{"id":1418,"date":"2018-06-20T15:36:20","date_gmt":"2018-06-20T07:36:20","guid":{"rendered":"https:\/\/damogame.cn:15443\/wordpress\/?p=1418"},"modified":"2018-06-20T15:36:20","modified_gmt":"2018-06-20T07:36:20","slug":"%e8%ae%a4%e7%9c%9f%e5%88%86%e6%9e%90mmap%ef%bc%9a%e6%98%af%e4%bb%80%e4%b9%88-%e4%b8%ba%e4%bb%80%e4%b9%88-%e6%80%8e%e4%b9%88%e7%94%a8","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/1418","title":{"rendered":"\u8ba4\u771f\u5206\u6790mmap\uff1a\u662f\u4ec0\u4e48 \u4e3a\u4ec0\u4e48 \u600e\u4e48\u7528"},"content":{"rendered":"<h1 class=\"postTitle\"><a id=\"cb_post_title_url\" class=\"postTitle2\" href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html\">\u8ba4\u771f\u5206\u6790mmap\uff1a\u662f\u4ec0\u4e48 \u4e3a\u4ec0\u4e48 \u600e\u4e48\u7528<\/a><\/h1>\n<div class=\"clear\"><\/div>\n<div class=\"postBody\">\n<div id=\"cnblogs_post_body\" class=\"blogpost-body\"><a name=\"_labelTop\"><\/a><\/p>\n<div id=\"navCategory\">\n<p><b>\u9605\u8bfb\u76ee\u5f55<\/b><\/p>\n<ul>\n<li><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_label0\">mmap\u57fa\u7840\u6982\u5ff5<\/a><\/li>\n<li><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_label1\">mmap\u5185\u5b58\u6620\u5c04\u539f\u7406<\/a><\/li>\n<li><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_label2\">mmap\u548c\u5e38\u89c4\u6587\u4ef6\u64cd\u4f5c\u7684\u533a\u522b<\/a><\/li>\n<li><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_label3\">mmap\u4f18\u70b9\u603b\u7ed3<\/a><\/li>\n<li><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_label4\">mmap\u76f8\u5173\u51fd\u6570<\/a><\/li>\n<li><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_label5\">mmap\u4f7f\u7528\u7ec6\u8282<\/a><\/li>\n<\/ul>\n<\/div>\n<div><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_labelTop\">\u56de\u5230\u9876\u90e8<\/a><a name=\"_label0\"><\/a><\/div>\n<h1>mmap\u57fa\u7840\u6982\u5ff5<\/h1>\n<p>mmap\u662f\u4e00\u79cd\u5185\u5b58\u6620\u5c04\u6587\u4ef6\u7684\u65b9\u6cd5\uff0c\u5373\u5c06\u4e00\u4e2a\u6587\u4ef6\u6216\u8005\u5176\u5b83\u5bf9\u8c61\u6620\u5c04\u5230\u8fdb\u7a0b\u7684\u5730\u5740\u7a7a\u95f4\uff0c\u5b9e\u73b0\u6587\u4ef6\u78c1\u76d8\u5730\u5740\u548c\u8fdb\u7a0b\u865a\u62df\u5730\u5740\u7a7a\u95f4\u4e2d\u4e00\u6bb5\u865a\u62df\u5730\u5740\u7684\u4e00\u4e00\u5bf9\u6620\u5173\u7cfb\u3002\u5b9e\u73b0\u8fd9\u6837\u7684\u6620\u5c04\u5173\u7cfb\u540e\uff0c\u8fdb\u7a0b\u5c31\u53ef\u4ee5\u91c7\u7528\u6307\u9488\u7684\u65b9\u5f0f\u8bfb\u5199\u64cd\u4f5c\u8fd9\u4e00\u6bb5\u5185\u5b58\uff0c\u800c\u7cfb\u7edf\u4f1a\u81ea\u52a8\u56de\u5199\u810f\u9875\u9762\u5230\u5bf9\u5e94\u7684\u6587\u4ef6\u78c1\u76d8\u4e0a\uff0c\u5373\u5b8c\u6210\u4e86\u5bf9\u6587\u4ef6\u7684\u64cd\u4f5c\u800c\u4e0d\u5fc5\u518d\u8c03\u7528read,write\u7b49\u7cfb\u7edf\u8c03\u7528\u51fd\u6570\u3002\u76f8\u53cd\uff0c\u5185\u6838\u7a7a\u95f4\u5bf9\u8fd9\u6bb5\u533a\u57df\u7684\u4fee\u6539\u4e5f\u76f4\u63a5\u53cd\u6620\u7528\u6237\u7a7a\u95f4\uff0c\u4ece\u800c\u53ef\u4ee5\u5b9e\u73b0\u4e0d\u540c\u8fdb\u7a0b\u95f4\u7684\u6587\u4ef6\u5171\u4eab\u3002\u5982\u4e0b\u56fe\u6240\u793a\uff1a<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/images0.cnblogs.com\/blog2015\/571793\/201507\/200501092691998.png\" alt=\"\" 