diff options
Diffstat (limited to 'mm/filemap_xip.c')
-rw-r--r-- | mm/filemap_xip.c | 200 |
1 files changed, 100 insertions, 100 deletions
diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c index 5e598c42afd7..3e744abcce9d 100644 --- a/mm/filemap_xip.c +++ b/mm/filemap_xip.c | |||
@@ -15,6 +15,7 @@ | |||
15 | #include <linux/rmap.h> | 15 | #include <linux/rmap.h> |
16 | #include <linux/sched.h> | 16 | #include <linux/sched.h> |
17 | #include <asm/tlbflush.h> | 17 | #include <asm/tlbflush.h> |
18 | #include <asm/io.h> | ||
18 | 19 | ||
19 | /* | 20 | /* |
20 | * We do use our own empty page to avoid interference with other users | 21 | * We do use our own empty page to avoid interference with other users |
@@ -42,37 +43,41 @@ static struct page *xip_sparse_page(void) | |||
42 | 43 | ||
43 | /* | 44 | /* |
44 | * This is a file read routine for execute in place files, and uses | 45 | * This is a file read routine for execute in place files, and uses |
45 | * the mapping->a_ops->get_xip_page() function for the actual low-level | 46 | * the mapping->a_ops->get_xip_mem() function for the actual low-level |
46 | * stuff. | 47 | * stuff. |
47 | * | 48 | * |
48 | * Note the struct file* is not used at all. It may be NULL. | 49 | * Note the struct file* is not used at all. It may be NULL. |
49 | */ | 50 | */ |
50 | static void | 51 | static ssize_t |
51 | do_xip_mapping_read(struct address_space *mapping, | 52 | do_xip_mapping_read(struct address_space *mapping, |
52 | struct file_ra_state *_ra, | 53 | struct file_ra_state *_ra, |
53 | struct file *filp, | 54 | struct file *filp, |
54 | loff_t *ppos, | 55 | char __user *buf, |
55 | read_descriptor_t *desc, | 56 | size_t len, |
56 | read_actor_t actor) | 57 | loff_t *ppos) |
57 | { | 58 | { |
58 | struct inode *inode = mapping->host; | 59 | struct inode *inode = mapping->host; |
59 | pgoff_t index, end_index; | 60 | pgoff_t index, end_index; |
60 | unsigned long offset; | 61 | unsigned long offset; |
61 | loff_t isize; | 62 | loff_t isize, pos; |
63 | size_t copied = 0, error = 0; | ||
62 | 64 | ||
63 | BUG_ON(!mapping->a_ops->get_xip_page); | 65 | BUG_ON(!mapping->a_ops->get_xip_mem); |
64 | 66 | ||
65 | index = *ppos >> PAGE_CACHE_SHIFT; | 67 | pos = *ppos; |
66 | offset = *ppos & ~PAGE_CACHE_MASK; | 68 | index = pos >> PAGE_CACHE_SHIFT; |
69 | offset = pos & ~PAGE_CACHE_MASK; | ||
67 | 70 | ||
68 | isize = i_size_read(inode); | 71 | isize = i_size_read(inode); |
69 | if (!isize) | 72 | if (!isize) |
70 | goto out; | 73 | goto out; |
71 | 74 | ||
72 | end_index = (isize - 1) >> PAGE_CACHE_SHIFT; | 75 | end_index = (isize - 1) >> PAGE_CACHE_SHIFT; |
73 | for (;;) { | 76 | do { |
74 | struct page *page; | 77 | unsigned long nr, left; |
75 | unsigned long nr, ret; | 78 | void *xip_mem; |
79 | unsigned long xip_pfn; | ||
80 | int zero = 0; | ||
76 | 81 | ||
77 | /* nr is the maximum number of bytes to copy from this page */ | 82 | /* nr is the maximum number of bytes to copy from this page */ |
78 | nr = PAGE_CACHE_SIZE; | 83 | nr = PAGE_CACHE_SIZE; |
@@ -85,19 +90,17 @@ do_xip_mapping_read(struct address_space *mapping, | |||
85 | } | 90 | } |
86 | } | 91 | } |
87 | nr = nr - offset; | 92 | nr = nr - offset; |
93 | if (nr > len) | ||
94 | nr = len; | ||
88 | 95 | ||
89 | page = mapping->a_ops->get_xip_page(mapping, | 96 | error = mapping->a_ops->get_xip_mem(mapping, index, 0, |
