Merge tag 'probes-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux...

[thirdparty/kernel/linux.git] / kernel / trace / trace_probe.c

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index c3f2937b434aa5bc5ae24d576a7e552dde2b3b46..5e263c14157403cd9ad65be5bf543fe525fb09ba 100644 (file)
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -12,6 +12,7 @@
 #define pr_fmt(fmt)    "trace_probe: " fmt
 
 #include <linux/bpf.h>
+#include <linux/fs.h>
 #include "trace_btf.h"
 
 #include "trace_probe.h"
@@ -1737,6 +1738,68 @@ error:
        return ERR_PTR(ret);
 }
 
+/* @buf: *buf must be equal to NULL. Caller must to free *buf */
+int traceprobe_expand_dentry_args(int argc, const char *argv[], char **buf)
+{
+       int i, used, ret;
+       const int bufsize = MAX_DENTRY_ARGS_LEN;
+       char *tmpbuf = NULL;
+
+       if (*buf)
+               return -EINVAL;
+
+       used = 0;
+       for (i = 0; i < argc; i++) {
+               char *tmp;
+               char *equal;
+               size_t arg_len;
+
+               if (!glob_match("*:%p[dD]", argv[i]))
+                       continue;
+
+               if (!tmpbuf) {
+                       tmpbuf = kmalloc(bufsize, GFP_KERNEL);
+                       if (!tmpbuf)
+                               return -ENOMEM;
+               }
+
+               tmp = kstrdup(argv[i], GFP_KERNEL);
+               if (!tmp)
+                       goto nomem;
+
+               equal = strchr(tmp, '=');
+               if (equal)
+                       *equal = '\0';
+               arg_len = strlen(argv[i]);
+               tmp[arg_len - 4] = '\0';
+               if (argv[i][arg_len - 1] == 'd')
+                       ret = snprintf(tmpbuf + used, bufsize - used,
+                                      "%s%s+0x0(+0x%zx(%s)):string",
+                                      equal ? tmp : "", equal ? "=" : "",
+                                      offsetof(struct dentry, d_name.name),
+                                      equal ? equal + 1 : tmp);
+               else
+                       ret = snprintf(tmpbuf + used, bufsize - used,
+                                      "%s%s+0x0(+0x%zx(+0x%zx(%s))):string",
+                                      equal ? tmp : "", equal ? "=" : "",
+                                      offsetof(struct dentry, d_name.name),
+                                      offsetof(struct file, f_path.dentry),
+                                      equal ? equal + 1 : tmp);
+
+               kfree(tmp);
+               if (ret >= bufsize - used)
+                       goto nomem;
+               argv[i] = tmpbuf + used;
+               used += ret + 1;
+       }
+
+       *buf = tmpbuf;
+       return 0;
+nomem:
+       kfree(tmpbuf);
+       return -ENOMEM;
+}
+
 void traceprobe_finish_parse(struct traceprobe_parse_context *ctx)
 {
        clear_btf_context(ctx);