/*
* Copyright 2016-17 IBM Corp.
*
* 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; either version
* 2 of the License, or (at your option) any later version.
*/
#define pr_fmt(fmt) "vas: " fmt
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/log2.h>
#include <linux/rcupdate.h>
#include <linux/cred.h>
#include "vas.h"
#include "copy-paste.h"
/*
* Compute the paste address region for the window @window using the
* ->paste_base_addr and ->paste_win_id_shift we got from device tree.
*/
static void compute_paste_address(struct vas_window *window, u64 *addr, int *len)
{
int winid;
u64 base, shift;
base = window->vinst->paste_base_addr;
shift = window->vinst->paste_win_id_shift;
winid = window->winid;
*addr = base + (winid << shift);
if (len)
*len = PAGE_SIZE;
pr_debug("Txwin #%d: Paste addr 0x%llx\n", winid, *addr);
}
static inline void get_hvwc_mmio_bar(struct vas_window *window,
u64 *start, int *len)
{
u64 pbaddr;
pbaddr = window->vinst->hvwc_bar_start;
*start = pbaddr + window->winid * VAS_HVWC_SIZE;
*len = VAS_HVWC_SIZE;
}
static inline void get_uwc_mmio_bar(struct vas_window *window,
u64 *start, int *len)
{
u64 pbaddr;
pbaddr = window->vinst->uwc_bar_start;
*start = pbaddr + window->winid * VAS_UWC_SIZE;
*len = VAS_UWC_SIZE;
}
/*
* Map the paste bus address of the given send window into kernel address
* space. Unlike MMIO regions (map_mmio_region() below), paste region must
* be mapped cache-able and is only applicable to send windows.
*/
static void *map_paste_region(struct vas_window *txwin)
{
int len;
void *map;
char *name;
u64 start;
name = kasprintf(GFP_KERNEL, "window-v%d-w%d", txwin->vinst->vas_id,
txwin->winid);
if (!name)
goto free_name;
txwin->paste_addr_name = name;
compute_paste_address(txwin, &start, &len);
if (!request_mem_region(start, len, name)) {
pr_devel("%s(): request_mem_region(0x%llx, %d) failed\n",
__func__, start, len);
goto free_name;
}
map = ioremap_cache(start, len);
if (!map) {
pr_devel("%s(): ioremap_cache(0x%llx, %d) failed\n", __func__,
start, len);
goto free_name;
}
pr_devel("Mapped paste addr 0x%llx to kaddr 0x%p\n", start, map);
return map;
free_name:
kfree(name);
return ERR_PTR(-ENOMEM);
}
static void *map_mmio_region(char *name, u64 start, int len)
{
void *map;
if (!request_mem_region(start, len, name)) {
pr_devel("%s(): request_mem_region(0x%llx, %d) failed\n",
__func__, start, len);
return NULL;
}
map = ioremap(start, len);
if (!map) {
pr_devel("%s(): ioremap(0x%llx, %d) failed\n", __func__, start,
len);
return NULL;
}
return map