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decoding=\"async\" src=\"https:\/\/images0.cnblogs.com\/blog2015\/571793\/201507\/200501434261629.png\" alt=\"\" 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href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_labelTop\">\u56de\u5230\u9876\u90e8<\/a><a name=\"_label1\"><\/a><\/div>\n<h1><span lang=\"EN-US\">mmap\u5185\u5b58\u6620\u5c04\u539f\u7406<\/span><\/h1>\n<p>mmap\u5185\u5b58\u6620\u5c04\u7684\u5b9e\u73b0\u8fc7\u7a0b\uff0c\u603b\u7684\u6765\u8bf4\u53ef\u4ee5\u5206\u4e3a\u4e09\u4e2a\u9636\u6bb5\uff1a<\/p>\n<p><strong>\uff08\u4e00\uff09\u8fdb\u7a0b\u542f\u52a8\u6620\u5c04\u8fc7\u7a0b\uff0c\u5e76\u5728\u865a\u62df\u5730\u5740\u7a7a\u95f4\u4e2d\u4e3a\u6620\u5c04\u521b\u5efa\u865a\u62df\u6620\u5c04\u533a\u57df<\/strong><\/p>\n<p class=\"p0\">1\u3001\u8fdb\u7a0b\u5728\u7528\u6237\u7a7a\u95f4\u8c03\u7528\u5e93\u51fd\u6570mmap\uff0c\u539f\u578b\uff1avoid\u00a0*mmap(void\u00a0*start,\u00a0size_t\u00a0length,\u00a0int\u00a0prot,\u00a0int\u00a0flags, int\u00a0fd,\u00a0off_t\u00a0offset);<\/p>\n<p>2\u3001\u5728\u5f53\u524d\u8fdb\u7a0b\u7684\u865a\u62df\u5730\u5740\u7a7a\u95f4\u4e2d\uff0c\u5bfb\u627e\u4e00\u6bb5\u7a7a\u95f2\u7684\u6ee1\u8db3\u8981\u6c42\u7684\u8fde\u7eed\u7684\u865a\u62df\u5730\u5740<\/p>\n<p>3\u3001\u4e3a\u6b64\u865a\u62df\u533a\u5206\u914d\u4e00\u4e2avm_area_struct\u7ed3\u6784\uff0c\u63a5\u7740\u5bf9\u8fd9\u4e2a\u7ed3\u6784\u7684\u5404\u4e2a\u57df\u8fdb\u884c\u4e86\u521d\u59cb\u5316<\/p>\n<p>4\u3001\u5c06\u65b0\u5efa\u7684\u865a\u62df\u533a\u7ed3\u6784\uff08vm_area_struct\uff09\u63d2\u5165\u8fdb\u7a0b\u7684\u865a\u62df\u5730\u5740\u533a\u57df\u94fe\u8868\u6216\u6811\u4e2d<\/p>\n<p>&nbsp;<\/p>\n<p><strong>\uff08\u4e8c\uff09\u8c03\u7528\u5185\u6838\u7a7a\u95f4\u7684\u7cfb\u7edf\u8c03\u7528\u51fd\u6570mmap\uff08\u4e0d\u540c\u4e8e\u7528\u6237\u7a7a\u95f4\u51fd\u6570\uff09\uff0c\u5b9e\u73b0\u6587\u4ef6\u7269\u7406\u5730\u5740\u548c\u8fdb\u7a0b\u865a\u62df\u5730\u5740\u7684\u4e00\u4e00\u6620\u5c04\u5173\u7cfb<\/strong><\/p>\n<p>5\u3001\u4e3a\u6620\u5c04\u5206\u914d\u4e86\u65b0\u7684\u865a\u62df\u5730\u5740\u533a\u57df\u540e\uff0c\u901a\u8fc7\u5f85\u6620\u5c04\u7684\u6587\u4ef6\u6307\u9488\uff0c\u5728\u6587\u4ef6\u63cf\u8ff0\u7b26\u8868\u4e2d\u627e\u5230\u5bf9\u5e94\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u901a\u8fc7\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u94fe\u63a5\u5230\u5185\u6838\u201c\u5df2\u6253\u5f00\u6587\u4ef6\u96c6\u201d\u4e2d\u8be5\u6587\u4ef6\u7684\u6587\u4ef6\u7ed3\u6784\u4f53\uff08struct file\uff09\uff0c\u6bcf\u4e2a\u6587\u4ef6\u7ed3\u6784\u4f53\u7ef4\u62a4\u7740\u548c\u8fd9\u4e2a\u5df2\u6253\u5f00\u6587\u4ef6\u76f8\u5173\u5404\u9879\u4fe1\u606f\u3002<\/p>\n<p>6\u3001\u901a\u8fc7\u8be5\u6587\u4ef6\u7684\u6587\u4ef6\u7ed3\u6784\u4f53\uff0c\u94fe\u63a5\u5230file_operations\u6a21\u5757\uff0c\u8c03\u7528\u5185\u6838\u51fd\u6570mmap\uff0c\u5176\u539f\u578b\u4e3a\uff1aint