1/* 2 * 3 * Copyright (c) 2009, Microsoft Corporation. 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms and conditions of the GNU General Public License, 7 * version 2, as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along with 15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple 16 * Place - Suite 330, Boston, MA 02111-1307 USA. 17 * 18 * Authors: 19 * Haiyang Zhang <haiyangz@microsoft.com> 20 * Hank Janssen <hjanssen@microsoft.com> 21 * 22 */ 23 24#include <linux/module.h> 25#include <linux/init.h> 26#include <linux/types.h> 27#include <linux/mm.h> 28#include <linux/highmem.h> 29#include <linux/vmalloc.h> 30#include <linux/ioport.h> 31#include <linux/irq.h> 32#include <linux/interrupt.h> 33#include <linux/sched.h> 34#include <linux/wait.h> 35#include <linux/spinlock.h> 36#include <linux/workqueue.h> 37#include <linux/kernel.h> 38#include <linux/jiffies.h> 39#include <linux/delay.h> 40#include <linux/time.h> 41#include <linux/io.h> 42#include <linux/bitops.h> 43#include <linux/slab.h> 44#include "osd.h" 45 46struct osd_callback_struct { 47 struct work_struct work; 48 void (*callback)(void *); 49 void *data; 50}; 51 52void *osd_VirtualAllocExec(unsigned int size) 53{ 54#ifdef __x86_64__ 55 return __vmalloc(size, GFP_KERNEL, PAGE_KERNEL_EXEC); 56#else 57 return __vmalloc(size, GFP_KERNEL, 58 __pgprot(__PAGE_KERNEL & (~_PAGE_NX))); 59#endif 60} 61 62/** 63 * osd_PageAlloc() - Allocate pages 64 * @count: Total number of Kernel pages you want to allocate 65 * 66 * Tries to allocate @count number of consecutive free kernel pages. 67 * And if successful, it will set the pages to 0 before returning. 68 * If successfull it will return pointer to the @count pages. 69 * Mainly used by Hyper-V drivers. 70 */ 71void *osd_PageAlloc(unsigned int count) 72{ 73 void *p; 74 75 p = (void *)__get_free_pages(GFP_KERNEL, get_order(count * PAGE_SIZE)); 76 if (p) 77 memset(p, 0, count * PAGE_SIZE); 78 return p; 79 80 /* struct page* page = alloc_page(GFP_KERNEL|__GFP_ZERO); */ 81 /* void *p; */ 82 83 /* BUGBUG: We need to use kmap in case we are in HIMEM region */ 84 /* p = page_address(page); */ 85 /* if (p) memset(p, 0, PAGE_SIZE); */ 86 /* return p; */ 87} 88EXPORT_SYMBOL_GPL(osd_PageAlloc); 89 90/** 91 * osd_PageFree() - Free pages 92 * @page: Pointer to the first page to be freed 93 * @count: Total number of Kernel pages you free 94 * 95 * Frees the pages allocated by osd_PageAlloc() 96 * Mainly used by Hyper-V drivers. 97 */ 98void osd_PageFree(void *page, unsigned int count) 99{ 100 free_pages((unsigned long)page, get_order(count * PAGE_SIZE)); 101 /*struct page* p = virt_to_page(page); 102 __free_page(p);*/ 103} 104EXPORT_SYMBOL_GPL(osd_PageFree); 105 106/** 107 * osd_WaitEventCreate() - Create the event queue 108 * 109 * Allocates memory for a &struct osd_waitevent. And then calls 110 * init_waitqueue_head to set up the wait queue for the event. 111 * This structure is usually part of a another structure that contains 112 * the actual Hyper-V device driver structure. 113 * 114 * Returns pointer to &struct osd_waitevent 115 * Mainly used by Hyper-V drivers. 