90 | index*(PAGE_SIZE/512), 0); | 97 | &xip_mem, &xip_pfn); |
91 | if (!page) | 98 | if (unlikely(error)) { |
92 | goto no_xip_page; | 99 | if (error == -ENODATA) { |
93 | if (unlikely(IS_ERR(page))) { | ||
94 | if (PTR_ERR(page) == -ENODATA) { | ||
95 | /* sparse */ | 100 | /* sparse */ |
96 | page = ZERO_PAGE(0); | 101 | zero = 1; |
97 | } else { | 102 | } else |
98 | desc->error = PTR_ERR(page); | ||
99 | goto out; | 103 | goto out; |
100 | } | ||
101 | } | 104 | } |
102 | 105 | ||
103 | /* If users can be writing to this page using arbitrary | 106 | /* If users can be writing to this page using arbitrary |
@@ -105,10 +108,10 @@ do_xip_mapping_read(struct address_space *mapping, | |||
105 | * before reading the page on the kernel side. | 108 | * before reading the page on the kernel side. |
106 | */ | 109 | */ |
107 | if (mapping_writably_mapped(mapping)) | 110 | if (mapping_writably_mapped(mapping)) |
108 | flush_dcache_page(page); | 111 | /* address based flush */ ; |
109 | 112 | ||
110 | /* | 113 | /* |
111 | * Ok, we have the page, so now we can copy it to user space... | 114 | * Ok, we have the mem, so now we can copy it to user space... |
112 | * | 115 | * |
113 | * The actor routine returns how many bytes were actually used.. | 116 | * The actor routine returns how many bytes were actually used.. |
114 | * NOTE! This may not be the same as how much of a user buffer | 117 | * NOTE! This may not be the same as how much of a user buffer |
@@ -116,47 +119,38 @@ do_xip_mapping_read(struct address_space *mapping, | |||
116 | * "pos" here (the actor routine has to update the user buffer | 119 | * "pos" here (the actor routine has to update the user buffer |
117 | * pointers and the remaining count). | 120 | * pointers and the remaining count). |
118 | */ | 121 | */ |
119 | ret = actor(desc, page, offset, nr); | 122 | if (!zero) |
120 | offset += ret; | 123 | left = __copy_to_user(buf+copied, xip_mem+offset, nr); |
121 | index += offset >> PAGE_CACHE_SHIFT; | 124 | else |
122 | offset &= ~PAGE_CACHE_MASK; | 125 | left = __clear_user(buf + copied, nr); |
123 | 126 | ||
124 | if (ret == nr && desc->count) | 127 | if (left) { |
125 | continue; | 128 | error = -EFAULT; |
126 | goto out; | 129 | goto out; |
130 | } | ||
127 | 131 | ||
128 | no_xip_page: | 132 | copied += (nr - left); |
129 | /* Did not get the page. Report it */ | 133 | offset += (nr - left); |
130 | desc->error = -EIO; | 134 | index += offset >> PAGE_CACHE_SHIFT; |
131 | goto out; | 135 | offset &= ~PAGE_CACHE_MASK; |
132 | } | 136 | } while (copied < len); |
133 | 137 | ||
134 | out: | 138 | out: |
135 | *ppos = ((loff_t) index << PAGE_CACHE_SHIFT) + offset; | 139 | *ppos = pos + copied; |
136 | if (filp) | 140 | if (filp) |
137 | file_accessed(filp); | 141 | file_accessed(filp); |
142 | |||
143 | return (copied ? copied : error); | ||
138 | } | 144 | } |
139 | 145 | ||
140 | ssize_t | 146 | ssize_t |
141 | xip_file_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) | 147 | xip_file_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
142 | { | 148 | { |
143 | read_descriptor_t desc; | ||
144 | |||
145 | if (!access_ok(VERIFY_WRITE, buf, len)) | 149 | if (!access_ok(VERIFY_WRITE, buf, len)) |
146 | return -EFAULT; | 150 | return -EFAULT; |
147 | 151 | ||