mmap(struct\u00a0file\u00a0*filp,\u00a0struct\u00a0vm_area_struct\u00a0*vma)\uff0c\u4e0d\u540c\u4e8e\u7528\u6237\u7a7a\u95f4\u5e93\u51fd\u6570\u3002<\/p>\n<p>7\u3001\u5185\u6838mmap\u51fd\u6570\u901a\u8fc7\u865a\u62df\u6587\u4ef6\u7cfb\u7edfinode\u6a21\u5757\u5b9a\u4f4d\u5230\u6587\u4ef6\u78c1\u76d8\u7269\u7406\u5730\u5740\u3002<\/p>\n<p>8\u3001\u901a\u8fc7remap_pfn_range\u51fd\u6570\u5efa\u7acb\u9875\u8868\uff0c\u5373\u5b9e\u73b0\u4e86\u6587\u4ef6\u5730\u5740\u548c\u865a\u62df\u5730\u5740\u533a\u57df\u7684\u6620\u5c04\u5173\u7cfb\u3002\u6b64\u65f6\uff0c\u8fd9\u7247\u865a\u62df\u5730\u5740\u5e76\u6ca1\u6709\u4efb\u4f55\u6570\u636e\u5173\u8054\u5230\u4e3b\u5b58\u4e2d\u3002<\/p>\n<p>&nbsp;<\/p>\n<p><strong>\uff08\u4e09\uff09\u8fdb\u7a0b\u53d1\u8d77\u5bf9\u8fd9\u7247\u6620\u5c04\u7a7a\u95f4\u7684\u8bbf\u95ee\uff0c\u5f15\u53d1\u7f3a\u9875\u5f02\u5e38\uff0c\u5b9e\u73b0\u6587\u4ef6\u5185\u5bb9\u5230\u7269\u7406\u5185\u5b58\uff08\u4e3b\u5b58\uff09\u7684\u62f7\u8d1d<\/strong><\/p>\n<p>\u6ce8\uff1a\u524d\u4e24\u4e2a\u9636\u6bb5\u4ec5\u5728\u4e8e\u521b\u5efa\u865a\u62df\u533a\u95f4\u5e76\u5b8c\u6210\u5730\u5740\u6620\u5c04\uff0c\u4f46\u662f\u5e76\u6ca1\u6709\u5c06\u4efb\u4f55\u6587\u4ef6\u6570\u636e\u7684\u62f7\u8d1d\u81f3\u4e3b\u5b58\u3002\u771f\u6b63\u7684\u6587\u4ef6\u8bfb\u53d6\u662f\u5f53\u8fdb\u7a0b\u53d1\u8d77\u8bfb\u6216\u5199\u64cd\u4f5c\u65f6\u3002<\/p>\n<p>9\u3001\u8fdb\u7a0b\u7684\u8bfb\u6216\u5199\u64cd\u4f5c\u8bbf\u95ee\u865a\u62df\u5730\u5740\u7a7a\u95f4\u8fd9\u4e00\u6bb5\u6620\u5c04\u5730\u5740\uff0c\u901a\u8fc7\u67e5\u8be2\u9875\u8868\uff0c\u53d1\u73b0\u8fd9\u4e00\u6bb5\u5730\u5740\u5e76\u4e0d\u5728\u7269\u7406\u9875\u9762\u4e0a\u3002\u56e0\u4e3a\u76ee\u524d\u53ea\u5efa\u7acb\u4e86\u5730\u5740\u6620\u5c04\uff0c\u771f\u6b63\u7684\u786c\u76d8\u6570\u636e\u8fd8\u6ca1\u6709\u62f7\u8d1d\u5230\u5185\u5b58\u4e2d\uff0c\u56e0\u6b64\u5f15\u53d1\u7f3a\u9875\u5f02\u5e38\u3002<\/p>\n<p>10\u3001\u7f3a\u9875\u5f02\u5e38\u8fdb\u884c\u4e00\u7cfb\u5217\u5224\u65ad\uff0c\u786e\u5b9a\u65e0\u975e\u6cd5\u64cd\u4f5c\u540e\uff0c\u5185\u6838\u53d1\u8d77\u8bf7\u6c42\u8c03\u9875\u8fc7\u7a0b\u3002<\/p>\n<p>11\u3001\u8c03\u9875\u8fc7\u7a0b\u5148\u5728\u4ea4\u6362\u7f13\u5b58\u7a7a\u95f4\uff08swap\u00a0cache\uff09\u4e2d\u5bfb\u627e\u9700\u8981\u8bbf\u95ee\u7684\u5185\u5b58\u9875\uff0c\u5982\u679c\u6ca1\u6709\u5219\u8c03\u7528nopage\u51fd\u6570\u628a\u6240\u7f3a\u7684\u9875\u4ece\u78c1\u76d8\u88c5\u5165\u5230\u4e3b\u5b58\u4e2d\u3002<\/p>\n<p>12\u3001\u4e4b\u540e\u8fdb\u7a0b\u5373\u53ef\u5bf9\u8fd9\u7247\u4e3b\u5b58\u8fdb\u884c\u8bfb\u6216\u8005\u5199\u7684\u64cd\u4f5c\uff0c\u5982\u679c\u5199\u64cd\u4f5c\u6539\u53d8\u4e86\u5176\u5185\u5bb9\uff0c\u4e00\u5b9a\u65f6\u95f4\u540e\u7cfb\u7edf\u4f1a\u81ea\u52a8\u56de\u5199\u810f\u9875\u9762\u5230\u5bf9\u5e94\u78c1\u76d8\u5730\u5740\uff0c\u4e5f\u5373\u5b8c\u6210\u4e86\u5199\u5165\u5230\u6587\u4ef6\u7684\u8fc7\u7a0b\u3002<\/p>\n<p>\u6ce8\uff1a\u4fee\u6539\u8fc7\u7684\u810f\u9875\u9762\u5e76\u4e0d\u4f1a\u7acb\u5373\u66f4\u65b0\u56de\u6587\u4ef6\u4e2d\uff0c\u800c\u662f\u6709\u4e00\u6bb5\u65f6\u95f4\u7684\u5ef6\u8fdf\uff0c\u53ef\u4ee5\u8c03\u7528msync()\u6765\u5f3a\u5236\u540c\u6b65, \u8fd9\u6837\u6240\u5199\u7684\u5185\u5bb9\u5c31\u80fd\u7acb\u5373\u4fdd\u5b58\u5230\u6587\u4ef6\u91cc\u4e86\u3002<\/p>\n<p>&nbsp;<\/p>\n<div><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_labelTop\">\u56de\u5230\u9876\u90e8<\/a><a