diff options
Diffstat (limited to 'arch/s390/mm/mem_detect.c')
| -rw-r--r-- | arch/s390/mm/mem_detect.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/arch/s390/mm/mem_detect.c b/arch/s390/mm/mem_detect.c index 854c08448de..ec00576bf8d 100644 --- a/arch/s390/mm/mem_detect.c +++ b/arch/s390/mm/mem_detect.c @@ -12,7 +12,7 @@ #define ADDR2G (1ULL << 31) -static void find_memory_chunks(struct mem_chunk chunk[]) +static void find_memory_chunks(struct mem_chunk chunk[], unsigned long maxsize) { unsigned long long memsize, rnmax, rzm; unsigned long addr = 0, size; @@ -27,6 +27,8 @@ static void find_memory_chunks(struct mem_chunk chunk[]) rzm = min(ADDR2G, rzm); memsize = memsize ? min(ADDR2G, memsize) : ADDR2G; } + if (maxsize) + memsize = memsize ? min((unsigned long)memsize, maxsize) : maxsize; do { size = 0; type = tprot(addr); @@ -36,6 +38,8 @@ static void find_memory_chunks(struct mem_chunk chunk[]) break; } while (type == tprot(addr + size)); if (type == CHUNK_READ_WRITE || type == CHUNK_READ_ONLY) { + if (memsize && (addr + size > memsize)) + size = memsize - addr; chunk[i].addr = addr; chunk[i].size = size; chunk[i].type = type; @@ -45,7 +49,20 @@ static void find_memory_chunks(struct mem_chunk chunk[]) } while (addr < memsize && i < MEMORY_CHUNKS); } -void detect_memory_layout(struct mem_chunk chunk[]) +/** + * detect_memory_layout - fill mem_chunk array with memory layout data + * @chunk: mem_chunk array to be filled + * @maxsize: maximum address where memory detection should stop + * + * Fills the passed in memory chunk array with the memory layout of the + * machine. The array must have a size of at least MEMORY_CHUNKS and will + * be fully initialized afterwards. + * If the maxsize paramater has a value > 0 memory detection will stop at + * that address. It is guaranteed that all chunks have an ending address + * that is smaller than maxsize. + * If maxsize is 0 all memory will be detected. + */ +void detect_memory_layout(struct mem_chunk chunk[], unsigned long maxsize) { unsigned long flags, flags_dat, cr0; @@ -69,7 +86,7 @@ void detect_memory_layout(struct mem_chunk chunk[]) } __ctl_store(cr0, 0, 0); __ctl_clear_bit(0, 28); - find_memory_chunks(chunk); + find_memory_chunks(chunk, maxsize); __ctl_load(cr0, 0, 0); out: __arch_local_irq_ssm(flags_dat); |