[PATCH v2 1/5] pc-bios/s390-ccw: Allow to select a different pxelinux.cfg entry via loadparm

Thomas Huth posted 5 patches 4 months, 1 week ago
Maintainers: Thomas Huth <thuth@redhat.com>, Christian Borntraeger <borntraeger@linux.ibm.com>, Jared Rossi <jrossi@linux.ibm.com>, Zhuoying Cai <zycai@linux.ibm.com>, Halil Pasic <pasic@linux.ibm.com>, Eric Farman <farman@linux.ibm.com>, Matthew Rosato <mjrosato@linux.ibm.com>
[PATCH v2 1/5] pc-bios/s390-ccw: Allow to select a different pxelinux.cfg entry via loadparm
Posted by Thomas Huth 4 months, 1 week ago
From: Thomas Huth <thuth@redhat.com>

Since we're linking the network booting code into the main firmware
binary nowadays, we can support the "loadparm" parameter now quite
easily for pxelinux.cfg config files that contain multiple entries.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 pc-bios/s390-ccw/netmain.c | 32 ++++++++++++++++++++++++--------
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
index 719a547ada0..c0aafca22d2 100644
--- a/pc-bios/s390-ccw/netmain.c
+++ b/pc-bios/s390-ccw/netmain.c
@@ -332,6 +332,27 @@ static int load_kernel_with_initrd(filename_ip_t *fn_ip,
     return rc;
 }
 
+static int net_select_and_load_kernel(filename_ip_t *fn_ip,
+                                      int num_ent, int selected,
+                                      struct pl_cfg_entry *entries)
+{
+    unsigned int loadparm = get_loadparm_index();
+
+    if (num_ent <= 0) {
+        return -1;
+    }
+
+    IPL_assert(loadparm <= num_ent,
+               "loadparm is set to an entry that is not available in the "
+               "pxelinux.cfg file!");
+
+    if (loadparm > 0) {
+        selected = loadparm - 1;
+    }
+
+    return load_kernel_with_initrd(fn_ip, &entries[selected]);
+}
+
 #define MAX_PXELINUX_ENTRIES 16
 
 static int net_try_pxelinux_cfg(filename_ip_t *fn_ip)
@@ -343,11 +364,8 @@ static int net_try_pxelinux_cfg(filename_ip_t *fn_ip)
                                       DEFAULT_TFTP_RETRIES,
                                       cfgbuf, sizeof(cfgbuf),
                                       entries, MAX_PXELINUX_ENTRIES, &def_ent);
-    if (num_ent > 0) {
-        return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
-    }
 
-    return -1;
+    return net_select_and_load_kernel(fn_ip, num_ent, def_ent, entries);
 }
 
 /**
@@ -433,10 +451,8 @@ static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
 
             num_ent = pxelinux_parse_cfg(cfgbuf, sizeof(cfgbuf), entries,
                                          MAX_PXELINUX_ENTRIES, &def_ent);
-            if (num_ent <= 0) {
-                return -1;
-            }
-            return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
+            return net_select_and_load_kernel(fn_ip, num_ent, def_ent,
+                                              entries);
         }
     }
 
-- 
2.50.0
Re: [PATCH v2 1/5] pc-bios/s390-ccw: Allow to select a different pxelinux.cfg entry via loadparm
Posted by Jared Rossi 4 months, 1 week ago
Reviewed-by: Jared Rossi <jrossi@linux.ibm.com>

On 7/9/25 4:34 AM, Thomas Huth wrote:
> From: Thomas Huth <thuth@redhat.com>
>
> Since we're linking the network booting code into the main firmware
> binary nowadays, we can support the "loadparm" parameter now quite
> easily for pxelinux.cfg config files that contain multiple entries.
>
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>   pc-bios/s390-ccw/netmain.c | 32 ++++++++++++++++++++++++--------
>   1 file changed, 24 insertions(+), 8 deletions(-)
>
> diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
> index 719a547ada0..c0aafca22d2 100644
> --- a/pc-bios/s390-ccw/netmain.c
> +++ b/pc-bios/s390-ccw/netmain.c
> @@ -332,6 +332,27 @@ static int load_kernel_with_initrd(filename_ip_t *fn_ip,
>       return rc;
>   }
>   
> +static int net_select_and_load_kernel(filename_ip_t *fn_ip,
> +                                      int num_ent, int selected,
> +                                      struct pl_cfg_entry *entries)
> +{
> +    unsigned int loadparm = get_loadparm_index();
> +
> +    if (num_ent <= 0) {
> +        return -1;
> +    }
> +
> +    IPL_assert(loadparm <= num_ent,
> +               "loadparm is set to an entry that is not available in the "
> +               "pxelinux.cfg file!");
> +
> +    if (loadparm > 0) {
> +        selected = loadparm - 1;
> +    }
> +
> +    return load_kernel_with_initrd(fn_ip, &entries[selected]);
> +}
> +
>   #define MAX_PXELINUX_ENTRIES 16
>   
>   static int net_try_pxelinux_cfg(filename_ip_t *fn_ip)
> @@ -343,11 +364,8 @@ static int net_try_pxelinux_cfg(filename_ip_t *fn_ip)
>                                         DEFAULT_TFTP_RETRIES,
>                                         cfgbuf, sizeof(cfgbuf),
>                                         entries, MAX_PXELINUX_ENTRIES, &def_ent);
> -    if (num_ent > 0) {
> -        return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
> -    }
>   
> -    return -1;
> +    return net_select_and_load_kernel(fn_ip, num_ent, def_ent, entries);
>   }
>   
>   /**
> @@ -433,10 +451,8 @@ static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
>   
>               num_ent = pxelinux_parse_cfg(cfgbuf, sizeof(cfgbuf), entries,
>                                            MAX_PXELINUX_ENTRIES, &def_ent);
> -            if (num_ent <= 0) {
> -                return -1;
> -            }
> -            return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
> +            return net_select_and_load_kernel(fn_ip, num_ent, def_ent,
> +                                              entries);
>           }
>       }
>