name=\"_label2\"><\/a><\/div>\n<h1>mmap\u548c\u5e38\u89c4\u6587\u4ef6\u64cd\u4f5c\u7684\u533a\u522b<\/h1>\n<p>\u5bf9linux\u6587\u4ef6\u7cfb\u7edf\u4e0d\u4e86\u89e3\u7684\u670b\u53cb\uff0c\u8bf7\u53c2\u9605\u6211\u4e4b\u524d\u5199\u7684\u535a\u6587\u300a<a href=\"http:\/\/www.cnblogs.com\/huxiao-tee\/p\/4657851.html\" target=\"_blank\" rel=\"noopener\">\u4ece\u5185\u6838\u6587\u4ef6\u7cfb\u7edf\u770b\u6587\u4ef6\u8bfb\u5199\u8fc7\u7a0b<\/a>\u300b\uff0c\u6211\u4eec\u9996\u5148\u7b80\u5355\u7684\u56de\u987e\u4e00\u4e0b\u5e38\u89c4\u6587\u4ef6\u7cfb\u7edf\u64cd\u4f5c\uff08\u8c03\u7528read\/fread\u7b49\u7c7b\u51fd\u6570\uff09\u4e2d\uff0c\u51fd\u6570\u7684\u8c03\u7528\u8fc7\u7a0b\uff1a<\/p>\n<p>1\u3001\u8fdb\u7a0b\u53d1\u8d77\u8bfb\u6587\u4ef6\u8bf7\u6c42\u3002<\/p>\n<p>2\u3001\u5185\u6838\u901a\u8fc7\u67e5\u627e\u8fdb\u7a0b\u6587\u4ef6\u7b26\u8868\uff0c\u5b9a\u4f4d\u5230\u5185\u6838\u5df2\u6253\u5f00\u6587\u4ef6\u96c6\u4e0a\u7684\u6587\u4ef6\u4fe1\u606f\uff0c\u4ece\u800c\u627e\u5230\u6b64\u6587\u4ef6\u7684inode\u3002<\/p>\n<p>3\u3001inode\u5728address_space\u4e0a\u67e5\u627e\u8981\u8bf7\u6c42\u7684\u6587\u4ef6\u9875\u662f\u5426\u5df2\u7ecf\u7f13\u5b58\u5728\u9875\u7f13\u5b58\u4e2d\u3002\u5982\u679c\u5b58\u5728\uff0c\u5219\u76f4\u63a5\u8fd4\u56de\u8fd9\u7247\u6587\u4ef6\u9875\u7684\u5185\u5bb9\u3002<\/p>\n<p>4\u3001\u5982\u679c\u4e0d\u5b58\u5728\uff0c\u5219\u901a\u8fc7inode\u5b9a\u4f4d\u5230\u6587\u4ef6\u78c1\u76d8\u5730\u5740\uff0c\u5c06\u6570\u636e\u4ece\u78c1\u76d8\u590d\u5236\u5230\u9875\u7f13\u5b58\u3002\u4e4b\u540e\u518d\u6b21\u53d1\u8d77\u8bfb\u9875\u9762\u8fc7\u7a0b\uff0c\u8fdb\u800c\u5c06\u9875\u7f13\u5b58\u4e2d\u7684\u6570\u636e\u53d1\u7ed9\u7528\u6237\u8fdb\u7a0b\u3002<\/p>\n<p>\u603b\u7ed3\u6765\u8bf4\uff0c\u5e38\u89c4\u6587\u4ef6\u64cd\u4f5c\u4e3a\u4e86\u63d0\u9ad8\u8bfb\u5199\u6548\u7387\u548c\u4fdd\u62a4\u78c1\u76d8\uff0c\u4f7f\u7528\u4e86\u9875\u7f13\u5b58\u673a\u5236\u3002\u8fd9\u6837\u9020\u6210\u8bfb\u6587\u4ef6\u65f6\u9700\u8981\u5148\u5c06\u6587\u4ef6\u9875\u4ece\u78c1\u76d8\u62f7\u8d1d\u5230\u9875\u7f13\u5b58\u4e2d\uff0c\u7531\u4e8e\u9875\u7f13\u5b58\u5904\u5728\u5185\u6838\u7a7a\u95f4\uff0c\u4e0d\u80fd\u88ab\u7528\u6237\u8fdb\u7a0b\u76f4\u63a5\u5bfb\u5740\uff0c\u6240\u4ee5\u8fd8\u9700\u8981\u5c06\u9875\u7f13\u5b58\u4e2d\u6570\u636e\u9875\u518d\u6b21\u62f7\u8d1d\u5230\u5185\u5b58\u5bf9\u5e94\u7684\u7528\u6237\u7a7a\u95f4\u4e2d\u3002\u8fd9\u6837\uff0c\u901a\u8fc7\u4e86\u4e24\u6b21\u6570\u636e\u62f7\u8d1d\u8fc7\u7a0b\uff0c\u624d\u80fd\u5b8c\u6210\u8fdb\u7a0b\u5bf9\u6587\u4ef6\u5185\u5bb9\u7684\u83b7\u53d6\u4efb\u52a1\u3002\u5199\u64cd\u4f5c\u4e5f\u662f\u4e00\u6837\uff0c\u5f85\u5199\u5165\u7684buffer\u5728\u5185\u6838\u7a7a\u95f4\u4e0d\u80fd\u76f4\u63a5\u8bbf\u95ee\uff0c\u5fc5\u987b\u8981\u5148\u62f7\u8d1d\u81f3\u5185\u6838\u7a7a\u95f4\u5bf9\u5e94\u7684\u4e3b\u5b58\uff0c\u518d\u5199\u56de\u78c1\u76d8\u4e2d\uff08\u5ef6\u8fdf\u5199\u56de\uff09\uff0c\u4e5f\u662f\u9700\u8981\u4e24\u6b21\u6570\u636e\u62f7\u8d1d\u3002<\/p>\n<p>\u800c\u4f7f\u7528mmap\u