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34#include <linux/mm.h>
35#include <linux/device.h>
36#include <linux/slab.h>
37#include <linux/sched.h>
38
39#include "ipath_kernel.h"
40
41static void __ipath_release_user_pages(struct page **p, size_t num_pages,
42 int dirty)
43{
44 size_t i;
45
46 for (i = 0; i < num_pages; i++) {
47 ipath_cdbg(MM, "%lu/%lu put_page %p\n", (unsigned long) i,
48 (unsigned long) num_pages, p[i]);
49 if (dirty)
50 set_page_dirty_lock(p[i]);
51 put_page(p[i]);
52 }
53}
54
55
56static int __get_user_pages(unsigned long start_page, size_t num_pages,
57 struct page **p, struct vm_area_struct **vma)
58{
59 unsigned long lock_limit;
60 size_t got;
61 int ret;
62
63 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
64
65 if (num_pages > lock_limit) {
66 ret = -ENOMEM;
67 goto bail;
68 }
69
70 ipath_cdbg(VERBOSE, "pin %lx pages from vaddr %lx\n",
71 (unsigned long) num_pages, start_page);
72
73 for (got = 0; got < num_pages; got += ret) {
74 ret = get_user_pages(current, current->mm,
75 start_page + got * PAGE_SIZE,
76 num_pages - got, 1, 1,
77 p + got, vma);
78 if (ret < 0)
79 goto bail_release;
80 }
81
82 current->mm->locked_vm += num_pages;
83
84 ret = 0;
85 goto bail;
86
87bail_release:
88 __ipath_release_user_pages(p, got, 0);
89bail:
90 return ret;
91}
92
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105
106dma_addr_t ipath_map_page(struct pci_dev *hwdev, struct page *page,
107 unsigned long offset, size_t size, int direction)
108{
109 dma_addr_t phys;
110
111 phys = pci_map_page(hwdev, page, offset, size, direction);
112
113 if (phys == 0) {
114 pci_unmap_page(hwdev, phys, size, direction);
115 phys = pci_map_page(hwdev, page, offset, size, direction);
116
117
118
119
120 }
121
122 return phys;
123}
124
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129
130dma_addr_t ipath_map_single(struct pci_dev *hwdev, void *ptr, size_t size,
131 int direction)
132{
133 dma_addr_t phys;
134
135 phys = pci_map_single(hwdev, ptr, size, direction);
136
137 if (phys == 0) {
138 pci_unmap_single(hwdev, phys, size, direction);
139 phys = pci_map_single(hwdev, ptr, size, direction);
140
141
142
143
144 }
145
146 return phys;
147}
148
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159
160
161int ipath_get_user_pages(unsigned long start_page, size_t num_pages,
162 struct page **p)
163{
164 int ret;
165
166 down_write(¤t->mm->mmap_sem);
167
168 ret = __get_user_pages(start_page, num_pages, p, NULL);
169
170 up_write(¤t->mm->mmap_sem);
171
172 return ret;
173}
174
175void ipath_release_user_pages(struct page **p, size_t num_pages)
176{
177 down_write(¤t->mm->mmap_sem);
178
179 __ipath_release_user_pages(p, num_pages, 1);
180
181 current->mm->locked_vm -= num_pages;
182
183 up_write(¤t->mm->mmap_sem);
184}
185
186struct ipath_user_pages_work {
187 struct work_struct work;
188 struct mm_struct *mm;
189 unsigned long num_pages;
190};
191
192static void user_pages_account(struct work_struct *_work)
193{
194 struct ipath_user_pages_work *work =
195 container_of(_work, struct ipath_user_pages_work, work);
196
197 down_write(&work->mm->mmap_sem);
198 work->mm->locked_vm -= work->num_pages;
199 up_write(&work->mm->mmap_sem);
200 mmput(work->mm);
201 kfree(work);
202}
203
204void ipath_release_user_pages_on_close(struct page **p, size_t num_pages)
205{
206 struct ipath_user_pages_work *work;
207 struct mm_struct *mm;
208
209 __ipath_release_user_pages(p, num_pages, 1);
210
211 mm = get_task_mm(current);
212 if (!mm)
213 return;
214
215 work = kmalloc(sizeof(*work), GFP_KERNEL);
216 if (!work)
217 goto bail_mm;
218
219 INIT_WORK(&work->work, user_pages_account);
220 work->mm = mm;
221 work->num_pages = num_pages;
222
223 queue_work(ib_wq, &work->work);
224 return;
225
226bail_mm:
227 mmput(mm);
228 return;
229}
230