From 10fe570fc16721d78afdba9689720094527c1ba3 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Tue, 9 Aug 2011 13:02:50 -0400 Subject: Revert "xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set." We don' use it anymore and there are more false positives. This reverts commit fc25151d9ac7d809239fe68de0a1490b504bb94a. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/Kconfig | 8 -------- arch/x86/xen/mmu.c | 38 -------------------------------------- 2 files changed, 46 deletions(-) (limited to 'arch/x86/xen') diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig index 5cc821cb2e0..ae559fe91c2 100644 --- a/arch/x86/xen/Kconfig +++ b/arch/x86/xen/Kconfig @@ -49,11 +49,3 @@ config XEN_DEBUG_FS help Enable statistics output and various tuning options in debugfs. Enabling this option may incur a significant performance overhead. - -config XEN_DEBUG - bool "Enable Xen debug checks" - depends on XEN - default n - help - Enable various WARN_ON checks in the Xen MMU code. - Enabling this option WILL incur a significant performance overhead. diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index f987bde77c4..3c9aecd09ed 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -495,41 +495,6 @@ static pte_t xen_make_pte(pteval_t pte) } PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte); -#ifdef CONFIG_XEN_DEBUG -pte_t xen_make_pte_debug(pteval_t pte) -{ - phys_addr_t addr = (pte & PTE_PFN_MASK); - phys_addr_t other_addr; - bool io_page = false; - pte_t _pte; - - if (pte & _PAGE_IOMAP) - io_page = true; - - _pte = xen_make_pte(pte); - - if (!addr) - return _pte; - - if (io_page && - (xen_initial_domain() || addr >= ISA_END_ADDRESS)) { - other_addr = pfn_to_mfn(addr >> PAGE_SHIFT) << PAGE_SHIFT; - WARN_ONCE(addr != other_addr, - "0x%lx is using VM_IO, but it is 0x%lx!\n", - (unsigned long)addr, (unsigned long)other_addr); - } else { - pteval_t iomap_set = (_pte.pte & PTE_FLAGS_MASK) & _PAGE_IOMAP; - other_addr = (_pte.pte & PTE_PFN_MASK); - WARN_ONCE((addr == other_addr) && (!io_page) && (!iomap_set), - "0x%lx is missing VM_IO (and wasn't fixed)!\n", - (unsigned long)addr); - } - - return _pte; -} -PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte_debug); -#endif - static pgd_t xen_make_pgd(pgdval_t pgd) { pgd = pte_pfn_to_mfn(pgd); @@ -1988,9 +1953,6 @@ void __init xen_ident_map_ISA(void) static void __init xen_post_allocator_init(void) { -#ifdef CONFIG_XEN_DEBUG - pv_mmu_ops.make_pte = PV_CALLEE_SAVE(xen_make_pte_debug); -#endif pv_mmu_ops.set_pte = xen_set_pte; pv_mmu_ops.set_pmd = xen_set_pmd; pv_mmu_ops.set_pud = xen_set_pud; -- cgit v1.2.3-70-g09d2 From a867db10e89e12a3d97dedafdd411aa1527a6540 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 23 Sep 2011 16:32:47 -0400 Subject: xen/p2m: Make debug/xen/mmu/p2m visible again. We dropped a lot of the MMU debugfs in favour of using tracing API - but there is one which just provides mostly static information that was made invisible by this change. Bring it back. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/include/asm/xen/page.h | 3 --- arch/x86/xen/mmu.c | 14 -------------- arch/x86/xen/p2m.c | 35 ++++++++++++++++++++++++++++++++--- 3 files changed, 32 insertions(+), 20 deletions(-) (limited to 'arch/x86/xen') diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index 64a619d47d3..bc12c12299c 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -53,9 +53,6 @@ extern int m2p_remove_override(struct page *page, bool clear_pte); extern struct page *m2p_find_override(unsigned long mfn); extern unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn); -#ifdef CONFIG_XEN_DEBUG_FS -extern int p2m_dump_show(struct seq_file *m, void *v); -#endif static inline unsigned long pfn_to_mfn(unsigned long pfn) { unsigned long mfn; diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 3c9aecd09ed..4df0444b2ce 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -2362,17 +2362,3 @@ out: return err; } EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range); - -#ifdef CONFIG_XEN_DEBUG_FS -static int p2m_dump_open(struct inode *inode, struct