64cd\u4f5c\u6587\u4ef6\u4e2d\uff0c\u521b\u5efa\u65b0\u7684\u865a\u62df\u5185\u5b58\u533a\u57df\u548c\u5efa\u7acb\u6587\u4ef6\u78c1\u76d8\u5730\u5740\u548c\u865a\u62df\u5185\u5b58\u533a\u57df\u6620\u5c04\u8fd9\u4e24\u6b65\uff0c\u6ca1\u6709\u4efb\u4f55\u6587\u4ef6\u62f7\u8d1d\u64cd\u4f5c\u3002\u800c\u4e4b\u540e\u8bbf\u95ee\u6570\u636e\u65f6\u53d1\u73b0\u5185\u5b58\u4e2d\u5e76\u65e0\u6570\u636e\u800c\u53d1\u8d77\u7684\u7f3a\u9875\u5f02\u5e38\u8fc7\u7a0b\uff0c\u53ef\u4ee5\u901a\u8fc7\u5df2\u7ecf\u5efa\u7acb\u597d\u7684\u6620\u5c04\u5173\u7cfb\uff0c\u53ea\u4f7f\u7528\u4e00\u6b21\u6570\u636e\u62f7\u8d1d\uff0c\u5c31\u4ece\u78c1\u76d8\u4e2d\u5c06\u6570\u636e\u4f20\u5165\u5185\u5b58\u7684\u7528\u6237\u7a7a\u95f4\u4e2d\uff0c\u4f9b\u8fdb\u7a0b\u4f7f\u7528\u3002<\/p>\n<p><strong>\u603b\u800c\u8a00\u4e4b\uff0c\u5e38\u89c4\u6587\u4ef6\u64cd\u4f5c\u9700\u8981\u4ece\u78c1\u76d8\u5230\u9875\u7f13\u5b58\u518d\u5230\u7528\u6237\u4e3b\u5b58\u7684\u4e24\u6b21\u6570\u636e\u62f7\u8d1d\u3002\u800cmmap\u64cd\u63a7\u6587\u4ef6\uff0c\u53ea\u9700\u8981\u4ece\u78c1\u76d8\u5230\u7528\u6237\u4e3b\u5b58\u7684\u4e00\u6b21\u6570\u636e\u62f7\u8d1d\u8fc7\u7a0b\u3002<\/strong>\u8bf4\u767d\u4e86\uff0cmmap\u7684\u5173\u952e\u70b9\u662f\u5b9e\u73b0\u4e86\u7528\u6237\u7a7a\u95f4\u548c\u5185\u6838\u7a7a\u95f4\u7684\u6570\u636e\u76f4\u63a5\u4ea4\u4e92\u800c\u7701\u53bb\u4e86\u7a7a\u95f4\u4e0d\u540c\u6570\u636e\u4e0d\u901a\u7684\u7e41\u7410\u8fc7\u7a0b\u3002\u56e0\u6b64mmap\u6548\u7387\u66f4\u9ad8\u3002<\/p>\n<p>&nbsp;<\/p>\n<div><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_labelTop\">\u56de\u5230\u9876\u90e8<\/a><a name=\"_label3\"><\/a><\/div>\n<h1>mmap\u4f18\u70b9\u603b\u7ed3<\/h1>\n<p>\u7531\u4e0a\u6587\u8ba8\u8bba\u53ef\u77e5\uff0cmmap\u4f18\u70b9\u5171\u6709\u4e00\u4e0b\u51e0\u70b9\uff1a<\/p>\n<p>1\u3001\u5bf9\u6587\u4ef6\u7684\u8bfb\u53d6\u64cd\u4f5c\u8de8\u8fc7\u4e86\u9875\u7f13\u5b58\uff0c\u51cf\u5c11\u4e86\u6570\u636e\u7684\u62f7\u8d1d\u6b21\u6570\uff0c\u7528\u5185\u5b58\u8bfb\u5199\u53d6\u4ee3I\/O\u8bfb\u5199\uff0c\u63d0\u9ad8\u4e86\u6587\u4ef6\u8bfb\u53d6\u6548\u7387\u3002<\/p>\n<p>2\u3001\u5b9e\u73b0\u4e86\u7528\u6237\u7a7a\u95f4\u548c\u5185\u6838\u7a7a\u95f4\u7684\u9ad8\u6548\u4ea4\u4e92\u65b9\u5f0f\u3002\u4e24\u7a7a\u95f4\u7684\u5404\u81ea\u4fee\u6539\u64cd\u4f5c\u53ef\u4ee5\u76f4\u63a5\u53cd\u6620\u5728\u6620\u5c04\u7684\u533a\u57df\u5185\uff0c\u4ece\u800c\u88ab\u5bf9\u65b9\u7a7a\u95f4\u53ca\u65f6\u6355\u6349\u3002<\/p>\n<p>3\u3001\u63d0\u4f9b\u8fdb\u7a0b\u95f4\u5171\u4eab\u5185\u5b58\u53ca\u76f8\u4e92\u901a\u4fe1\u7684\u65b9\u5f0f\u3002\u4e0d\u7ba1\u662f\u7236\u5b50\u8fdb\u7a0b\u8fd8\u662f\u65e0\u4eb2\u7f18\u5173\u7cfb\u7684\u8fdb\u7a0b\uff0c\u90fd\u53ef\u4ee5\u5c06\u81ea\u8eab\u7528\u6237\u7a7a\u95f4\u6620\u5c04\u5230\u540c\u4e00\u4e2a\u6587\u4ef6\u6216\u533f\u540d\u6620\u5c04\u5230\u540c\u4e00\u7247\u533a\u57df\u3002\u4ece\u800c\u901a\u8fc7\u5404\u81ea\u5bf9\u6620\u5c04\u533a\u57df\u7684\u6539\u52a8\uff0c\u8fbe\u5230\u8fdb\u7a0b\u95f4\u901a\u4fe1\u548c\u8fdb\u7a0b\u95f4\u5171\u4eab\u7684\u76ee\u7684\u3002<\/p>\n<p>\u540c\u65f6\uff0c\u5982\u679c\u8fdb\u7a0bA\u548c\u8fdb\u7a0bB\u90fd\u6620\u5c04\u4e86