diff options
author | David Gibson <david@gibson.dropbear.id.au> | 2016-02-09 13:32:42 +1000 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2016-03-01 22:04:18 +1100 |
commit | 1dace6c665ec59bdc4eeafa4db7228c1a673e2e2 (patch) | |
tree | d0c5f98ef0e47bc2fe19a8f25378e6aecd3e8cc9 /arch/powerpc/mm | |
parent | 27828f98a0522ad4a745a80407d051e5874c8d93 (diff) | |
download | linux-1dace6c665ec59bdc4eeafa4db7228c1a673e2e2.tar.gz linux-1dace6c665ec59bdc4eeafa4db7228c1a673e2e2.tar.bz2 linux-1dace6c665ec59bdc4eeafa4db7228c1a673e2e2.zip |
powerpc/mm: Clean up memory hotplug failure paths
This makes a number of cleanups to handling of mapping failures during
memory hotplug on Power:
For errors creating the linear mapping for the hot-added region:
* This is now reported with EFAULT which is more appropriate than the
previous EINVAL (the failure is unlikely to be related to the
function's parameters)
* An error in this path now prints a warning message, rather than just
silently failing to add the extra memory.
* Previously a failure here could result in the region being partially
mapped. We now clean up any partial mapping before failing.
For errors creating the vmemmap for the hot-added region:
* This is now reported with EFAULT instead of causing a BUG() - this
could happen for external reason (e.g. full hash table) so it's better
to handle this non-fatally
* An error message is also printed, so the failure won't be silent
* As above a failure could cause a partially mapped region, we now
clean this up. [mpe: move htab_remove_mapping() out of #ifdef
CONFIG_MEMORY_HOTPLUG to enable this]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm')
-rw-r--r-- | arch/powerpc/mm/hash_utils_64.c | 15 | ||||
-rw-r--r-- | arch/powerpc/mm/init_64.c | 38 | ||||
-rw-r--r-- | arch/powerpc/mm/mem.c | 10 |
3 files changed, 44 insertions, 19 deletions
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index 44f145a66578..335cd4115646 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -263,7 +263,6 @@ int htab_bolt_mapping(unsigned long vstart, unsigned long vend, return ret < 0 ? ret : 0; } -#ifdef CONFIG_MEMORY_HOTPLUG int htab_remove_mapping(unsigned long vstart, unsigned long vend, int psize, int ssize) { @@ -290,7 +289,6 @@ int htab_remove_mapping(unsigned long vstart, unsigned long vend, return ret; } -#endif /* CONFIG_MEMORY_HOTPLUG */ static int __init htab_dt_scan_seg_sizes(unsigned long node, const char *uname, int depth, @@ -640,9 +638,16 @@ static unsigned long __init htab_get_table_size(void) #ifdef CONFIG_MEMORY_HOTPLUG int create_section_mapping(unsigned long start, unsigned long end) { - return htab_bolt_mapping(start, end, __pa(start), - pgprot_val(PAGE_KERNEL), mmu_linear_psize, - mmu_kernel_ssize); + int rc = htab_bolt_mapping(start, end, __pa(start), + pgprot_val(PAGE_KERNEL), mmu_linear_psize, + mmu_kernel_ssize); + + if (rc < 0) { + int rc2 = htab_remove_mapping(start, end, mmu_linear_psize, + mmu_kernel_ssize); + BUG_ON(rc2 && (rc2 != -ENOENT)); + } + return rc; } int remove_section_mapping(unsigned long start, unsigned long end) diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c index baa1a23488d3..fbc9448cca63 100644 --- a/arch/powerpc/mm/init_64.c +++ b/arch/powerpc/mm/init_64.c @@ -188,9 +188,9 @@ static int __meminit vmemmap_populated(unsigned long start, int page_size) */ #ifdef CONFIG_PPC_BOOK3E -static void __meminit vmemmap_create_mapping(unsigned long start, - unsigned long page_size, - unsigned long phys) +static int __meminit vmemmap_create_mapping(unsigned long start, + unsigned long page_size, + unsigned long phys) { /* Create a PTE encoding without page size */ unsigned long i, flags = _PAGE_PRESENT | _PAGE_ACCESSED | @@ -208,6 +208,8 @@ static void __meminit vmemmap_create_mapping(unsigned long start, */ for (i = 0; i < page_size; i += PAGE_SIZE) BUG_ON(map_kernel_page(start + i, phys, flags)); + + return 0; } #ifdef CONFIG_MEMORY_HOTPLUG @@ -217,15 +219,20 @@ static void vmemmap_remove_mapping(unsigned long start, } #endif #else /* CONFIG_PPC_BOOK3E */ -static void __meminit vmemmap_create_mapping(unsigned long start, - unsigned long page_size, - unsigned long phys) +static int __meminit vmemmap_create_mapping(unsigned long start, + unsigned long page_size, + unsigned long phys) { - int mapped = htab_bolt_mapping(start, start + page_size, phys, - pgprot_val(PAGE_KERNEL), - mmu_vmemmap_psize, - mmu_kernel_ssize); - BUG_ON(mapped < 0); + int rc = htab_bolt_mapping(start, start + page_size, phys, + pgprot_val(PAGE_KERNEL), + mmu_vmemmap_psize, mmu_kernel_ssize); + if (rc < 0) { + int rc2 = htab_remove_mapping(start, start + page_size, + mmu_vmemmap_psize, + mmu_kernel_ssize); + BUG_ON(rc2 && (rc2 != -ENOENT)); + } + return rc; } #ifdef CONFIG_MEMORY_HOTPLUG @@ -304,6 +311,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node) for (; start < end; start += page_size) { void *p; + int rc; if (vmemmap_populated(start, page_size)) continue; @@ -317,7 +325,13 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node) pr_debug(" * %016lx..%016lx allocated at %p\n", start, start + page_size, p); - vmemmap_create_mapping(start, page_size, __pa(p)); + rc = vmemmap_create_mapping(start, page_size, __pa(p)); + if (rc < 0) { + pr_warning( + "vmemmap_populate: Unable to create vmemmap mapping: %d\n", + rc); + return -EFAULT; + } } return 0; diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index d0f0a514b04e..f980da6d7569 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -119,12 +119,18 @@ int arch_add_memory(int nid, u64 start, u64 size, bool for_device) struct zone *zone; unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; + int rc; pgdata = NODE_DATA(nid); start = (unsigned long)__va(start); - if (create_section_mapping(start, start + size)) - return -EINVAL; + rc = create_section_mapping(start, start + size); + if (rc) { + pr_warning( + "Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n", + start, start + size, rc); + return -EFAULT; + } /* this should work for most non-highmem platforms */ zone = pgdata->node_zones + |