diff options
Diffstat (limited to 'drivers/staging/vboxvideo/vbox_hgsmi.c')
| -rw-r--r-- | drivers/staging/vboxvideo/vbox_hgsmi.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/drivers/staging/vboxvideo/vbox_hgsmi.c b/drivers/staging/vboxvideo/vbox_hgsmi.c new file mode 100644 index 000000000000..822fd31121cb --- /dev/null +++ b/drivers/staging/vboxvideo/vbox_hgsmi.c @@ -0,0 +1,115 @@ +/* + * Copyright (C) 2017 Oracle Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * Authors: Hans de Goede <hdegoede@redhat.com> + */ + +#include "vbox_drv.h" +#include "vboxvideo_vbe.h" +#include "hgsmi_defs.h" + +/* One-at-a-Time Hash from http://www.burtleburtle.net/bob/hash/doobs.html */ +static u32 hgsmi_hash_process(u32 hash, const u8 *data, int size) +{ + while (size--) { + hash += *data++; + hash += (hash << 10); + hash ^= (hash >> 6); + } + + return hash; +} + +static u32 hgsmi_hash_end(u32 hash) +{ + hash += (hash << 3); + hash ^= (hash >> 11); + hash += (hash << 15); + + return hash; +} + +/* Not really a checksum but that is the naming used in all vbox code */ +static u32 hgsmi_checksum(u32 offset, + const struct hgsmi_buffer_header *header, + const struct hgsmi_buffer_tail *tail) +{ + u32 checksum; + + checksum = hgsmi_hash_process(0, (u8 *)&offset, sizeof(offset)); + checksum = hgsmi_hash_process(checksum, (u8 *)header, sizeof(*header)); + /* 4 -> Do not checksum the checksum itself */ + checksum = hgsmi_hash_process(checksum, (u8 *)tail, 4); + + return hgsmi_hash_end(checksum); +} + +void *hgsmi_buffer_alloc(struct gen_pool *guest_pool, size_t size, + u8 channel, u16 channel_info) +{ + struct hgsmi_buffer_header *h; + struct hgsmi_buffer_tail *t; + size_t total_size; + dma_addr_t offset; + + total_size = size + sizeof(*h) + sizeof(*t); + h = gen_pool_dma_alloc(guest_pool, total_size, &offset); + if (!h) + return NULL; + + t = (struct hgsmi_buffer_tail *)((u8 *)h + sizeof(*h) + size); + + h->flags = HGSMI_BUFFER_HEADER_F_SEQ_SINGLE; + h->data_size = size; + h->channel = channel; + h->channel_info = channel_info; + memset(&h->u.header_data, 0, sizeof(h->u.header_data)); + + t->reserved = 0; + t->checksum = hgsmi_checksum(offset, h, t); + + return (u8 *)h + sizeof(*h); +} + +void hgsmi_buffer_free(struct gen_pool *guest_pool, void *buf) +{ + struct hgsmi_buffer_header *h = + (struct hgsmi_buffer_header *)((u8 *)buf - sizeof(*h)); + size_t total_size = h->data_size + sizeof(*h) + + sizeof(struct hgsmi_buffer_tail); + + gen_pool_free(guest_pool, (unsigned long)h, total_size); +} + +int hgsmi_buffer_submit(struct gen_pool *guest_pool, void *buf) +{ + phys_addr_t offset; + + offset = gen_pool_virt_to_phys(guest_pool, (unsigned long)buf - + sizeof(struct hgsmi_buffer_header)); + outl(offset, VGA_PORT_HGSMI_GUEST); + /* Make the compiler aware that the host has changed memory. */ + mb(); + + return 0; +} |