\u533a\u57dfC\uff0c\u5f53A\u7b2c\u4e00\u6b21\u8bfb\u53d6C\u65f6\u901a\u8fc7\u7f3a\u9875\u4ece\u78c1\u76d8\u590d\u5236\u6587\u4ef6\u9875\u5230\u5185\u5b58\u4e2d\uff1b\u4f46\u5f53B\u518d\u8bfbC\u7684\u76f8\u540c\u9875\u9762\u65f6\uff0c\u867d\u7136\u4e5f\u4f1a\u4ea7\u751f\u7f3a\u9875\u5f02\u5e38\uff0c\u4f46\u662f\u4e0d\u518d\u9700\u8981\u4ece\u78c1\u76d8\u4e2d\u590d\u5236\u6587\u4ef6\u8fc7\u6765\uff0c\u800c\u53ef\u76f4\u63a5\u4f7f\u7528\u5df2\u7ecf\u4fdd\u5b58\u5728\u5185\u5b58\u4e2d\u7684\u6587\u4ef6\u6570\u636e\u3002<\/p>\n<p>4\u3001\u53ef\u7528\u4e8e\u5b9e\u73b0\u9ad8\u6548\u7684\u5927\u89c4\u6a21\u6570\u636e\u4f20\u8f93\u3002\u5185\u5b58\u7a7a\u95f4\u4e0d\u8db3\uff0c\u662f\u5236\u7ea6\u5927\u6570\u636e\u64cd\u4f5c\u7684\u4e00\u4e2a\u65b9\u9762\uff0c\u89e3\u51b3\u65b9\u6848\u5f80\u5f80\u662f\u501f\u52a9\u786c\u76d8\u7a7a\u95f4\u534f\u52a9\u64cd\u4f5c\uff0c\u8865\u5145\u5185\u5b58\u7684\u4e0d\u8db3\u3002\u4f46\u662f\u8fdb\u4e00\u6b65\u4f1a\u9020\u6210\u5927\u91cf\u7684\u6587\u4ef6I\/O\u64cd\u4f5c\uff0c\u6781\u5927\u5f71\u54cd\u6548\u7387\u3002\u8fd9\u4e2a\u95ee\u9898\u53ef\u4ee5\u901a\u8fc7mmap\u6620\u5c04\u5f88\u597d\u7684\u89e3\u51b3\u3002\u6362\u53e5\u8bdd\u8bf4\uff0c\u4f46\u51e1\u662f\u9700\u8981\u7528\u78c1\u76d8\u7a7a\u95f4\u4ee3\u66ff\u5185\u5b58\u7684\u65f6\u5019\uff0cmmap\u90fd\u53ef\u4ee5\u53d1\u6325\u5176\u529f\u6548\u3002<\/p>\n<p>&nbsp;<\/p>\n<div><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_labelTop\">\u56de\u5230\u9876\u90e8<\/a><a name=\"_label4\"><\/a><\/div>\n<h1>mmap\u76f8\u5173\u51fd\u6570<\/h1>\n<p><strong>\u51fd\u6570\u539f\u578b<\/strong><\/p>\n<p><span lang=\"EN-US\">void\u00a0*mmap(void\u00a0*start,\u00a0size_t\u00a0length,\u00a0int\u00a0prot,\u00a0int\u00a0flags,\u00a0int\u00a0fd,\u00a0off_t\u00a0offset);<\/span><\/p>\n<p><strong>\u8fd4\u56de\u8bf4\u660e<\/strong><\/p>\n<p class=\"p0\">\u6210\u529f\u6267\u884c\u65f6\uff0c<span lang=\"EN-US\">mmap()\u8fd4\u56de\u88ab\u6620\u5c04\u533a\u7684\u6307\u9488\u3002\u5931\u8d25\u65f6\uff0cmmap()\u8fd4\u56deMAP_FAILED[\u5176\u503c\u4e3a(void\u00a0*)-1]\uff0c\u00a0error\u88ab\u8bbe\u4e3a\u4ee5\u4e0b\u7684\u67d0\u4e2a\u503c\uff1a<\/span><\/p>\n<div class=\"cnblogs_code\"><img decoding=\"async\" id=\"code_img_closed_ede8fbfc-217b-429a-8fe9-a7d5bdc0e4aa\" class=\"code_img_closed\" src=\"https:\/\/images.cnblogs.com\/OutliningIndicators\/ContractedBlock.gif\" alt=\"\" \/>\u00a0<span class=\"cnblogs_code_collapse\">\u8fd4\u56de\u9519\u8bef\u7c7b\u578b<\/span><\/div>\n<p><strong>\u53c2\u6570<\/strong><\/p>\n<p class=\"p0\"><span lang=\"EN-US\">start\uff1a\u6620\u5c04\u533a\u7684\u5f00\u59cb\u5730\u5740<\/span><\/p>\n<p class=\"p0\"><span lang=\"EN-US\">length\uff1a\u6620\u5c04\u533a\u7684\u957f\u5ea6<\/span><\/p>\n<p class=\"p0\"><span lang=\"EN-US\">prot\uff1a\u671f\u671b\u7684\u5185\u5b58\u4fdd\u62a4\u6807\u5fd7\uff0c\u4e0d\u80fd\u4e0e\u6587\u4ef6\u7684\u6253\u5f00\u6a21\u5f0f\u51b2\u7a81\u3002\u662f\u4ee5\u4e0b\u7684\u67d0\u4e2a\u503c\uff0c\u53ef\u4ee5\u901a\u8fc7or\u8fd0\u7b97\u5408\u7406\u5730\u7ec4\u5408\u5728\u4e00\u8d77<\/span><\/p>\n<div class=\"cnblogs_code\"><img