[pxe] Create pxe_[de]activate() wrapper functions

Merge the pxe_set_netdev()+pxe_[un]hook_int1a() pattern into a single
pxe_[de]activate() call.

diff --git a/src/arch/i386/image/pxe_image.c b/src/arch/i386/image/pxe_image.c
index fde8f09..63429f8 100644 (file)
--- a/src/arch/i386/image/pxe_image.c
+++ b/src/arch/i386/image/pxe_image.c
@@ -44,27 +44,24 @@ struct image_type pxe_image_type __image_type ( PROBE_PXE );
  * @ret rc             Return status code
  */
 static int pxe_exec ( struct image *image ) {
+       struct net_device *netdev;
        int rc;
 
-       /* Ensure that PXE stack is ready to use */
-       pxe_hook_int1a();
-
        /* Arbitrarily pick the most recently opened network device */
-       pxe_set_netdev ( last_opened_netdev() );
-
-       /* Many things will break if pxe_netdev is NULL */
-       if ( ! pxe_netdev ) {
+       if ( ( netdev = last_opened_netdev() ) == NULL ) {
                DBGC ( image, "IMAGE %p could not locate PXE net device\n",
                       image );
                return -ENODEV;
        }
 
+       /* Activate PXE */
+       pxe_activate ( netdev );
+
        /* Start PXE NBP */
        rc = pxe_start_nbp();
 
        /* Deactivate PXE */
-       pxe_set_netdev ( NULL );
-       pxe_unhook_int1a();
+       pxe_deactivate();
 
        return rc;
 }

diff --git a/src/arch/i386/include/pxe_call.h b/src/arch/i386/include/pxe_call.h
index 05d7051..50667e6 100644 (file)
--- a/src/arch/i386/include/pxe_call.h
+++ b/src/arch/i386/include/pxe_call.h
@@ -11,6 +11,8 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #include <pxe_api.h>
 #include <realmode.h>
 
+struct net_device;
+
 /** PXE load address segment */
 #define PXE_LOAD_SEGMENT 0
 
@@ -28,8 +30,8 @@ extern struct s_PXE __text16 ( ppxe );
 extern struct s_PXENV __text16 ( pxenv );
 #define pxenv __use_text16 ( pxenv )
 
-extern void pxe_hook_int1a ( void );
-extern int pxe_unhook_int1a ( void );
+extern void pxe_activate ( struct net_device *netdev );
+extern int pxe_deactivate ( void );
 extern int pxe_start_nbp ( void );
 extern __asmcall void pxe_api_call ( struct i386_all_regs *ix86 );
 

diff --git a/src/arch/i386/interface/pxe/pxe_call.c b/src/arch/i386/interface/pxe/pxe_call.c
index e15a8c1..705afca 100644 (file)
--- a/src/arch/i386/interface/pxe/pxe_call.c
+++ b/src/arch/i386/interface/pxe/pxe_call.c
@@ -37,6 +37,9 @@ extern struct segoff __text16 ( pxe_int_1a_vector );
 /** INT 1A handler */
 extern void pxe_int_1a ( void );
 
+/** INT 1A hooked flag */
+static int int_1a_hooked = 0;
+
 /** A function pointer to hold any PXE API call
  *
  * Used by pxe_api_call() to avoid large swathes of duplicated code.
@@ -364,25 +367,6 @@ __asmcall void pxe_loader_call ( struct i386_all_regs *ix86 ) {
        ix86->regs.ax = ret;
 }
 
-/**
- * Hook INT 1A for PXE
- *
- */
-void pxe_hook_int1a ( void ) {
-       hook_bios_interrupt ( 0x1a, ( unsigned int ) pxe_int_1a,
-                             &pxe_int_1a_vector );
-}
-
-/**
- * Unhook INT 1A for PXE
- *
- * @ret rc             Return status code
- */
-int pxe_unhook_int1a ( void ) {
-       return unhook_bios_interrupt ( 0x1a, ( unsigned int ) pxe_int_1a,
-                                      &pxe_int_1a_vector );
-}
-
 /**
  * Calculate byte checksum as used by PXE
  *
@@ -435,6 +419,50 @@ struct init_fn pxe_init_fn __init_fn ( INIT_NORMAL ) = {
        .initialise = pxe_init_structures,
 };
 
+/**
+ * Activate PXE stack
+ *
+ * @v netdev           Net device to use as PXE net device
+ */
+void pxe_activate ( struct net_device *netdev ) {
+
+       /* Ensure INT 1A is hooked */
+       if ( ! int_1a_hooked ) {
+               hook_bios_interrupt ( 0x1a, ( unsigned int ) pxe_int_1a,
+                                     &pxe_int_1a_vector );
+               int_1a_hooked = 1;
+       }
+
+       /* Set PXE network device */
+       pxe_set_netdev ( netdev );
+}
+
+/**
+ * Deactivate PXE stack
+ *
+ * @ret rc             Return status code
+ */
+int pxe_deactivate ( void ) {
+       int rc;
+
+       /* Clear PXE network device */
+       pxe_set_netdev ( NULL );
+
+       /* Ensure INT 1A is unhooked, if possible */
+       if ( int_1a_hooked ) {
+               if ( ( rc = unhook_bios_interrupt ( 0x1a,
+                                                   (unsigned int) pxe_int_1a,
+                                                   &pxe_int_1a_vector ))!= 0){
+                       DBG ( "Could not unhook INT 1A: %s\n",
+                             strerror ( rc ) );
+                       return rc;
+               }
+               int_1a_hooked = 0;
+       }
+
+       return 0;
+}
+
 /**
  * Start PXE NBP at 0000:7c00
  *

diff --git a/src/arch/i386/interface/pxe/pxe_preboot.c b/src/arch/i386/interface/pxe/pxe_preboot.c
index 5ea06e9..21461a5 100644 (file)
--- a/src/arch/i386/interface/pxe/pxe_preboot.c
+++ b/src/arch/i386/interface/pxe/pxe_preboot.c
@@ -296,11 +296,8 @@ PXENV_EXIT_t pxenv_start_undi ( struct s_PXENV_START_UNDI *start_undi ) {
        }
        DBG ( " using netdev %s", netdev->name );
 
-       /* Save as PXE net device */
-       pxe_set_netdev ( netdev );
-
-       /* Hook INT 1A */
-       pxe_hook_int1a();
+       /* Activate PXE */
+       pxe_activate ( netdev );
 
        start_undi->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
@@ -313,11 +310,8 @@ PXENV_EXIT_t pxenv_start_undi ( struct s_PXENV_START_UNDI *start_undi ) {
 PXENV_EXIT_t pxenv_stop_undi ( struct s_PXENV_STOP_UNDI *stop_undi ) {
        DBG ( "PXENV_STOP_UNDI" );
 
-       /* Unhook INT 1A */
-       pxe_unhook_int1a();
-
-       /* Clear PXE net device */
-       pxe_set_netdev ( NULL );
+       /* Deactivate PXE */
+       pxe_deactivate();
 
        /* Prepare for unload */
        shutdown ( SHUTDOWN_BOOT );