116 */ 117struct osd_waitevent *osd_WaitEventCreate(void) 118{ 119 struct osd_waitevent *wait = kmalloc(sizeof(struct osd_waitevent), 120 GFP_KERNEL); 121 if (!wait) 122 return NULL; 123 124 wait->condition = 0; 125 init_waitqueue_head(&wait->event); 126 return wait; 127} 128EXPORT_SYMBOL_GPL(osd_WaitEventCreate); 129 130 131/** 132 * osd_WaitEventSet() - Wake up the process 133 * @waitEvent: Structure to event to be woken up 134 * 135 * @waitevent is of type &struct osd_waitevent 136 * 137 * Wake up the sleeping process so it can do some work. 138 * And set condition indicator in &struct osd_waitevent to indicate 139 * the process is in a woken state. 140 * 141 * Only used by Network and Storage Hyper-V drivers. 142 */ 143void osd_WaitEventSet(struct osd_waitevent *waitEvent) 144{ 145 waitEvent->condition = 1; 146 wake_up_interruptible(&waitEvent->event); 147} 148EXPORT_SYMBOL_GPL(osd_WaitEventSet); 149 150/** 151 * osd_WaitEventWait() - Wait for event till condition is true 152 * @waitEvent: Structure to event to be put to sleep 153 * 154 * @waitevent is of type &struct osd_waitevent 155 * 156 * Set up the process to sleep until waitEvent->condition get true. 157 * And set condition indicator in &struct osd_waitevent to indicate 158 * the process is in a sleeping state. 159 * 160 * Returns the status of 'wait_event_interruptible()' system call 161 * 162 * Mainly used by Hyper-V drivers. 163 */ 164int osd_WaitEventWait(struct osd_waitevent *waitEvent) 165{ 166 int ret = 0; 167 168 ret = wait_event_interruptible(waitEvent->event, 169 waitEvent->condition); 170 waitEvent->condition = 0; 171 return ret; 172} 173EXPORT_SYMBOL_GPL(osd_WaitEventWait); 174 175/** 176 * osd_WaitEventWaitEx() - Wait for event or timeout for process wakeup 177 * @waitEvent: Structure to event to be put to sleep 178 * @TimeoutInMs: Total number of Milliseconds to wait before waking up 179 * 180 * @waitevent is of type &struct osd_waitevent 181 * Set up the process to sleep until @waitEvent->condition get true or 182 * @TimeoutInMs (Time out in Milliseconds) has been reached. 183 * And set condition indicator in &struct osd_waitevent to indicate 184 * the process is in a sleeping state. 185 * 186 * Returns the status of 'wait_event_interruptible_timeout()' system call 187 * 188 * Mainly used by Hyper-V drivers. 189 */ 190int osd_WaitEventWaitEx(struct osd_waitevent *waitEvent, u32 TimeoutInMs) 191{ 192 int ret = 0; 193 194 ret = wait_event_interruptible_timeout(waitEvent->event, 195 waitEvent->condition, 196 msecs_to_jiffies(TimeoutInMs)); 197 waitEvent->condition = 0; 198 return ret; 199} 200EXPORT_SYMBOL_GPL(osd_WaitEventWaitEx); 201 202static void osd_callback_work(struct work_struct *work) 203{ 204 struct osd_callback_struct *cb = container_of(work, 205 struct osd_callback_struct, 206 work); 207 (cb->callback)(cb->data); 208 kfree(cb); 209} 210 211int osd_schedule_callback(struct workqueue_struct *wq, 212 void (*func)(void *), 213 void *data) 214{ 215 struct osd_callback_struct *cb; 216 217 cb = kmalloc(sizeof(*cb), GFP_KERNEL); 218 if (!cb) { 219 printk(KERN_ERR "unable to allocate memory in osd_schedule_callback\n"); 220 return -1; 221 } 222 223 cb->callback = func; 224 cb->data = data; 225 INIT_WORK(&cb->work, osd_callback_work); 226 return queue_work(wq, &cb->work); 227} 228