file *filp) -{ - return single_open(filp, p2m_dump_show, NULL); -} - -static const struct file_operations p2m_dump_fops = { - .open = p2m_dump_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; -#endif /* CONFIG_XEN_DEBUG_FS */ diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 58efeb9d544..cc2f8dcf8dd 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -782,8 +782,9 @@ unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn) EXPORT_SYMBOL_GPL(m2p_find_override_pfn); #ifdef CONFIG_XEN_DEBUG_FS - -int p2m_dump_show(struct seq_file *m, void *v) +#include +#include "debugfs.h" +static int p2m_dump_show(struct seq_file *m, void *v) { static const char * const level_name[] = { "top", "middle", "entry", "abnormal" }; @@ -856,4 +857,32 @@ int p2m_dump_show(struct seq_file *m, void *v) #undef TYPE_PFN #undef TYPE_UNKNOWN } -#endif + +static int p2m_dump_open(struct inode *inode, struct file *filp) +{ + return single_open(filp, p2m_dump_show, NULL); +} + +static const struct file_operations p2m_dump_fops = { + .open = p2m_dump_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static struct dentry *d_mmu_debug; + +static int __init xen_p2m_debugfs(void) +{ + struct dentry *d_xen = xen_init_debugfs(); + + if (d_xen == NULL) + return -ENOMEM; + + d_mmu_debug = debugfs_create_dir("mmu", d_xen); + + debugfs_create_file("p2m", 0600, d_mmu_debug, NULL, &p2m_dump_fops); + return 0; +} +fs_initcall(xen_p2m_debugfs); +#endif /* CONFIG_XEN_DEBUG_FS */ -- cgit v1.2.3-70-g09d2 From 0f4b49eaf25e661fbe63a5370b7781166b34d616 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 23 Sep 2011 17:36:07 -0400 Subject: xen/p2m: Use SetPagePrivate and its friends for M2P overrides. We use the page->private field and hence should use the proper macros and set proper bits. Also WARN_ON in case somebody tries to overwrite our data. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/p2m.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'arch/x86/xen') diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index cc2f8dcf8dd..6e56b65edaf 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -692,8 +692,9 @@ int m2p_add_override(unsigned long mfn, struct page *page, bool clear_pte) "m2p_add_override: pfn %lx not mapped", pfn)) return -EINVAL; } - - page->private = mfn; + WARN_ON(PagePrivate(page)); + SetPagePrivate(page); + set_page_private(page, mfn); page->index = pfn_to_mfn(pfn); if (unlikely(!set_phys_to_machine(pfn, FOREIGN_FRAME(mfn)))) @@ -736,7 +737,8 @@ int m2p_remove_override(struct page *page, bool clear_pte) list_del(&page->lru); spin_unlock_irqrestore(&m2p_override_lock, flags); set_phys_to_machine(pfn, page->index); - + WARN_ON(!PagePrivate(page)); + ClearPagePrivate(page); if (clear_pte && !PageHighMem(page)) set_pte_at(&init_mm, address, ptep, pfn_pte(pfn, PAGE_KERNEL)); @@ -758,7 +760,7 @@ struct page *m2p_find_override(unsigned long mfn) spin_lock_irqsave(&m2p_override_lock, flags); list_for_each_entry(p, bucket, lru) { - if (p->private == mfn) { + if (page_private(p) == mfn) { ret = p; break; } -- cgit v1.2.3-70-g09d2 From 0930bba674e248b921ea659b036ff02564e5a5f4 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Thu, 29 Sep 2011 11:57:56 +0100 Subject: xen: modify kernel mappings corresponding to granted pages If we want to use granted pages for AIO, changing the mappings of a user vma and the corresponding p2m is not enough, we also need to update the kernel mappings accordingly. Currently this is only needed for pages that are created for user usages through /dev/xen/gntdev. As in, pages that have been in use by the kernel and use the P2M will not need this special mapping. However there are no guarantees that in the future the kernel won't start accessing pages through the 1:1 even for internal usage. In order to avoid the complexity of dealing with highmem, we allocated the pages lowmem. We issue a HYPERVISOR_grant_table_op right away in m2p_add_override and we remove the mappings using another HYPERVISOR_grant_table_op in m2p_remove_override. Considering that m2p_add_override and m2p_remove_override are