Re: [PATCH v5 1/7] libcxl: Add debugfs path to CXL context

[Alison Schofield <alison.schofield@intel.com>]

On Mon, Dec 15, 2025 at 03:36:24PM -0600, Ben Cheatham wrote:
> Find the CXL debugfs mount point and add it to the CXL library context.
> This will be used by poison and procotol error library functions to
> access the information presented by the filesystem.
> 
> Signed-off-by: Ben Cheatham <Benjamin.Cheatham@amd.com>
> ---
>  cxl/lib/libcxl.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
> 
> diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
> index cafde1c..71eff6d 100644
> --- a/cxl/lib/libcxl.c
> +++ b/cxl/lib/libcxl.c
> @@ -8,6 +8,7 @@
>  #include <stdlib.h>
>  #include <dirent.h>
>  #include <unistd.h>
> +#include <mntent.h>
>  #include <sys/mman.h>
>  #include <sys/stat.h>
>  #include <sys/types.h>
> @@ -54,6 +55,7 @@ struct cxl_ctx {
>  	struct kmod_ctx *kmod_ctx;
>  	struct daxctl_ctx *daxctl_ctx;
>  	void *private_data;
> +	const char *debugfs;

Do you want this const?  Later we alloc and eventually free it.


>  };
>  
>  static void free_pmem(struct cxl_pmem *pmem)
> @@ -240,6 +242,28 @@ CXL_EXPORT void *cxl_get_private_data(struct cxl_ctx *ctx)
>  	return ctx->private_data;
>  }
>  
> +static const char* get_debugfs_dir(void)

drop const above?



> +{
> +	char *debugfs_dir = NULL;
> +	struct mntent *ent;
> +	FILE *mntf;
> +
> +	mntf = setmntent("/proc/mounts", "r");
> +	if (!mntf)
> +		return NULL;
> +
> +	while ((ent = getmntent(mntf)) != NULL) {
> +		if (!strcmp(ent->mnt_type, "debugfs")) {

include <string.h>


> +			debugfs_dir = calloc(strlen(ent->mnt_dir) + 1, 1);
> +			strcpy(debugfs_dir, ent->mnt_dir);

perhaps -
        debugfs_dir = strdup(ent->mnt_dir);




> +			break;
> +		}
> +	}
> +
> +	endmntent(mntf);
> +	return debugfs_dir;
> +}

snip