On Wed, Sep 21, 2022 at 02:02:42PM -0700, Dave Jiang wrote:
> Add helper function to detect that the bus is cxl based.
>
A couple of wonderings below about int vs bool usage.
Reviewed-by: Alison Schofield <alison.schofi...@intel.com>
> Signed-off-by: Dave Jiang <dave.ji...@intel.com>
> ---
> ndctl/lib/libndctl.c | 53
> ++++++++++++++++++++++++++++++++++++++++++++++++
> ndctl/lib/libndctl.sym | 1 +
> ndctl/lib/private.h | 1 +
> ndctl/libndctl.h | 1 +
> 4 files changed, 56 insertions(+)
>
> diff --git a/ndctl/lib/libndctl.c b/ndctl/lib/libndctl.c
> index ad54f0626510..10422e24d38b 100644
> --- a/ndctl/lib/libndctl.c
> +++ b/ndctl/lib/libndctl.c
> @@ -12,6 +12,7 @@
> #include <ctype.h>
> #include <fcntl.h>
> #include <dirent.h>
> +#include <libgen.h>
> #include <sys/stat.h>
> #include <sys/types.h>
> #include <sys/ioctl.h>
> @@ -876,6 +877,48 @@ static enum ndctl_fwa_method fwa_method_to_method(const
> char *fwa_method)
> return NDCTL_FWA_METHOD_RESET;
> }
>
> +static int is_ndbus_cxl(const char *ctl_base)
is_ndbus_cxl() sounds like a boolean function.
> +{
> + char *path, *ppath, *subsys;
> + char tmp_path[PATH_MAX];
> + int rc;
> +
> + /* get the real path of ctl_base */
> + path = realpath(ctl_base, NULL);
> + if (!path)
> + return -errno;
> +
> + /* setup to get the nd bridge device backing the ctl */
> + sprintf(tmp_path, "%s/device", path);
> + free(path);
> +
> + path = realpath(tmp_path, NULL);
> + if (!path)
> + return -errno;
> +
> + /* get the parent dir of the ndbus, which should be the nvdimm-bridge */
> + ppath = dirname(path);
> +
> + /* setup to get the subsystem of the nvdimm-bridge */
> + sprintf(tmp_path, "%s/%s", ppath, "subsystem");
> + free(path);
> +
> + path = realpath(tmp_path, NULL);
> + if (!path)
> + return -errno;
> +
> + subsys = basename(path);
> +
> + /* check if subsystem is cxl */
> + if (!strcmp(subsys, "cxl"))
> + rc = 1;
> + else
> + rc = 0;
> +
> + free(path);
> + return rc;
> +}
> +
> static void *add_bus(void *parent, int id, const char *ctl_base)
> {
> char buf[SYSFS_ATTR_SIZE];
> @@ -919,6 +962,11 @@ static void *add_bus(void *parent, int id, const char
> *ctl_base)
> else
> bus->has_of_node = 1;
>
> + if (is_ndbus_cxl(ctl_base))
> + bus->has_cxl = 1;
> + else
> + bus->has_cxl = 0;
> +
> sprintf(path, "%s/device/nfit/dsm_mask", ctl_base);
> if (sysfs_read_attr(ctx, path, buf) < 0)
> bus->nfit_dsm_mask = 0;
> @@ -1050,6 +1098,11 @@ NDCTL_EXPORT int ndctl_bus_has_of_node(struct
> ndctl_bus *bus)
> return bus->has_of_node;
> }
>
> +NDCTL_EXPORT int ndctl_bus_has_cxl(struct ndctl_bus *bus)
> +{
> + return bus->has_cxl;
> +}
> +
> NDCTL_EXPORT int ndctl_bus_is_papr_scm(struct ndctl_bus *bus)
> {
> char buf[SYSFS_ATTR_SIZE];
> diff --git a/ndctl/lib/libndctl.sym b/ndctl/lib/libndctl.sym
> index c933163c0380..3a3e8bbd63ef 100644
> --- a/ndctl/lib/libndctl.sym
> +++ b/ndctl/lib/libndctl.sym
> @@ -465,4 +465,5 @@ LIBNDCTL_27 {
>
> LIBNDCTL_28 {
> ndctl_dimm_disable_master_passphrase;
> + ndctl_bus_has_cxl;
> } LIBNDCTL_27;
> diff --git a/ndctl/lib/private.h b/ndctl/lib/private.h
> index e5c56295556d..46bc8908bd90 100644
> --- a/ndctl/lib/private.h
> +++ b/ndctl/lib/private.h
> @@ -163,6 +163,7 @@ struct ndctl_bus {
> int regions_init;
> int has_nfit;
> int has_of_node;
> + int has_cxl;
I was going to say boolean again, but I see the pattern above.
I guess, When in Rome...
> char *bus_path;
> char *bus_buf;
> size_t buf_len;
> diff --git a/ndctl/libndctl.h b/ndctl/libndctl.h
> index c52e82a6f826..91ef0f42f654 100644
> --- a/ndctl/libndctl.h
> +++ b/ndctl/libndctl.h
> @@ -133,6 +133,7 @@ struct ndctl_bus *ndctl_bus_get_next(struct ndctl_bus
> *bus);
> struct ndctl_ctx *ndctl_bus_get_ctx(struct ndctl_bus *bus);
> int ndctl_bus_has_nfit(struct ndctl_bus *bus);
> int ndctl_bus_has_of_node(struct ndctl_bus *bus);
> +int ndctl_bus_has_cxl(struct ndctl_bus *bus);
> int ndctl_bus_is_papr_scm(struct ndctl_bus *bus);
> unsigned int ndctl_bus_get_major(struct ndctl_bus *bus);
> unsigned int ndctl_bus_get_minor(struct ndctl_bus *bus);
>
>
>
