 @@ typedef int vmci_memcpy_from_queue_func(void *dest, size_t dest_offset,
struct vmci_queue_kern_if {
struct page **page;
struct page **header_page;
- void *va;
struct mutex __mutex; /* Protects the queue. */
struct mutex *mutex; /* Shared by producer and consumer queues. */
bool host;
size_t num_pages;
- bool mapped;
};
/*
@@ -267,11 +265,6 @@ static void qp_free_queue(void *q, u64 size)
if (queue) {
u64 i = DIV_ROUND_UP(size, PAGE_SIZE);
- if (queue->kernel_if->mapped) {
- vunmap(queue->kernel_if->va);
- queue->kernel_if->va = NULL;
- }
-
while (i)
__free_page(queue->kernel_if->page[--i]);
@@ -311,8 +304,6 @@ static void *qp_alloc_queue(u64 size, u32 flags)
queue->kernel_if->header_page = NULL; /* Unused in guest. */
queue->kernel_if->page = (struct page **)(queue->kernel_if + 1);
queue->kernel_if->host = false;
- queue->kernel_if->va = NULL;
- queue->kernel_if->mapped = false;
for (i = 0; i < num_data_pages; i++) {
queue->kernel_if->page[i] = alloc_pages(GFP_KERNEL, 0);
@@ -320,16 +311,6 @@ static void *qp_alloc_queue(u64 size, u32 flags)
goto fail;
}
- if (vmci_qp_pinned(flags)) {
- queue->kernel_if->va =
- vmap(queue->kernel_if->page, num_data_pages, VM_MAP,
- PAGE_KERNEL);
- if (!queue->kernel_if->va)
- goto fail;
-
- queue->kernel_if->mapped = true;
- }
-
return (void *)queue;
fail:
@@ -359,11 +340,7 @@ static int __qp_memcpy_to_queue(struct vmci_queue *queue,
void *va;
size_t to_copy;
- if (!kernel_if->mapped)
- va = kmap(kernel_if->page[page_index]);
- else
- va = (void *)((u8 *)kernel_if->va +
- (page_index * PAGE_SIZE));
+ va = kmap(kernel_if->page[page_index]);
if (size - bytes_copied > PAGE_SIZE - page_offset)
/* Enough payload to fill up from this page. */
@@ -388,8 +365,7 @@ static int __qp_memcpy_to_queue(struct vmci_queue *queue,
}
bytes_copied += to_copy;
- if (!kernel_if->mapped)
- kunmap(kernel_if->page[page_index]);
+ kunmap(kernel_if->page[page_index]);
}
return VMCI_SUCCESS;
@@ -417,11 +393,7 @@ static int __qp_memcpy_from_queue(void *dest,
void *va;
size_t to_copy;
- if (!kernel_if->mapped)
- va = kmap(kernel_if->page[page_index]);
- else
- va = (void *)((u8 *)kernel_if->va +
- (page_index * PAGE_SIZE));
+ va = kmap(kernel_if->page[page_index]);
if (size - bytes_copied > PAGE_SIZE - page_offset)
/* Enough payload to fill up this page. */
@@ -446,8 +418,7 @@ static int __qp_memcpy_from_queue(void *dest,
}
bytes_copied += to_copy;
- if (!kernel_if->mapped)
- kunmap(kernel_if->page[page_index]);
+ kunmap(kernel_if->page[page_index]);
}
return VMCI_SUCCESS;
@@ -634,8 +605,6 @@ static struct vmci_queue *qp_host_alloc_queue(u64 size)
queue->kernel_if->header_page =
(struct page **)((u8 *)queue + queue_size);
queue->kernel_if->page = &queue->kernel_if->header_page[1];
- queue->kernel_if->va = NULL;
- queue->kernel_if->mapped = false;
}
return queue;
@@ -1720,21 +1689,6 @@ static int qp_broker_attach(struct qp_broker_entry *entry,
if (result < VMCI_SUCCESS)
return result;
- /*
- * Preemptively load in the headers if non-blocking to
- * prevent blocking later.
- */
- if (entry->qp.flags & VMCI_QPFLAG_NONBLOCK) {
- result = qp_host_map_queues(entry->produce_q,
- entry->consume_q);
- if (result < VMCI_SUCCESS) {
- qp_host_unregister_user_memory(
- entry->produce_q,
- entry->consume_q);
- return result;
- }
- }
-
entry->state = VMCIQPB_ATTACHED_MEM;
} else {
entry->state = VMCIQPB_ATTACHED_NO_MEM;
@@ -1749,24 +1703,6 @@ static int qp_broker_attach(struct qp_broker_entry *entry,
return VMCI_ERROR_UNAVAILABLE;
} else {
- /*
- * For non-blocking queue pairs, we cannot rely on
- * enqueue/dequeue to map in the pages on the
- * host-side, since it may block, so we make an
- * attempt here.