decoding=\"async\" id=\"code_img_closed_3b467440-f363-4d8b-8b2f-066a4283b92b\" class=\"code_img_closed\" src=\"https:\/\/images.cnblogs.com\/OutliningIndicators\/ContractedBlock.gif\" alt=\"\" \/>\u00a0<span class=\"cnblogs_code_collapse\">prot<\/span><\/div>\n<p class=\"p0\"><span lang=\"EN-US\">flags\uff1a\u6307\u5b9a\u6620\u5c04\u5bf9\u8c61\u7684\u7c7b\u578b\uff0c\u6620\u5c04\u9009\u9879\u548c\u6620\u5c04\u9875\u662f\u5426\u53ef\u4ee5\u5171\u4eab\u3002\u5b83\u7684\u503c\u53ef\u4ee5\u662f\u4e00\u4e2a\u6216\u8005\u591a\u4e2a\u4ee5\u4e0b\u4f4d\u7684\u7ec4\u5408\u4f53<\/span><\/p>\n<div class=\"cnblogs_code\"><img decoding=\"async\" id=\"code_img_closed_5df73eb8-18a9-484d-b82d-5875c2b921dc\" class=\"code_img_closed\" src=\"https:\/\/images.cnblogs.com\/OutliningIndicators\/ContractedBlock.gif\" alt=\"\" \/>\u00a0<span class=\"cnblogs_code_collapse\">flag<\/span><\/div>\n<p class=\"p0\"><span lang=\"EN-US\">fd\uff1a\u6709\u6548\u7684\u6587\u4ef6\u63cf\u8ff0\u8bcd\u3002\u5982\u679cMAP_ANONYMOUS\u88ab\u8bbe\u5b9a\uff0c\u4e3a\u4e86\u517c\u5bb9\u95ee\u9898\uff0c\u5176\u503c\u5e94\u4e3a-1<\/span><\/p>\n<p class=\"p0\"><span lang=\"EN-US\">offset\uff1a\u88ab\u6620\u5c04\u5bf9\u8c61\u5185\u5bb9\u7684\u8d77\u70b9<\/span><\/p>\n<p class=\"p0\"><strong>\u76f8\u5173\u51fd\u6570<\/strong><\/p>\n<p class=\"p0\"><span lang=\"EN-US\">int\u00a0munmap(\u00a0void\u00a0*\u00a0addr,\u00a0size_t\u00a0len\u00a0)\u00a0<\/span><\/p>\n<p class=\"p0\">\u6210\u529f\u6267\u884c\u65f6\uff0c<span lang=\"EN-US\">munmap()\u8fd4\u56de0\u3002\u5931\u8d25\u65f6\uff0cmunmap\u8fd4\u56de-1\uff0cerror\u8fd4\u56de\u6807\u5fd7\u548cmmap\u4e00\u81f4\uff1b<br \/>\n<\/span><\/p>\n<p class=\"p0\"><span lang=\"EN-US\">\u8be5\u8c03\u7528\u5728\u8fdb\u7a0b\u5730\u5740\u7a7a\u95f4\u4e2d\u89e3\u9664\u4e00\u4e2a\u6620\u5c04\u5173\u7cfb\uff0caddr\u662f\u8c03\u7528mmap()\u65f6\u8fd4\u56de\u7684\u5730\u5740\uff0clen\u662f\u6620\u5c04\u533a\u7684\u5927\u5c0f\uff1b<\/span><\/p>\n<p class=\"p0\"><span lang=\"EN-US\">\u5f53\u6620\u5c04\u5173\u7cfb\u89e3\u9664\u540e\uff0c\u5bf9\u539f\u6765\u6620\u5c04\u5730\u5740\u7684\u8bbf\u95ee\u5c06\u5bfc\u81f4\u6bb5\u9519\u8bef\u53d1\u751f\u3002\u00a0<\/span><\/p>\n<p class=\"p0\">\n<p class=\"p0\">int msync( void *addr, size_t len, int flags )<\/p>\n<p class=\"p0\"><span lang=\"EN-US\">\u4e00\u822c\u8bf4\u6765\uff0c\u8fdb\u7a0b\u5728\u6620\u5c04\u7a7a\u95f4\u7684\u5bf9\u5171\u4eab\u5185\u5bb9\u7684\u6539\u53d8\u5e76\u4e0d\u76f4\u63a5\u5199\u56de\u5230\u78c1\u76d8\u6587\u4ef6\u4e2d\uff0c\u5f80\u5f80\u5728\u8c03\u7528munmap\uff08\uff09\u540e\u624d\u6267\u884c\u8be5\u64cd\u4f5c\u3002<\/span><\/p>\n<p class=\"p0\"><span lang=\"EN-US\">\u53ef\u4ee5\u901a\u8fc7\u8c03\u7528msync()\u5b9e\u73b0\u78c1\u76d8\u4e0a\u6587\u4ef6\u5185\u5bb9\u4e0e\u5171\u4eab\u5185\u5b58\u533a\u7684\u5185\u5bb9\u4e00\u81f4\u3002<\/span><\/p>\n<p class=\"p0\">\n<div><a href=\"https:\/\/www.cnblogs.com\/huxiao-tee\/p\/4660352.html#_labelTop\">\u56de\u5230\u9876\u90e8<\/a><a