diff options
Diffstat (limited to 'include/linux/vmw_vmci_defs.h')
-rw-r--r-- | include/linux/vmw_vmci_defs.h | 51 |
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; } /* |