diff options
Diffstat (limited to 'qemu/roms/ipxe/src/arch/i386/interface/pcbios/biosint.c')
-rw-r--r-- | qemu/roms/ipxe/src/arch/i386/interface/pcbios/biosint.c | 92 |
1 files changed, 0 insertions, 92 deletions
diff --git a/qemu/roms/ipxe/src/arch/i386/interface/pcbios/biosint.c b/qemu/roms/ipxe/src/arch/i386/interface/pcbios/biosint.c deleted file mode 100644 index 3b8e80438..000000000 --- a/qemu/roms/ipxe/src/arch/i386/interface/pcbios/biosint.c +++ /dev/null @@ -1,92 +0,0 @@ -#include <errno.h> -#include <realmode.h> -#include <biosint.h> - -/** - * @file BIOS interrupts - * - */ - -FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); - -/** - * Hook INT vector - * - * @v interrupt INT number - * @v handler Offset within .text16 to interrupt handler - * @v chain_vector Vector for chaining to previous handler - * - * Hooks in an i386 INT handler. The handler itself must reside - * within the .text16 segment. @c chain_vector will be filled in with - * the address of the previously-installed handler for this interrupt; - * the handler should probably exit by ljmping via this vector. - */ -void hook_bios_interrupt ( unsigned int interrupt, unsigned int handler, - struct segoff *chain_vector ) { - struct segoff vector = { - .segment = rm_cs, - .offset = handler, - }; - - DBG ( "Hooking INT %#02x to %04x:%04x\n", - interrupt, rm_cs, handler ); - - if ( ( chain_vector->segment != 0 ) || - ( chain_vector->offset != 0 ) ) { - /* Already hooked; do nothing */ - DBG ( "...already hooked\n" ); - return; - } - - copy_from_real ( chain_vector, 0, ( interrupt * 4 ), - sizeof ( *chain_vector ) ); - DBG ( "...chaining to %04x:%04x\n", - chain_vector->segment, chain_vector->offset ); - if ( DBG_LOG ) { - char code[64]; - copy_from_real ( code, chain_vector->segment, - chain_vector->offset, sizeof ( code ) ); - DBG_HDA ( *chain_vector, code, sizeof ( code ) ); - } - - copy_to_real ( 0, ( interrupt * 4 ), &vector, sizeof ( vector ) ); - hooked_bios_interrupts++; -} - -/** - * Unhook INT vector - * - * @v interrupt INT number - * @v handler Offset within .text16 to interrupt handler - * @v chain_vector Vector containing address of previous handler - * - * Unhooks an i386 interrupt handler hooked by hook_i386_vector(). - * Note that this operation may fail, if some external code has hooked - * the vector since we hooked in our handler. If it fails, it means - * that it is not possible to unhook our handler, and we must leave it - * (and its chaining vector) resident in memory. - */ -int unhook_bios_interrupt ( unsigned int interrupt, unsigned int handler, - struct segoff *chain_vector ) { - struct segoff vector; - - DBG ( "Unhooking INT %#02x from %04x:%04x\n", - interrupt, rm_cs, handler ); - - copy_from_real ( &vector, 0, ( interrupt * 4 ), sizeof ( vector ) ); - if ( ( vector.segment != rm_cs ) || ( vector.offset != handler ) ) { - DBG ( "...cannot unhook; vector points to %04x:%04x\n", - vector.segment, vector.offset ); - return -EBUSY; - } - - DBG ( "...restoring to %04x:%04x\n", - chain_vector->segment, chain_vector->offset ); - copy_to_real ( 0, ( interrupt * 4 ), chain_vector, - sizeof ( *chain_vector ) ); - - chain_vector->segment = 0; - chain_vector->offset = 0; - hooked_bios_interrupts--; - return 0; -} |