| Message ID | 1408610714-16204-2-git-send-email-m.szyprowski@samsung.com |
|---|---|
| State | Accepted |
| Commit | f7426b983a6a353cf21e5733e84458219c4a817e |
| Headers | show |
On Thu, Aug 21 2014, Marek Szyprowski <m.szyprowski@samsung.com> wrote: > Automatically allocated regions should not cross low/high memory boundary, > because such regions cannot be later correctly initialized due to spanning > across two memory zones. This patch adds a check for this case and a simple > code for moving region to low memory if automatically selected address might > not fit completely into high memory. > > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> > --- > mm/cma.c | 21 +++++++++++++++++++++ > 1 file changed, 21 insertions(+) > > diff --git a/mm/cma.c b/mm/cma.c > index c17751c0dcaf..4acc6aa4a086 100644 > --- a/mm/cma.c > +++ b/mm/cma.c > @@ -32,6 +32,7 @@ > #include <linux/slab.h> > #include <linux/log2.h> > #include <linux/cma.h> > +#include <linux/highmem.h> > > struct cma { > unsigned long base_pfn; > @@ -163,6 +164,8 @@ int __init cma_declare_contiguous(phys_addr_t base, > bool fixed, struct cma **res_cma) > { > struct cma *cma; > + phys_addr_t memblock_end = memblock_end_of_DRAM(); > + phys_addr_t highmem_start = __pa(high_memory); > int ret = 0; > > pr_debug("%s(size %lx, base %08lx, limit %08lx alignment %08lx)\n", > @@ -196,6 +199,24 @@ int __init cma_declare_contiguous(phys_addr_t base, > if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit)) > return -EINVAL; > > + /* > + * adjust limit to avoid crossing low/high memory boundary for > + * automatically allocated regions > + */ > + if (((limit == 0 || limit > memblock_end) && > + (memblock_end - size < highmem_start && > + memblock_end > highmem_start)) || > + (!fixed && limit > highmem_start && limit - size < highmem_start)) { > + limit = highmem_start; > + } > + > + if (fixed && base < highmem_start && base+size > highmem_start) { > + ret = -EINVAL; > + pr_err("Region at %08lx defined on low/high memory boundary (%08lx)\n", > + (unsigned long)base, (unsigned long)highmem_start); > + goto err; > + } > + > /* Reserve memory */ > if (base && fixed) { > if (memblock_is_region_reserved(base, size) || > -- > 1.9.2 >
diff --git a/mm/cma.c b/mm/cma.c index c17751c0dcaf..4acc6aa4a086 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -32,6 +32,7 @@ #include <linux/slab.h> #include <linux/log2.h> #include <linux/cma.h> +#include <linux/highmem.h> struct cma { unsigned long base_pfn; @@ -163,6 +164,8 @@ int __init cma_declare_contiguous(phys_addr_t base, bool fixed, struct cma **res_cma) { struct cma *cma; + phys_addr_t memblock_end = memblock_end_of_DRAM(); + phys_addr_t highmem_start = __pa(high_memory); int ret = 0; pr_debug("%s(size %lx, base %08lx, limit %08lx alignment %08lx)\n", @@ -196,6 +199,24 @@ int __init cma_declare_contiguous(phys_addr_t base, if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit)) return -EINVAL; + /* + * adjust limit to avoid crossing low/high memory boundary for + * automatically allocated regions + */ + if (((limit == 0 || limit > memblock_end) && + (memblock_end - size < highmem_start && + memblock_end > highmem_start)) || + (!fixed && limit > highmem_start && limit - size < highmem_start)) { + limit = highmem_start; + } + + if (fixed && base < highmem_start && base+size > highmem_start) { + ret = -EINVAL; + pr_err("Region at %08lx defined on low/high memory boundary (%08lx)\n", + (unsigned long)base, (unsigned long)highmem_start); + goto err; + } + /* Reserve memory */ if (base && fixed) { if (memblock_is_region_reserved(base, size) ||
Automatically allocated regions should not cross low/high memory boundary, because such regions cannot be later correctly initialized due to spanning across two memory zones. This patch adds a check for this case and a simple code for moving region to low memory if automatically selected address might not fit completely into high memory. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- mm/cma.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+)