called once per page we use multicalls and hypercall batching. Use the kmap_op pointer directly as argument to do the mapping as it is guaranteed to be present up until the unmapping is done. Before issuing any unmapping multicalls, we need to make sure that the mapping has already being done, because we need the kmap->handle to be set correctly. Signed-off-by: Stefano Stabellini [v1: Removed GRANT_FRAME_BIT usage] Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/include/asm/xen/page.h | 3 +- arch/x86/xen/p2m.c | 76 ++++++++++++++++++++++++++++++++----- drivers/block/xen-blkback/blkback.c | 2 +- drivers/xen/gntdev.c | 32 +++++++++++++++- drivers/xen/grant-table.c | 6 +-- include/xen/grant_table.h | 1 + 6 files changed, 104 insertions(+), 16 deletions(-) (limited to 'arch/x86/xen') diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index bc12c12299c..3138d33b894 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -12,6 +12,7 @@ #include #include +#include #include /* Xen machine address */ @@ -48,7 +49,7 @@ extern unsigned long set_phys_range_identity(unsigned long pfn_s, unsigned long pfn_e); extern int m2p_add_override(unsigned long mfn, struct page *page, - bool clear_pte); + struct gnttab_map_grant_ref *kmap_op); extern int m2p_remove_override(struct page *page, bool clear_pte); extern struct page *m2p_find_override(unsigned long mfn); extern unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn); diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 6e56b65edaf..a8ee9a45c35 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -161,7 +161,9 @@ #include #include #include +#include +#include "multicalls.h" #include "xen-ops.h" static void __init m2p_override_init(void); @@ -676,7 +678,8 @@ static unsigned long mfn_hash(unsigned long mfn) } /* Add an MFN override for a particular page */ -int m2p_add_override(unsigned long mfn, struct page *page, bool clear_pte) +int m2p_add_override(unsigned long mfn, struct page *page, + struct gnttab_map_grant_ref *kmap_op) { unsigned long flags; unsigned long pfn; @@ -700,9 +703,20 @@ int m2p_add_override(unsigned long mfn, struct page *page, bool clear_pte) if (unlikely(!set_phys_to_machine(pfn, FOREIGN_FRAME(mfn)))) return -ENOMEM; - if (clear_pte && !PageHighMem(page)) - /* Just zap old mapping for now */ - pte_clear(&init_mm, address, ptep); + if (kmap_op != NULL) { + if (!PageHighMem(page)) { + struct multicall_space mcs = + xen_mc_entry(sizeof(*kmap_op)); + + MULTI_grant_table_op(mcs.mc, + GNTTABOP_map_grant_ref, kmap_op, 1); + + xen_mc_issue(PARAVIRT_LAZY_MMU); + } + /* let's use dev_bus_addr to record the old mfn instead */ + kmap_op->dev_bus_addr = page->index; + page->index = (unsigned long) kmap_op; + } spin_lock_irqsave(&m2p_override_lock, flags); list_add(&page->lru, &m2p_overrides[mfn_hash(mfn)]); spin_unlock_irqrestore(&m2p_override_lock, flags); @@ -736,14 +750,56 @@ int m2p_remove_override(struct page *page, bool clear_pte) spin_lock_irqsave(&m2p_override_lock, flags); list_del(&page->lru); spin_unlock_irqrestore(&m2p_override_lock, flags); - set_phys_to_machine(pfn, page->index); WARN_ON(!PagePrivate(page)); ClearPagePrivate(page); - if (clear_pte && !PageHighMem(page)) - set_pte_at(&init_mm, address, ptep, - pfn_pte(pfn, PAGE_KERNEL)); - /* No tlb flush necessary because the caller already - * left the pte unmapped. */ + + if (clear_pte) { + struct gnttab_map_grant_ref *map_op = + (struct gnttab_map_grant_ref *) page->index; + set_phys_to_machine(pfn, map_op->dev_bus_addr); + if (!PageHighMem(page)) { + struct multicall_space mcs; + struct gnttab_unmap_grant_ref *unmap_op; + + /* + * It might be that we queued all the m2p grant table + * hypercalls in a multicall, then m2p_remove_override + * get called before the multicall has actually been + * issued. In this case handle is going to -1 because + * it hasn't been modified yet. + */ + if (map_op->handle == -1) + xen_mc_flush(); + /* + * Now if map_op->handle is negative it means that the + * hypercall actually returned an error. + */ + if (map_op->handle == GNTST_general_error) { + printk(KERN_WARNING "m2p_remove_override: " + "pfn %lx mfn %lx, failed to modify kernel mappings", + pfn, mfn); + return -1; + } + + mcs = xen_mc_entry( + sizeof(struct gnttab_unmap_grant_ref)); + unmap_op = mcs.args; + unmap_op->host_addr = map_op->host_addr; + unmap_op->handle = map_op->handle; + unmap_op->dev_bus_addr = 0; + + MULTI_grant_table_op(mcs.mc, + GNTTABOP_unmap_grant_ref, unmap_op, 1); + + xen_mc_issue(PARAVIRT_LAZY_MMU); + + set_pte_at(&init_mm, address, ptep, + pfn_pte(pfn, PAGE_KERNEL)); + __flush_tlb_single(address); + map_op->host_addr = 0; + } + } else + set_phys_to_machine(pfn, page->index); return 0; } diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 2330a9ad5e9..1540792b1e5 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -396,7 +396,7 @@ static int xen_blkbk_map(struct blkif_request *req, continue; ret = m2p_add_override(PFN_DOWN(map[i].dev_bus_addr), - blkbk->pending_page(pending_req, i), false); + blkbk->pending_page(pending_req, i), NULL); if (ret) { pr_alert(DRV_PFX "Failed to install M2P override for %lx (ret: %d)\n", (unsigned long)map[i].dev_bus_addr, ret); diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 7b9b1d1b75a..3e3603f3524 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -83,6 +83,7 @@ struct grant_map { struct ioctl_gntdev_grant_ref *grants; struct gnttab_map_grant_ref *map_ops; struct gnttab_unmap_grant_ref *unmap_ops; + struct gnttab_map_grant_ref *kmap_ops; struct page **pages; }; @@ -116,10 +117,12 @@ static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count) add->grants = kzalloc(sizeof(add->grants[0]) * count, GFP_KERNEL); add->map_ops = kzalloc(sizeof(add->map_ops[0]) * count, GFP_KERNEL); add->unmap_ops = kzalloc(sizeof(add->unmap_ops[0]) * count, GFP_KERNEL); + add->kmap_ops = kzalloc(sizeof(add->kmap_ops[0]) * count, GFP_KERNEL); add->pages = kzalloc(sizeof(add->pages[0]) * count, GFP_KERNEL); if (NULL == add->grants || NULL == add->map_ops || NULL == add->unmap_ops || + NULL == add->kmap_ops || NULL == add->pages) goto err; @@ -129,6 +132,7 @@ static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count) for (i = 0; i < count; i++) { add->map_ops[i].handle = -1; add->unmap_ops[i].handle = -1; + add->kmap_ops[i].handle = -1; } add->index = 0; @@ -142,6 +146,7 @@ err: kfree(add->grants); kfree(add->map_ops); kfree(add->unmap_ops); + kfree(add->kmap_ops); kfree(add); return NULL; } @@ -243,10 +248,35 @@ static int map_grant_pages(struct grant_map *map) gnttab_set_unmap_op(&map->unmap_ops[i], addr, map->flags, -1 /* handle */); } + } else { + /* + * Setup the map_ops corresponding to the pte entries pointing + * to the kernel linear addresses of the struct pages. + * These ptes are completely different from the user ptes dealt + * with find_grant_ptes. + */ + for (i = 0; i < map->count; i++) { + unsigned level; + unsigned long address = (unsigned long) + pfn_to_kaddr(page_to_pfn(map->pages[i])); + pte_t *ptep; + u64 pte_maddr = 0; + BUG_ON(PageHighMem(map->pages[i])); + + ptep = lookup_address(address, &level); + pte_maddr = arbitrary_virt_to_machine(ptep).maddr; + gnttab_set_map_op(&map->kmap_ops[i], pte_maddr, + map->flags | + GNTMAP_host_map | + GNTMAP_contains_pte, + map->grants[i].ref, + map->grants[i].domid); + } } pr_debug("map %d+%d\n", map->index, map->count); - err = gnttab_map_refs(map->map_ops, map->pages, map->count); + err = gnttab_map_refs(map->map_ops, use_ptemod ? map->kmap_ops : NULL, + map->pages, map->count); if (err) return err; diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 4f44b347b24..8c71ab80175 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -448,7 +448,8 @@ unsigned int gnttab_max_grant_frames(void) EXPORT_SYMBOL_GPL(gnttab_max_grant_frames); int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, - struct page **pages, unsigned int count) + struct gnttab_map_grant_ref *kmap_ops, + struct page **pages, unsigned int count) { int i, ret; pte_t *pte; @@ -488,8 +489,7 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, */ return -EOPNOTSUPP; } - ret = m2p_add_override(mfn, pages[i], - map_ops[i].flags & GNTMAP_contains_pte); + ret = m2p_add_override(mfn, pages[i], &kmap_ops[i]); if (ret) return ret; } diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index b1fab6b5b3e..6b99bfbd785 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -156,6 +156,7 @@ unsigned int gnttab_max_grant_frames(void); #define gnttab_map_vaddr(map) ((void *)(map.host_virt_addr)) int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, + struct gnttab_map_grant_ref *kmap_ops, struct page **pages, unsigned int count); int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, struct page **pages, unsigned int count); -- cgit v1.2.3-70-g09d2 From 5e287830136a8edb76e9f9c432b264d99833172f Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Thu, 29 Sep 2011 13:06:42 -0400 Subject: xen/enlighten: Fix compile warnings and set cx to known value. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We get: linux/arch/x86/xen/enlighten.c: In function ‘xen_start_kernel’: linux/arch/x86/xen/enlighten.c:226: warning: ‘cx’ may be used uninitialized in this function linux/arch/x86/xen/enlighten.c:240: note: ‘cx’ was declared here and the cx is really not set but passed in the xen_cpuid instruction which masks the value with returned masked_ecx from cpuid. This can potentially lead to invalid data being stored in cx. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/enlighten.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/xen') diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 2d69617950f..da8afd576a6 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -251,6 +251,7 @@ static void __init xen_init_cpuid_mask(void) ~((1 << X86_FEATURE_APIC) | /* disable local APIC */ (1 << X86_FEATURE_ACPI)); /* disable ACPI */ ax = 1; + cx = 0; xen_cpuid(&ax, &bx, &cx, &dx); xsave_mask = -- cgit v1.2.3-70-g09d2 From 8404877ee1cfdbc872e153fd89022f9e47f6f5a3 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Thu, 29 Sep 2011 13:09:34 -0400 Subject: xen/p2m/debugfs: Fix potential pointer exception. We could be referencing the last + 1 element of level_name[] array which would cause a pointer exception, because of the initial setup of lvl=4. [v1: No need to do this for type_name, pointed out by Ian Campbell] Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/p2m.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/xen') diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 58efeb9d544..2e3bf7a0732 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -786,7 +786,7 @@ EXPORT_SYMBOL_GPL(m2p_find_override_pfn); int p2m_dump_show(struct seq_file *m, void *v) { static const char * const level_name[] = { "top", "middle", - "entry", "abnormal" }; + "entry", "abnormal", "error"}; static const char * const type_name[] = { "identity", "missing", "pfn", "abnormal"}; #define TYPE_IDENTITY 0 -- cgit v1.2.3-70-g09d2 From a491dbef56f2aba42fb292067d4652d246627738 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Mon, 3 Oct 2011 12:35:26 -0400 Subject: xen/p2m/debugfs: Make type_name more obvious. Per Ian Campbell suggestion to defend against future breakage in case we expand the P2M values, incorporate the defines in the string array. Suggested-by: Ian Campbell Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/p2m.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/x86/xen') diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 2e3bf7a0732..795e003517e 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -787,12 +787,15 @@ int p2m_dump_show(struct seq_file *m, void *v) { static const char * const level_name[] = { "top", "middle", "entry", "abnormal", "error"}; - static const char * const type_name[] = { "identity", "missing", - "pfn", "abnormal"}; #define TYPE_IDENTITY 0 #define TYPE_MISSING 1 #define TYPE_PFN 2 #define TYPE_UNKNOWN 3 + static const char * const type_name[] = { + [TYPE_IDENTITY] = "identity", + [TYPE_MISSING] = "missing", + [TYPE_PFN] = "pfn", + [TYPE_UNKNOWN] = "abnormal"}; unsigned long pfn, prev_pfn_type = 0, prev_pfn_level = 0; unsigned int uninitialized_var(prev_level); unsigned int uninitialized_var(prev_type); -- cgit v1.2.3-70-g09d2