148 | desc.written = 0; | 152 | return do_xip_mapping_read(filp->f_mapping, &filp->f_ra, filp, |
149 | desc.arg.buf = buf; | 153 | buf, len, ppos); |
150 | desc.count = len; | ||
151 | desc.error = 0; | ||
152 | |||
153 | do_xip_mapping_read(filp->f_mapping, &filp->f_ra, filp, | ||
154 | ppos, &desc, file_read_actor); | ||
155 | |||
156 | if (desc.written) | ||
157 | return desc.written; | ||
158 | else | ||
159 | return desc.error; | ||
160 | } | 154 | } |
161 | EXPORT_SYMBOL_GPL(xip_file_read); | 155 | EXPORT_SYMBOL_GPL(xip_file_read); |
162 | 156 | ||
@@ -211,13 +205,16 @@ __xip_unmap (struct address_space * mapping, | |||
211 | * | 205 | * |
212 | * This function is derived from filemap_fault, but used for execute in place | 206 | * This function is derived from filemap_fault, but used for execute in place |
213 | */ | 207 | */ |
214 | static int xip_file_fault(struct vm_area_struct *area, struct vm_fault *vmf) | 208 | static int xip_file_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
215 | { | 209 | { |
216 | struct file *file = area->vm_file; | 210 | struct file *file = vma->vm_file; |
217 | struct address_space *mapping = file->f_mapping; | 211 | struct address_space *mapping = file->f_mapping; |
218 | struct inode *inode = mapping->host; | 212 | struct inode *inode = mapping->host; |
219 | struct page *page; | ||
220 | pgoff_t size; | 213 | pgoff_t size; |
214 | void *xip_mem; | ||
215 | unsigned long xip_pfn; | ||
216 | struct page *page; | ||
217 | int error; | ||
221 | 218 | ||
222 | /* XXX: are VM_FAULT_ codes OK? */ | 219 | /* XXX: are VM_FAULT_ codes OK? */ |
223 | 220 | ||
@@ -225,35 +222,44 @@ static int xip_file_fault(struct vm_area_struct *area, struct vm_fault *vmf) | |||
225 | if (vmf->pgoff >= size) | 222 | if (vmf->pgoff >= size) |
226 | return VM_FAULT_SIGBUS; | 223 | return VM_FAULT_SIGBUS; |
227 | 224 | ||
228 | page = mapping->a_ops->get_xip_page(mapping, | 225 | error = mapping->a_ops->get_xip_mem(mapping, vmf->pgoff, 0, |
229 | vmf->pgoff*(PAGE_SIZE/512), 0); | 226 | &xip_mem, &xip_pfn); |
230 | if (!IS_ERR(page)) | 227 | if (likely(!error)) |
231 | goto out; | 228 | goto found; |
232 | if (PTR_ERR(page) != -ENODATA) | 229 | if (error != -ENODATA) |
233 | return VM_FAULT_OOM; | 230 | return VM_FAULT_OOM; |
234 | 231 | ||
235 | /* sparse block */ | 232 | /* sparse block */ |
236 | if ((area->vm_flags & (VM_WRITE | VM_MAYWRITE)) && | 233 | if ((vma->vm_flags & (VM_WRITE | VM_MAYWRITE)) && |
237 | (area->vm_flags & (VM_SHARED| VM_MAYSHARE)) && | 234 | (vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) && |
238 | (!(mapping->host->i_sb->s_flags & MS_RDONLY))) { | 235 | (!(mapping->host->i_sb->s_flags & MS_RDONLY))) { |
236 | int err; | ||
237 | |||
239 | /* maybe shared writable, allocate new block */ | 238 | /* maybe shared writable, allocate new block */ |
240 | page = mapping->a_ops->get_xip_page(mapping, | 239 | error = mapping->a_ops->get_xip_mem(mapping, vmf->pgoff, 1, |
241 | vmf->pgoff*(PAGE_SIZE/512), 1); | 240 | &xip_mem, &xip_pfn); |
242 | if (IS_ERR(page)) | 241 | if (error) |
243 | return VM_FAULT_SIGBUS; | 242 | return VM_FAULT_SIGBUS; |
244 | /* unmap page at pgoff from all other vmas */ | 243 | /* unmap sparse mappings at pgoff from all other vmas */ |
245 | __xip_unmap(mapping, vmf->pgoff); | 244 | __xip_unmap(mapping, vmf->pgoff); |
