forked from luck/tmp_suning_uos_patched
b2a68c2356
Currently dev/mem for s390 provides only real memory access. This means that the CPU prefix pages are swapped. The prefix swap for real memory works as follows: Each CPU owns a prefix register that points to a page aligned memory location "P". If this CPU accesses the address range [0,0x1fff], it is translated by the hardware to [P,P+0x1fff]. Accordingly if this CPU accesses the address range [P,P+0x1fff], it is translated by the hardware to [0,0x1fff]. Therefore, if [P,P+0x1fff] or [0,0x1fff] is read from the current /dev/mem device, the incorrectly swapped memory content is returned. With this patch the /dev/mem architecture code is modified to provide absolute memory access. This is done via the arch specific functions xlate_dev_mem_ptr() and unxlate_dev_mem_ptr(). For swapped pages on s390 the function xlate_dev_mem_ptr() now returns a new buffer with a copy of the requested absolute memory. In case the buffer was allocated, the unxlate_dev_mem_ptr() function frees it after /dev/mem code has called copy_to_user(). Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> |
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| .. | ||
| cmm.c | ||
| extmem.c | ||
| fault.c | ||
| gup.c | ||
| hugetlbpage.c | ||
| init.c | ||
| maccess.c | ||
| Makefile | ||
| mmap.c | ||
| page-states.c | ||
| pageattr.c | ||
| pgtable.c | ||
| vmem.c | ||