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Diffstat (limited to 'include/linux/vmw_vmci_defs.h')
-rw-r--r--include/linux/vmw_vmci_defs.h51
1 files changed, 21 insertions, 30 deletions
diff --git a/include/linux/vmw_vmci_defs.h b/include/linux/vmw_vmci_defs.h
index 0c06178e4985..fefb5292403b 100644
--- a/include/linux/vmw_vmci_defs.h
+++ b/include/linux/vmw_vmci_defs.h
@@ -1,16 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
/*
* VMware VMCI Driver
*
* Copyright (C) 2012 VMware, Inc. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation version 2 and no later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * for more details.
*/
#ifndef _VMW_VMCI_DEF_H_
@@ -70,9 +62,18 @@ enum {
/*
* A single VMCI device has an upper limit of 128MB on the amount of
- * memory that can be used for queue pairs.
+ * memory that can be used for queue pairs. Since each queue pair
+ * consists of at least two pages, the memory limit also dictates the
+ * number of queue pairs a guest can create.
*/
#define VMCI_MAX_GUEST_QP_MEMORY (128 * 1024 * 1024)
+#define VMCI_MAX_GUEST_QP_COUNT (VMCI_MAX_GUEST_QP_MEMORY / PAGE_SIZE / 2)
+
+/*
+ * There can be at most PAGE_SIZE doorbells since there is one doorbell
+ * per byte in the doorbell bitmap page.
+ */
+#define VMCI_MAX_GUEST_DOORBELL_COUNT PAGE_SIZE
/*
* Queues with pre-mapped data pages must be small, so that we don't pin
@@ -438,8 +439,8 @@ enum {
struct vmci_queue_header {
/* All fields are 64bit and aligned. */
struct vmci_handle handle; /* Identifier. */
- atomic64_t producer_tail; /* Offset in this queue. */
- atomic64_t consumer_head; /* Offset in peer queue. */
+ u64 producer_tail; /* Offset in this queue. */
+ u64 consumer_head; /* Offset in peer queue. */
};
/*
@@ -740,13 +741,9 @@ static inline void *vmci_event_data_payload(struct vmci_event_data *ev_data)
* prefix will be used, so correctness isn't an issue, but using a
* 64bit operation still adds unnecessary overhead.
*/
-static inline u64 vmci_q_read_pointer(atomic64_t *var)
+static inline u64 vmci_q_read_pointer(u64 *var)
{
-#if defined(CONFIG_X86_32)
- return atomic_read((atomic_t *)var);
-#else
- return atomic64_read(var);
-#endif
+ return READ_ONCE(*(unsigned long *)var);
}
/*
@@ -755,23 +752,17 @@ static inline u64 vmci_q_read_pointer(atomic64_t *var)
* never exceeds a 32bit value in this case. On 32bit SMP, using a
* locked cmpxchg8b adds unnecessary overhead.
*/
-static inline void vmci_q_set_pointer(atomic64_t *var,
- u64 new_val)
+static inline void vmci_q_set_pointer(u64 *var, u64 new_val)
{
-#if defined(CONFIG_X86_32)
- return atomic_set((atomic_t *)var, (u32)new_val);
-#else
- return atomic64_set(var, new_val);
-#endif
+ /* XXX buggered on big-endian */
+ WRITE_ONCE(*(unsigned long *)var, (unsigned long)new_val);
}
/*
* Helper to add a given offset to a head or tail pointer. Wraps the
* value of the pointer around the max size of the queue.
*/
-static inline void vmci_qp_add_pointer(atomic64_t *var,
- size_t add,
- u64 size)
+static inline void vmci_qp_add_pointer(u64 *var, size_t add, u64 size)
{
u64 new_val = vmci_q_read_pointer(var);
@@ -848,8 +839,8 @@ static inline void vmci_q_header_init(struct vmci_queue_header *q_header,
const struct vmci_handle handle)
{
q_header->handle = handle;
- atomic64_set(&q_header->producer_tail, 0);
- atomic64_set(&q_header->consumer_head, 0);
+ q_header->producer_tail = 0;
+ q_header->consumer_head = 0;
}
/*