- */
-
- if (flags & VMCI_QPFLAG_NONBLOCK) {
- result =
- qp_host_map_queues(entry->produce_q,
- entry->consume_q);
- if (result < VMCI_SUCCESS)
- return result;
-
- entry->qp.flags |= flags &
- (VMCI_QPFLAG_NONBLOCK | VMCI_QPFLAG_PINNED);
- }
-
/* The host side has successfully attached to a queue pair. */
entry->state = VMCIQPB_ATTACHED_MEM;
}
@@ -2543,24 +2479,19 @@ void vmci_qp_guest_endpoints_exit(void)
* Since non-blocking isn't yet implemented on the host personality we
* have no reason to acquire a spin lock. So to avoid the use of an
* unnecessary lock only acquire the mutex if we can block.
- * Note: It is assumed that QPFLAG_PINNED implies QPFLAG_NONBLOCK. Therefore
- * we can use the same locking function for access to both the queue
- * and the queue headers as it is the same logic. Assert this behvior.
*/
static void qp_lock(const struct vmci_qp *qpair)
{
- if (vmci_can_block(qpair->flags))
- qp_acquire_queue_mutex(qpair->produce_q);
+ qp_acquire_queue_mutex(qpair->produce_q);
}
/*
* Helper routine that unlocks the queue pair after calling
- * qp_lock. Respects non-blocking and pinning flags.
+ * qp_lock.
*/
static void qp_unlock(const struct vmci_qp *qpair)
{
- if (vmci_can_block(qpair->flags))
- qp_release_queue_mutex(qpair->produce_q);
+ qp_release_queue_mutex(qpair->produce_q);
}
/*
@@ -2568,17 +2499,12 @@ static void qp_unlock(const struct vmci_qp *qpair)
* currently not mapped, it will be attempted to do so.
*/
static int qp_map_queue_headers(struct vmci_queue *produce_q,
- struct vmci_queue *consume_q,
- bool can_block)
+ struct vmci_queue *consume_q)
{
int result;
if (NULL == produce_q->q_header || NULL == consume_q->q_header) {
- if (can_block)
- result = qp_host_map_queues(produce_q, consume_q);
- else
- result = VMCI_ERROR_QUEUEPAIR_NOT_READY;
-
+ result = qp_host_map_queues(produce_q, consume_q);
if (result < VMCI_SUCCESS)
return (produce_q->saved_header &&
consume_q->saved_header) ?
@@ -2601,8 +2527,7 @@ static int qp_get_queue_headers(const struct vmci_qp *qpair,
{
int result;
- result = qp_map_queue_headers(qpair->produce_q, qpair->consume_q,
- vmci_can_block(qpair->flags));
+ result = qp_map_queue_headers(qpair->produce_q, qpair->consume_q);
if (result == VMCI_SUCCESS) {
*produce_q_header = qpair->produce_q->q_header;
*consume_q_header = qpair->consume_q->q_header;
@@ -2645,9 +2570,6 @@ static bool qp_wait_for_ready_queue(struct vmci_qp *qpair)
{
unsigned int generation;
- if (qpair->flags & VMCI_QPFLAG_NONBLOCK)
- return false;
-
qpair->blocked++;
generation = qpair->generation;
qp_unlock(qpair);
@@ -2674,15 +2596,14 @@ static ssize_t qp_enqueue_locked(struct vmci_queue *produce_q,
const u64 produce_q_size,
const void *buf,
size_t buf_size,
- vmci_memcpy_to_queue_func memcpy_to_queue,
- bool can_block)
+ vmci_memcpy_to_queue_func memcpy_to_queue)
{
s64 free_space;
u64 tail;
size_t written;
ssize_t result;
- result = qp_map_queue_headers(produce_q, consume_q, can_block);
+ result = qp_map_queue_headers(produce_q, consume_q);
if (unlikely(result != VMCI_SUCCESS))
return result;
@@ -2737,15 +2658,14 @@ static ssize_t qp_dequeue_locked(struct vmci_queue *produce_q,
void *buf,
size_t buf_size,
vmci_memcpy_from_queue_func memcpy_from_queue,
- bool update_consumer,
- bool can_block)
+ bool update_consumer)
{
s64 buf_ready;
u64 head;
size_t read;
ssize_t result;
- result = qp_map_queue_headers(produce_q, consume_q, can_block);
+ result = qp_map_queue_headers(produce_q, consume_q);
if (unlikely(result != VMCI_SUCCESS))
return result;
@@ -2842,32 +2762,11 @@ int vmci_qpair_alloc(struct vmci_qp **qpair,
route = vmci_guest_code_active() ?
