[PATCH v2 4/7] tracing/probes: support '%pD' type for print struct file's name

[Ye Bin]

Similar to '%pD' for printk, use '%pD' for print struct file's name.

Signed-off-by: Ye Bin <yebi...@huawei.com>
---
 kernel/trace/trace_probe.c | 41 ++++++++++++++++++++++++--------------
 1 file changed, 26 insertions(+), 15 deletions(-)

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 1599c0c3e6b7..f9819625de58 100644
--- 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"
@@ -1572,28 +1573,38 @@ int traceprobe_expand_dentry_args(int argc, const char 
*argv[], char *buf,
 
        used = 0;
        for (i = 0; i < argc; i++) {
-               if (str_has_suffix(argv[i], ":%pd")) {
-                       char *tmp = kstrdup(argv[i], GFP_KERNEL);
-                       char *equal;
+               if (!str_has_suffix(argv[i], ":%pd") &&
+                   !str_has_suffix(argv[i], ":%pD"))
+                       continue;
 
-                       if (!tmp)
-                               return -ENOMEM;
+               char *tmp = kstrdup(argv[i], GFP_KERNEL);
+               char *equal;
+
+               if (!tmp)
+                       return -ENOMEM;
 
-                       equal = strchr(tmp, '=');
-                       if (equal)
-                               *equal = '\0';
-                       tmp[strlen(argv[i]) - 4] = '\0';
+               equal = strchr(tmp, '=');
+               if (equal)
+                       *equal = '\0';
+               tmp[strlen(argv[i]) - 4] = '\0';
+               if (argv[i][strlen(argv[i]) - 1] == 'd')
                        ret = snprintf(buf + used, bufsize - used,
                                       "%s%s+0x0(+0x%zx(%s)):string",
                                       equal ? tmp : "", equal ? "=" : "",
                                       offsetof(struct dentry, d_name.name),
                                       equal ? equal + 1 : tmp);
-                       kfree(tmp);
-                       if (ret >= bufsize - used)
-                               return -ENOMEM;
-                       argv[i] = buf + used;
-                       used += ret + 1;
-               }
+               else
+                       ret = snprintf(buf + 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)
+                       return -ENOMEM;
+               argv[i] = buf + used;
+               used += ret + 1;
        }
 
        return 0;
-- 
2.31.1