diff options
| -rw-r--r-- | pc-bios/s390-ccw/bootmap.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c index c07553b..5ee3fcb 100644 --- a/pc-bios/s390-ccw/bootmap.c +++ b/pc-bios/s390-ccw/bootmap.c @@ -118,10 +118,26 @@ static int zipl_magic(uint8_t *ptr) return 1; } +#define FREE_SPACE_FILLER '\xAA' + +static inline bool unused_space(const void *p, unsigned int size) +{ + int i; + const unsigned char *m = p; + + for (i = 0; i < size; i++) { + if (m[i] != FREE_SPACE_FILLER) { + return false; + } + } + return true; +} + static int zipl_load_segment(struct component_entry *entry) { const int max_entries = (SECTOR_SIZE / sizeof(struct scsi_blockptr)); struct scsi_blockptr *bprs = (void*)sec; + const int bprs_size = sizeof(sec); uint64_t blockno; long address; int i; @@ -133,6 +149,7 @@ static int zipl_load_segment(struct component_entry *entry) debug_print_int("addr", address); do { + memset(bprs, FREE_SPACE_FILLER, bprs_size); if (virtio_read(blockno, (uint8_t *)bprs)) { debug_print_int("failed reading bprs at", blockno); goto fail; @@ -150,6 +167,16 @@ static int zipl_load_segment(struct component_entry *entry) if (i == (max_entries - 1)) break; + if (bprs[i].blockct == 0 && unused_space(&bprs[i + 1], + sizeof(struct scsi_blockptr))) { + /* This is a "continue" pointer. + * This ptr is the last one in the current script section. + * I.e. the next ptr must point to the unused memory area. + * The blockno is not zero, so the upper loop must continue + * reading next section of BPRS. + */ + break; + } address = virtio_load_direct(cur_desc[0], cur_desc[1], 0, (void*)address); if (address == -1) |