VMCI_ROUTE_AS_GUEST : VMCI_ROUTE_AS_HOST;
- /* If NONBLOCK or PINNED is set, we better be the guest personality. */
- if ((!vmci_can_block(flags) || vmci_qp_pinned(flags)) &&
- VMCI_ROUTE_AS_GUEST != route) {
- pr_devel("Not guest personality w/ NONBLOCK OR PINNED set");
+ if (flags & (VMCI_QPFLAG_NONBLOCK | VMCI_QPFLAG_PINNED)) {
+ pr_devel("NONBLOCK OR PINNED set");
return VMCI_ERROR_INVALID_ARGS;
}
- /*
- * Limit the size of pinned QPs and check sanity.
- *
- * Pinned pages implies non-blocking mode. Mutexes aren't acquired
- * when the NONBLOCK flag is set in qpair code; and also should not be
- * acquired when the PINNED flagged is set. Since pinning pages
- * implies we want speed, it makes no sense not to have NONBLOCK
- * set if PINNED is set. Hence enforce this implication.
- */
- if (vmci_qp_pinned(flags)) {
- if (vmci_can_block(flags)) {
- pr_err("Attempted to enable pinning w/o non-blocking");
- return VMCI_ERROR_INVALID_ARGS;
- }
-
- if (produce_qsize + consume_qsize > VMCI_MAX_PINNED_QP_MEMORY)
- return VMCI_ERROR_NO_RESOURCES;
- }
-
my_qpair = kzalloc(sizeof(*my_qpair), GFP_KERNEL);
if (!my_qpair)
return VMCI_ERROR_NO_MEM;
@@ -3195,8 +3094,7 @@ ssize_t vmci_qpair_enqueue(struct vmci_qp *qpair,
qpair->consume_q,
qpair->produce_q_size,
buf, buf_size,
- qp_memcpy_to_queue,
- vmci_can_block(qpair->flags));
+ qp_memcpy_to_queue);
if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY &&
!qp_wait_for_ready_queue(qpair))
@@ -3237,8 +3135,7 @@ ssize_t vmci_qpair_dequeue(struct vmci_qp *qpair,
qpair->consume_q,
qpair->consume_q_size,
buf, buf_size,
- qp_memcpy_from_queue, true,
- vmci_can_block(qpair->flags));
+ qp_memcpy_from_queue, true);
if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY &&
!qp_wait_for_ready_queue(qpair))
@@ -3280,8 +3177,7 @@ ssize_t vmci_qpair_peek(struct vmci_qp *qpair,
qpair->consume_q,
qpair->consume_q_size,
buf, buf_size,
- qp_memcpy_from_queue, false,
- vmci_can_block(qpair->flags));
+ qp_memcpy_from_queue, false);
if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY &&
!qp_wait_for_ready_queue(qpair))
@@ -3323,8 +3219,7 @@ ssize_t vmci_qpair_enquev(struct vmci_qp *qpair,
qpair->consume_q,
qpair->produce_q_size,
iov, iov_size,
- qp_memcpy_to_queue_iov,
- vmci_can_block(qpair->flags));
+ qp_memcpy_to_queue_iov);
if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY &&
!qp_wait_for_ready_queue(qpair))
@@ -3367,7 +3262,7 @@ ssize_t vmci_qpair_dequev(struct vmci_qp *qpair,
qpair->consume_q_size,
iov, iov_size,
qp_memcpy_from_queue_iov,
- true, vmci_can_block(qpair->flags));
+ true);
if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY &&
!qp_wait_for_ready_queue(qpair))
@@ -3411,7 +3306,7 @@ ssize_t vmci_qpair_peekv(struct vmci_qp *qpair,
qpair->consume_q_size,
iov, iov_size,
qp_memcpy_from_queue_iov,
- false, vmci_can_block(qpair->flags));
+ false);
if (result == VMCI_ERROR_QUEUEPAIR_NOT_READY &&
!qp_wait_for_ready_queue(qpair))
diff --git a/drivers/misc/vmw_vmci/vmci_queue_pair.h b/drivers/misc/vmw_vmci/vmci_queue_pair.h
index 58c6959..ed177f0 100644
--- a/drivers/misc/vmw_vmci/vmci_queue_pair.h
+++ b/drivers/misc/vmw_vmci/vmci_queue_pair.h
@@ -146,24 +146,6 @@ VMCI_QP_PAGESTORE_IS_WELLFORMED(struct vmci_qp_page_store *page_store)
return page_store->len >= 2;
}
-/*
- * Helper function to check if the non-blocking flag
- * is set for a given queue pair.
- */
-static inline bool vmci_can_block(u32 flags)
-{
- return !(flags & VMCI_QPFLAG_NONBLOCK);
-}
-
-/*
- * Helper function to check if the queue pair is pinned
- * into memory.
- */
-static inline bool vmci_qp_pinned(u32 flags)
-{
- return flags & VMCI_QPFLAG_PINNED;
-}
-
void vmci_qp_broker_exit(void);
int vmci_qp_broker_alloc(struct vmci_handle handle, u32 peer,
u32 flags, u32 priv_flags,
--
1.7.4.1
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