BMC/Intel-BMC/linux.git/arch/powerpc/mm/init_64.c, branch dev

powerpc/mm: Free string after creating kmem cache

2015-03-26T04:23:17+00:00

kmem_cache_create()->kmem_cache_create_memcg()->kstrdup() allocates new space and copys name's content, so it is safe to free name memory after calling kmem_cache_create(). Else kmemleak will report the below warning: unreferenced object 0xc0000000f9002160 (size 16): comm "swapper/0", pid 0, jiffies 4294892296 (age 1386.640s) hex dump (first 16 bytes): 70 67 74 61 62 6c 65 2d 32 5e 39 00 de ad be ef pgtable-2^9..... backtrace: [] .kvasprintf+0x5c/0xa0 [] .kasprintf+0x2c/0x50 [] .pgtable_cache_add+0xac/0x100 [] .pgtable_cache_init+0x24/0x80 [] .start_kernel+0x228/0x4c8 [] .start_here_common+0x24/0x90 Signed-off-by: Yanjiang Jin Signed-off-by: Michael Ellerman

powerpc: Remove superfluous bootmem includes

2014-11-09T22:59:26+00:00

Lots of places included bootmem.h even when not using bootmem. Signed-off-by: Anton Blanchard Tested-by: Emil Medve Signed-off-by: Michael Ellerman

powerpc: Move htab_remove_mapping function prototype into header file

2014-09-25T13:14:44+00:00

A recent patch added a function prototype for htab_remove_mapping in c code. Fix it. Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman

powerpc: start loop at section start of start in vmemmap_populated()

2014-08-05T06:34:23+00:00

vmemmap_populated() checks whether the [start, start + page_size) has valid pfn numbers, to know whether a vmemmap mapping has been created that includes this range. Some range before end might not be checked by this loop: sec11start......start11..sec11end/sec12start..end....start12..sec12end as the above, for start11(section 11), it checks [sec11start, sec11end), and loop ends as the next start(start12) is bigger than end. However, [sec11end/sec12start, end) is not checked here. So before the loop, adjust the start to be the start of the section, so we don't miss ranges like the above. After we adjust start to be the start of the section, it also means it's aligned with vmemmap as of the sizeof struct page, so we could use page_to_pfn directly in the loop. Signed-off-by: Li Zhong Cc: Nathan Fontenot Acked-by: Nathan Fontenot Signed-off-by: Benjamin Herrenschmidt

powerpc: implement vmemmap_free()

2014-08-05T06:34:19+00:00

vmemmap_free() does the opposite of vmemap_populate(). This patch also puts vmemmap_free() and vmemmap_list_free() into CONFIG_MEMMORY_HOTPLUG. Signed-off-by: Li Zhong Cc: Nathan Fontenot Acked-by: Nathan Fontenot Signed-off-by: Benjamin Herrenschmidt

powerpc: implement vmemmap_remove_mapping() for BOOK3S

2014-08-05T06:34:15+00:00

This is to be called in vmemmap_free(), leave the implementation on BOOK3E empty as before. Signed-off-by: Li Zhong Cc: Nathan Fontenot Acked-by: Nathan Fontenot Signed-off-by: Benjamin Herrenschmidt

powerpc: implement vmemmap_list_free()

2014-08-05T06:34:10+00:00

This patch implements vmemmap_list_free() for vmemmap_free(). The freed entries will be removed from vmemmap_list, and form a freed list, with next as the header. The next position in the last allocated page is kept at the list tail. When allocation, if there are freed entries left, get it from the freed list; if no freed entries left, get it like before from the last allocated pages. With this change, realmode_pfn_to_page() also needs to be changed to walk all the entries in the vmemmap_list, as the virt_addr of the entries might not be stored in order anymore. It helps to reuse the memory when continuous doing memory hot-plug/remove operations, but didn't reclaim the pages already allocated, so the memory usage will only increase, but won't exceed the value for the largest memory configuration. Signed-off-by: Li Zhong Cc: Nathan Fontenot Acked-by: Nathan Fontenot Signed-off-by: Benjamin Herrenschmidt

powerpc: Prepare to support kernel handling of IOMMU map/unmap

2013-10-11T06:24:39+00:00

The current VFIO-on-POWER implementation supports only user mode driven mapping, i.e. QEMU is sending requests to map/unmap pages. However this approach is really slow, so we want to move that to KVM. Since H_PUT_TCE can be extremely performance sensitive (especially with network adapters where each packet needs to be mapped/unmapped) we chose to implement that as a "fast" hypercall directly in "real mode" (processor still in the guest context but MMU off). To be able to do that, we need to provide some facilities to access the struct page count within that real mode environment as things like the sparsemem vmemmap mappings aren't accessible. This adds an API function realmode_pfn_to_page() to get page struct when MMU is off. This adds to MM a new function put_page_unless_one() which drops a page if counter is bigger than 1. It is going to be used when MMU is off (for example, real mode on PPC64) and we want to make sure that page release will not happen in real mode as it may crash the kernel in a horrible way. CONFIG_SPARSEMEM_VMEMMAP and CONFIG_FLATMEM are supported. Cc: linux-mm@kvack.org Cc: Benjamin Herrenschmidt Cc: Andrew Morton Reviewed-by: Paul Mackerras Signed-off-by: Paul Mackerras Signed-off-by: Alexey Kardashevskiy Signed-off-by: Benjamin Herrenschmidt

powerpc: Fix memory hotplug with sparse vmemmap

2013-10-03T07:21:38+00:00

Previous commit 46723bfa540... introduced a new config option HAVE_BOOTMEM_INFO_NODE that ended up breaking memory hot-remove for ppc when sparse vmemmap is not defined. This patch defines HAVE_BOOTMEM_INFO_NODE for ppc and adds the call to register_page_bootmem_info_node. Without this we get a BUG_ON for memory hot remove in put_page_bootmem(). This also adds a stub for register_page_bootmem_memmap to allow ppc to build with sparse vmemmap defined. Leaving this as a stub is fine since the same vmemmap addresses are also handled in vmemmap_populate and as such are properly mapped. Signed-off-by: Nathan Fontenot Signed-off-by: Benjamin Herrenschmidt CC: [v3.9+]

powerpc/THP: Double the PMD table size for THP

2013-06-21T06:01:53+00:00

THP code does PTE page allocation along with large page request and deposit them for later use. This is to ensure that we won't have any failures when we split hugepages to regular pages. On powerpc we want to use the deposited PTE page for storing hash pte slot and secondary bit information for the HPTEs. We use the second half of the pmd table to save the deposted PTE page. Reviewed-by: David Gibson Signed-off-by: Aneesh Kumar K.V Signed-off-by: Benjamin Herrenschmidt