diff options
Diffstat (limited to 'arch/x86/xen/p2m.c')
| -rw-r--r-- | arch/x86/xen/p2m.c | 123 |
1 files changed, 106 insertions, 17 deletions
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 9bdc3b656b2c..56914e21e303 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -70,6 +70,7 @@ #include <linux/memblock.h> #include <linux/slab.h> #include <linux/vmalloc.h> +#include <linux/acpi.h> #include <asm/cache.h> #include <asm/setup.h> @@ -80,8 +81,8 @@ #include <asm/xen/hypervisor.h> #include <xen/balloon.h> #include <xen/grant_table.h> +#include <xen/hvc-console.h> -#include "multicalls.h" #include "xen-ops.h" #define P2M_MID_PER_PAGE (PAGE_SIZE / sizeof(unsigned long *)) @@ -177,13 +178,7 @@ static void p2m_init_identity(unsigned long *p2m, unsigned long pfn) static void * __ref alloc_p2m_page(void) { if (unlikely(!slab_is_available())) { - void *ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE); - - if (!ptr) - panic("%s: Failed to allocate %lu bytes align=0x%lx\n", - __func__, PAGE_SIZE, PAGE_SIZE); - - return ptr; + return memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE); } return (void *)__get_free_page(GFP_KERNEL); @@ -555,7 +550,6 @@ int xen_alloc_p2m_entry(unsigned long pfn) /* Separately check the mid mfn level */ unsigned long missing_mfn; unsigned long mid_mfn_mfn; - unsigned long old_mfn; mid_mfn = alloc_p2m_page(); if (!mid_mfn) @@ -565,12 +559,12 @@ int xen_alloc_p2m_entry(unsigned long pfn) missing_mfn = virt_to_mfn(p2m_mid_missing_mfn); mid_mfn_mfn = virt_to_mfn(mid_mfn); - old_mfn = cmpxchg(top_mfn_p, missing_mfn, mid_mfn_mfn); - if (old_mfn != missing_mfn) { - free_p2m_page(mid_mfn); - mid_mfn = mfn_to_virt(old_mfn); - } else { + /* try_cmpxchg() updates missing_mfn on failure. */ + if (try_cmpxchg(top_mfn_p, &missing_mfn, mid_mfn_mfn)) { p2m_top_mfn_p[topidx] = mid_mfn; + } else { + free_p2m_page(mid_mfn); + mid_mfn = mfn_to_virt(missing_mfn); } } } else { @@ -731,7 +725,7 @@ int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, * immediate unmapping. */ map_ops[i].status = GNTST_general_error; - unmap[0].host_addr = map_ops[i].host_addr, + unmap[0].host_addr = map_ops[i].host_addr; unmap[0].handle = map_ops[i].handle; map_ops[i].handle = INVALID_GRANT_HANDLE; if (map_ops[i].flags & GNTMAP_device_map) @@ -741,7 +735,7 @@ int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, if (kmap_ops) { kmap_ops[i].status = GNTST_general_error; - unmap[1].host_addr = kmap_ops[i].host_addr, + unmap[1].host_addr = kmap_ops[i].host_addr; unmap[1].handle = kmap_ops[i].handle; kmap_ops[i].handle = INVALID_GRANT_HANDLE; if (kmap_ops[i].flags & GNTMAP_device_map) @@ -794,9 +788,104 @@ int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, return ret; } +/* Remapped non-RAM areas */ +#define NR_NONRAM_REMAP 4 +static struct nonram_remap { + phys_addr_t maddr; + phys_addr_t paddr; + size_t size; +} xen_nonram_remap[NR_NONRAM_REMAP] __ro_after_init; +static unsigned int nr_nonram_remap __ro_after_init; + +/* + * Do the real remapping of non-RAM regions as specified in the + * xen_nonram_remap[] array. + * In case of an error just crash the system. + */ +void __init xen_do_remap_nonram(void) +{ + unsigned int i; + unsigned int remapped = 0; + const struct nonram_remap *remap = xen_nonram_remap; + unsigned long pfn, mfn, end_pfn; + + for (i = 0; i < nr_nonram_remap; i++) { + end_pfn = PFN_UP(remap->paddr + remap->size); + pfn = PFN_DOWN(remap->paddr); + mfn = PFN_DOWN(remap->maddr); + while (pfn < end_pfn) { + if (!set_phys_to_machine(pfn, mfn)) + panic("Failed to set p2m mapping for pfn=%lx mfn=%lx\n", + pfn, mfn); + + pfn++; + mfn++; + remapped++; + } + + remap++; + } + + pr_info("Remapped %u non-RAM page(s)\n", remapped); +} + +#ifdef CONFIG_ACPI +/* + * Xen variant of acpi_os_ioremap() taking potentially remapped non-RAM + * regions into account. + * Any attempt to map an area crossing a remap boundary will produce a + * WARN() splat. + * phys is related to remap->maddr on input and will be rebased to remap->paddr. + */ +static void __iomem *xen_acpi_os_ioremap(acpi_physical_address phys, + acpi_size size) +{ + unsigned int i; + const struct nonram_remap *remap = xen_nonram_remap; + + for (i = 0; i < nr_nonram_remap; i++) { + if (phys + size > remap->maddr && + phys < remap->maddr + remap->size) { + WARN_ON(phys < remap->maddr || + phys + size > remap->maddr + remap->size); + phys += remap->paddr - remap->maddr; + break; + } + } + + return x86_acpi_os_ioremap(phys, size); +} +#endif /* CONFIG_ACPI */ + +/* + * Add a new non-RAM remap entry. + * In case of no free entry found, just crash the system. + */ +void __init xen_add_remap_nonram(phys_addr_t maddr, phys_addr_t paddr, + unsigned long size) +{ + BUG_ON((maddr & ~PAGE_MASK) != (paddr & ~PAGE_MASK)); + + if (nr_nonram_remap == NR_NONRAM_REMAP) { + xen_raw_console_write("Number of required E820 entry remapping actions exceed maximum value\n"); + BUG(); + } + +#ifdef CONFIG_ACPI + /* Switch to the Xen acpi_os_ioremap() variant. */ + if (nr_nonram_remap == 0) + acpi_os_ioremap = xen_acpi_os_ioremap; +#endif + + xen_nonram_remap[nr_nonram_remap].maddr = maddr; + xen_nonram_remap[nr_nonram_remap].paddr = paddr; + xen_nonram_remap[nr_nonram_remap].size = size; + + nr_nonram_remap++; +} + #ifdef CONFIG_XEN_DEBUG_FS #include <linux/debugfs.h> -#include "debugfs.h" static int p2m_dump_show(struct seq_file *m, void *v) { static const char * const type_name[] = { |