name=\"_label5\"><\/a><\/div>\n<h1>mmap\u4f7f\u7528\u7ec6\u8282<\/h1>\n<p>1\u3001\u4f7f\u7528mmap\u9700\u8981\u6ce8\u610f\u7684\u4e00\u4e2a\u5173\u952e\u70b9\u662f\uff0cmmap\u6620\u5c04\u533a\u57df\u5927\u5c0f\u5fc5\u987b\u662f\u7269\u7406\u9875\u5927\u5c0f(page_size)\u7684\u6574\u500d\u6570\uff0832\u4f4d\u7cfb\u7edf\u4e2d\u901a\u5e38\u662f4k\u5b57\u8282\uff09\u3002\u539f\u56e0\u662f\uff0c\u5185\u5b58\u7684\u6700\u5c0f\u7c92\u5ea6\u662f\u9875\uff0c\u800c\u8fdb\u7a0b\u865a\u62df\u5730\u5740\u7a7a\u95f4\u548c\u5185\u5b58\u7684\u6620\u5c04\u4e5f\u662f\u4ee5\u9875\u4e3a\u5355\u4f4d\u3002\u4e3a\u4e86\u5339\u914d\u5185\u5b58\u7684\u64cd\u4f5c\uff0cmmap\u4ece\u78c1\u76d8\u5230\u865a\u62df\u5730\u5740\u7a7a\u95f4\u7684\u6620\u5c04\u4e5f\u5fc5\u987b\u662f\u9875\u3002<\/p>\n<p>2\u3001\u5185\u6838\u53ef\u4ee5\u8ddf\u8e2a\u88ab\u5185\u5b58\u6620\u5c04\u7684\u5e95\u5c42\u5bf9\u8c61\uff08\u6587\u4ef6\uff09\u7684\u5927\u5c0f\uff0c\u8fdb\u7a0b\u53ef\u4ee5\u5408\u6cd5\u7684\u8bbf\u95ee\u5728\u5f53\u524d\u6587\u4ef6\u5927\u5c0f\u4ee5\u5185\u53c8\u5728\u5185\u5b58\u6620\u5c04\u533a\u4ee5\u5185\u7684\u90a3\u4e9b\u5b57\u8282\u3002\u4e5f\u5c31\u662f\u8bf4\uff0c\u5982\u679c\u6587\u4ef6\u7684\u5927\u5c0f\u4e00\u76f4\u5728\u6269\u5f20\uff0c\u53ea\u8981\u5728\u6620\u5c04\u533a\u57df\u8303\u56f4\u5185\u7684\u6570\u636e\uff0c\u8fdb\u7a0b\u90fd\u53ef\u4ee5\u5408\u6cd5\u5f97\u5230\uff0c\u8fd9\u548c\u6620\u5c04\u5efa\u7acb\u65f6\u6587\u4ef6\u7684\u5927\u5c0f\u65e0\u5173\u3002\u5177\u4f53\u60c5\u5f62\u53c2\u89c1\u201c\u60c5\u5f62\u4e09\u201d\u3002<\/p>\n<p>3\u3001\u6620\u5c04\u5efa\u7acb\u4e4b\u540e\uff0c\u5373\u4f7f\u6587\u4ef6\u5173\u95ed\uff0c\u6620\u5c04\u4f9d\u7136\u5b58\u5728\u3002\u56e0\u4e3a\u6620\u5c04\u7684\u662f\u78c1\u76d8\u7684\u5730\u5740\uff0c\u4e0d\u662f\u6587\u4ef6\u672c\u8eab\uff0c\u548c\u6587\u4ef6\u53e5\u67c4\u65e0\u5173\u3002\u540c\u65f6\u53ef\u7528\u4e8e\u8fdb\u7a0b\u95f4\u901a\u4fe1\u7684\u6709\u6548\u5730\u5740\u7a7a\u95f4\u4e0d\u5b8c\u5168\u53d7\u9650\u4e8e\u88ab\u6620\u5c04\u6587\u4ef6\u7684\u5927\u5c0f\uff0c\u56e0\u4e3a\u662f\u6309\u9875\u6620\u5c04\u3002<\/p>\n<p>&nbsp;<\/p>\n<p>\u5728\u4e0a\u9762\u7684\u77e5\u8bc6\u524d\u63d0\u4e0b\uff0c\u6211\u4eec\u4e0b\u9762\u770b\u770b\u5982\u679c\u5927\u5c0f\u4e0d\u662f\u9875\u7684\u6574\u500d\u6570\u7684\u5177\u4f53\u60c5\u51b5\uff1a<\/p>\n<p><strong>\u60c5\u5f62\u4e00\uff1a\u4e00\u4e2a\u6587\u4ef6\u7684\u5927\u5c0f\u662f5000\u5b57\u8282\uff0cmmap\u51fd\u6570\u4ece\u4e00\u4e2a\u6587\u4ef6\u7684\u8d77\u59cb\u4f4d\u7f6e\u5f00\u59cb\uff0c\u6620\u5c045000\u5b57\u8282\u5230\u865a\u62df\u5185\u5b58\u4e2d\u3002<\/strong><\/p>\n<p>\u5206\u6790\uff1a\u56e0\u4e3a\u5355\u4f4d\u7269\u7406\u9875\u9762\u7684\u5927\u5c0f\u662f4096\u5b57\u8282\uff0c\u867d\u7136\u88ab\u6620\u5c04\u7684\u6587\u4ef6\u53ea\u67095000\u5b57\u8282\uff0c\u4f46\u662f\u5bf9\u5e94\u5230\u8fdb\u7a0b\u865a\u62df\u5730\u5740\u533a\u57df\u7684\u5927\u5c0f\u9700\u8981\u6ee1\u8db3\u6574\u9875\u5927\u5c0f\uff0c\u56e0\u6b64mmap\u51fd\u6570\u6267\u884c\u540e\uff0c\u5b9e\u9645\u6620\u5c04\u5230\u865a\u62df\u5185\u5b58\u533a\u57df8192\u4e2a 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loading=\"lazy\" decoding=\"async\" src=\"https:\/\/images0.cnblogs.com\/blog2015\/571793\/201507\/200522381763096.png\" alt=\"\" width=\"646\" height=\"231\" 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