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-rw-r--r--mm/util.c111
1 files changed, 3 insertions, 108 deletions
diff --git a/mm/util.c b/mm/util.c
index d5ea733c5082..093c973f1697 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -16,9 +16,6 @@
16 16
17#include "internal.h" 17#include "internal.h"
18 18
19#define CREATE_TRACE_POINTS
20#include <trace/events/kmem.h>
21
22/** 19/**
23 * kstrdup - allocate space for and copy an existing string 20 * kstrdup - allocate space for and copy an existing string
24 * @s: the string to duplicate 21 * @s: the string to duplicate
@@ -112,97 +109,6 @@ void *memdup_user(const void __user *src, size_t len)
112} 109}
113EXPORT_SYMBOL(memdup_user); 110EXPORT_SYMBOL(memdup_user);
114 111
115static __always_inline void *__do_krealloc(const void *p, size_t new_size,
116 gfp_t flags)
117{
118 void *ret;
119 size_t ks = 0;
120
121 if (p)
122 ks = ksize(p);
123
124 if (ks >= new_size)
125 return (void *)p;
126
127 ret = kmalloc_track_caller(new_size, flags);
128 if (ret && p)
129 memcpy(ret, p, ks);
130
131 return ret;
132}
133
134/**
135 * __krealloc - like krealloc() but don't free @p.
136 * @p: object to reallocate memory for.
137 * @new_size: how many bytes of memory are required.
138 * @flags: the type of memory to allocate.
139 *
140 * This function is like krealloc() except it never frees the originally
141 * allocated buffer. Use this if you don't want to free the buffer immediately
142 * like, for example, with RCU.
143 */
144void *__krealloc(const void *p, size_t new_size, gfp_t flags)
145{
146 if (unlikely(!new_size))
147 return ZERO_SIZE_PTR;
148
149 return __do_krealloc(p, new_size, flags);
150
151}
152EXPORT_SYMBOL(__krealloc);
153
154/**
155 * krealloc - reallocate memory. The contents will remain unchanged.
156 * @p: object to reallocate memory for.
157 * @new_size: how many bytes of memory are required.
158 * @flags: the type of memory to allocate.
159 *
160 * The contents of the object pointed to are preserved up to the
161 * lesser of the new and old sizes. If @p is %NULL, krealloc()
162 * behaves exactly like kmalloc(). If @new_size is 0 and @p is not a
163 * %NULL pointer, the object pointed to is freed.
164 */
165void *krealloc(const void *p, size_t new_size, gfp_t flags)
166{
167 void *ret;
168
169 if (unlikely(!new_size)) {
170 kfree(p);
171 return ZERO_SIZE_PTR;
172 }
173
174 ret = __do_krealloc(p, new_size, flags);
175 if (ret && p != ret)
176 kfree(p);
177
178 return ret;
179}
180EXPORT_SYMBOL(krealloc);
181
182/**
183 * kzfree - like kfree but zero memory
184 * @p: object to free memory of
185 *
186 * The memory of the object @p points to is zeroed before freed.
187 * If @p is %NULL, kzfree() does nothing.
188 *
189 * Note: this function zeroes the whole allocated buffer which can be a good
190 * deal bigger than the requested buffer size passed to kmalloc(). So be
191 * careful when using this function in performance sensitive code.
192 */
193void kzfree(const void *p)
194{
195 size_t ks;
196 void *mem = (void *)p;
197
198 if (unlikely(ZERO_OR_NULL_PTR(mem)))
199 return;
200 ks = ksize(mem);
201 memset(mem, 0, ks);
202 kfree(mem);
203}
204EXPORT_SYMBOL(kzfree);
205
206/* 112/*
207 * strndup_user - duplicate an existing string from user space 113 * strndup_user - duplicate an existing string from user space
208 * @s: The string to duplicate 114 * @s: The string to duplicate
@@ -277,17 +183,14 @@ pid_t vm_is_stack(struct task_struct *task,
277 183
278 if (in_group) { 184 if (in_group) {
279 struct task_struct *t; 185 struct task_struct *t;
280 rcu_read_lock();
281 if (!pid_alive(task))
282 goto done;
283 186
284 t = task; 187 rcu_read_lock();
285 do { 188 for_each_thread(task, t) {
286 if (vm_is_stack_for_task(t, vma)) { 189 if (vm_is_stack_for_task(t, vma)) {
287 ret = t->pid; 190 ret = t->pid;
288 goto done; 191 goto done;
289 } 192 }
290 } while_each_thread(task, t); 193 }
291done: 194done:
292 rcu_read_unlock(); 195 rcu_read_unlock();
293 } 196 }
@@ -504,11 +407,3 @@ out_mm:
504out: 407out:
505 return res; 408 return res;
506} 409}
507
508/* Tracepoints definitions. */
509EXPORT_TRACEPOINT_SYMBOL(kmalloc);
510EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);
511EXPORT_TRACEPOINT_SYMBOL(kmalloc_node);
512EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc_node);
513EXPORT_TRACEPOINT_SYMBOL(kfree);
514EXPORT_TRACEPOINT_SYMBOL(kmem_cache_free);