245 | |||
246 | found: | ||
247 | err = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, | ||
248 | xip_pfn); | ||
249 | if (err == -ENOMEM) | ||
250 | return VM_FAULT_OOM; | ||
251 | BUG_ON(err); | ||
252 | return VM_FAULT_NOPAGE; | ||
246 | } else { | 253 | } else { |
247 | /* not shared and writable, use xip_sparse_page() */ | 254 | /* not shared and writable, use xip_sparse_page() */ |
248 | page = xip_sparse_page(); | 255 | page = xip_sparse_page(); |
249 | if (!page) | 256 | if (!page) |
250 | return VM_FAULT_OOM; | 257 | return VM_FAULT_OOM; |
251 | } | ||
252 | 258 | ||
253 | out: | 259 | page_cache_get(page); |
254 | page_cache_get(page); | 260 | vmf->page = page; |
255 | vmf->page = page; | 261 | return 0; |
256 | return 0; | 262 | } |
257 | } | 263 | } |
258 | 264 | ||
259 | static struct vm_operations_struct xip_file_vm_ops = { | 265 | static struct vm_operations_struct xip_file_vm_ops = { |
@@ -262,11 +268,11 @@ static struct vm_operations_struct xip_file_vm_ops = { | |||
262 | 268 | ||
263 | int xip_file_mmap(struct file * file, struct vm_area_struct * vma) | 269 | int xip_file_mmap(struct file * file, struct vm_area_struct * vma) |
264 | { | 270 | { |
265 | BUG_ON(!file->f_mapping->a_ops->get_xip_page); | 271 | BUG_ON(!file->f_mapping->a_ops->get_xip_mem); |
266 | 272 | ||
267 | file_accessed(file); | 273 | file_accessed(file); |
268 | vma->vm_ops = &xip_file_vm_ops; | 274 | vma->vm_ops = &xip_file_vm_ops; |
269 | vma->vm_flags |= VM_CAN_NONLINEAR; | 275 | vma->vm_flags |= VM_CAN_NONLINEAR | VM_MIXEDMAP; |
270 | return 0; | 276 | return 0; |
271 | } | 277 | } |
272 | EXPORT_SYMBOL_GPL(xip_file_mmap); | 278 | EXPORT_SYMBOL_GPL(xip_file_mmap); |
@@ -279,17 +285,17 @@ __xip_file_write(struct file *filp, const char __user *buf, | |||
279 | const struct address_space_operations *a_ops = mapping->a_ops; | 285 | const struct address_space_operations *a_ops = mapping->a_ops; |
280 | struct inode *inode = mapping->host; | 286 | struct inode *inode = mapping->host; |
281 | long status = 0; | 287 | long status = 0; |
282 | struct page *page; | ||
283 | size_t bytes; | 288 | size_t bytes; |
284 | ssize_t written = 0; | 289 | ssize_t written = 0; |
285 | 290 | ||
286 | BUG_ON(!mapping->a_ops->get_xip_page); | 291 | BUG_ON(!mapping->a_ops->get_xip_mem); |
287 | 292 | ||
288 | do { | 293 | do { |
289 | unsigned long index; | 294 | unsigned long index; |
290 | unsigned long offset; | 295 | unsigned long offset; |
291 | size_t copied; | 296 | size_t copied; |
292 | char *kaddr; | 297 | void *xip_mem; |
298 | unsigned long xip_pfn; | ||
293 | 299 | ||
294 | offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */ | 300 | offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */ |
295 | index = pos >> PAGE_CACHE_SHIFT; | 301 | index = pos >> PAGE_CACHE_SHIFT; |
@@ -297,28 +303,22 @@ __xip_file_write(struct file *filp, const char __user *buf, | |||
297 | if (bytes > count) | 303 | if (bytes > count) |
298 | bytes = count; | 304 | bytes = count; |
299 | 305 | ||
300 | page = a_ops->get_xip_page(mapping, | 306 | status = a_ops->get_xip_mem(mapping, index, 0, |
301 | index*(PAGE_SIZE/512), 0); | 307 | &xip_mem, &xip_pfn); |
302 | if (IS_ERR(page) && (PTR_ERR(page) == -ENODATA)) { | 308 | if (status == -ENODATA) { |
303 | /* we allocate a new page unmap it */ | 309 | /* we allocate a new page unmap it */ |
304 | page = a_ops->get_xip_page(mapping, | 310 | status = a_ops->get_xip_mem(mapping, index, 1, |
305 | index*(PAGE_SIZE/512), 1); | 311 | &xip_mem, &xip_pfn); |
306 | if (!IS_ERR(page)) | 312 | if (!status) |
307 | /* unmap page at pgoff from all other vmas */ | 313 | /* unmap page at pgoff from all other vmas */ |
308 | __xip_unmap(mapping, index); | 314 | __xip_unmap(mapping, index); |
309 | } | 315 | } |
310 | 316 | ||
311 | if (IS_ERR(page)) { | 317 | if (status) |
312 | status = PTR_ERR(page); | ||
313 | break; | 318 | break; |
314 | } | ||
315 | 319 | ||
316 | fault_in_pages_readable(buf, bytes); | ||
317 | kaddr = kmap_atomic(page, KM_USER0); | ||
318 | copied = bytes - | 320 | copied = bytes - |
319 | __copy_from_user_inatomic_nocache(kaddr + offset, buf, bytes); | 321 | __copy_from_user_nocache(xip_mem + offset, buf, bytes); |
320 | kunmap_atomic(kaddr, KM_USER0); | ||
321 | flush_dcache_page(page); | ||
322 | 322 | ||
323 | if (likely(copied > 0)) { | 323 | if (likely(copied > 0)) { |
324 | status = copied; | 324 | status = copied; |
@@ -398,7 +398,7 @@ EXPORT_SYMBOL_GPL(xip_file_write); | |||
398 | 398 | ||
399 | /* | 399 | /* |
400 | * truncate a page used for execute in place | 400 | * truncate a page used for execute in place |
401 | * functionality is analog to block_truncate_page but does use get_xip_page | 401 | * functionality is analog to block_truncate_page but does use get_xip_mem |
402 | * to get the page instead of page cache | 402 | * to get the page instead of page cache |
403 | */ | 403 | */ |
404 | int | 404 | int |
@@ -408,9 +408,11 @@ xip_truncate_page(struct address_space *mapping, loff_t from) | |||
408 | unsigned offset = from & (PAGE_CACHE_SIZE-1); | 408 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
409 | unsigned blocksize; | 409 | unsigned blocksize; |
410 | unsigned length; | 410 | unsigned length; |
411 | struct page *page; | 411 | void *xip_mem; |
412 | unsigned long xip_pfn; | ||
413 | int err; | ||
412 | 414 | ||
413 | BUG_ON(!mapping->a_ops->get_xip_page); | 415 | BUG_ON(!mapping->a_ops->get_xip_mem); |
414 | 416 | ||
415 | blocksize = 1 << mapping->host->i_blkbits; | 417 | blocksize = 1 << mapping->host->i_blkbits; |
416 | length = offset & (blocksize - 1); | 418 | length = offset & (blocksize - 1); |
@@ -421,18 +423,16 @@ xip_truncate_page(struct address_space *mapping, loff_t from) | |||
421 | 423 | ||
422 | length = blocksize - length; | 424 | length = blocksize - length; |
423 | 425 | ||
424 | page = mapping->a_ops->get_xip_page(mapping, | 426 | err = mapping->a_ops->get_xip_mem(mapping, index, 0, |
425 | index*(PAGE_SIZE/512), 0); | 427 | &xip_mem, &xip_pfn); |
426 | if (!page) | 428 | if (unlikely(err)) { |
427 | return -ENOMEM; | 429 | if (err == -ENODATA) |
428 | if (unlikely(IS_ERR(page))) { | ||
429 | if (PTR_ERR(page) == -ENODATA) | ||
430 | /* Hole? No need to truncate */ | 430 | /* Hole? No need to truncate */ |
431 | return 0; | 431 | return 0; |
432 | else | 432 | else |
433 | return PTR_ERR(page); | 433 | return err; |
434 | } | 434 | } |
435 | zero_user(page, offset, length); | 435 | memset(xip_mem + offset, 0, length); |
436 | return 0; | 436 | return 0; |
437 | } | 437 | } |
438 | EXPORT_SYMBOL_GPL(xip_truncate_page); | 438 | EXPORT_SYMBOL_GPL(xip_truncate_page); |