Introduce flags for reserve_bootmem()

This patchset adds a flags variable to reserve_bootmem() and uses the
BOOTMEM_EXCLUSIVE flag in crashkernel reservation code to detect collisions
between crashkernel area and already used memory.

This patch:

Change the reserve_bootmem() function to accept a new flag BOOTMEM_EXCLUSIVE.
If that flag is set, the function returns with -EBUSY if the memory already
has been reserved in the past.  This is to avoid conflicts.

Because that code runs before SMP initialisation, there's no race condition
inside reserve_bootmem_core().

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

7 files changed, 26 insertions, 18 deletions

diff --git a/arch/x86/kernel/mpparse_32.c b/arch/x86/kernel/mpparse_32.c
index 67009cdd5eca..f349e68e45a0 100644
--- a/arch/x86/kernel/mpparse_32.c
+++ b/arch/x86/kernel/mpparse_32.c
@@ -736,7 +736,8 @@ static int __init smp_scan_config (unsigned long base, unsigned long length)
                         smp_found_config = 1;
                         printk(KERN_INFO "found SMP MP-table at [%p] %08lx\n",
                                 mpf, virt_to_phys(mpf));
-                        reserve_bootmem(virt_to_phys(mpf), PAGE_SIZE);
+                        reserve_bootmem(virt_to_phys(mpf), PAGE_SIZE,
+                                        BOOTMEM_DEFAULT);
                         if (mpf->mpf_physptr) {
                                 /*
                                  * We cannot access to MPC table to compute
@@ -751,7 +752,8 @@ static int __init smp_scan_config (unsigned long base, unsigned long length)
                                 unsigned long end = max_low_pfn * PAGE_SIZE;
                                 if (mpf->mpf_physptr + size > end)
                                         size = end - mpf->mpf_physptr;
-                                reserve_bootmem(mpf->mpf_physptr, size);
+                                reserve_bootmem(mpf->mpf_physptr, size,
+                                                BOOTMEM_DEFAULT);
                         }
 
                         mpf_found = mpf;
diff --git a/arch/x86/kernel/setup_32.c b/arch/x86/kernel/setup_32.c
index 62adc5f20be5..d1d8c347cc0b 100644
--- a/arch/x86/kernel/setup_32.c
+++ b/arch/x86/kernel/setup_32.c
@@ -390,7 +390,7 @@ static void __init reserve_ebda_region(void)
         unsigned int addr;
         addr = get_bios_ebda();
         if (addr)
-                reserve_bootmem(addr, PAGE_SIZE);
+                reserve_bootmem(addr, PAGE_SIZE, BOOTMEM_DEFAULT);
 }
 
 #ifndef CONFIG_NEED_MULTIPLE_NODES
@@ -484,7 +484,8 @@ static void __init reserve_crashkernel(void)
                                         (unsigned long)(total_mem >> 20));
                         crashk_res.start = crash_base;
                         crashk_res.end   = crash_base + crash_size - 1;
-                        reserve_bootmem(crash_base, crash_size);
+                        reserve_bootmem(crash_base, crash_size,
+                                        BOOTMEM_DEFAULT);
                 } else
                         printk(KERN_INFO "crashkernel reservation failed - "
                                         "you have to specify a base address\n");
@@ -525,7 +526,7 @@ static void __init reserve_initrd(void)
         }
         if (ramdisk_end <= end_of_lowmem) {
                 /* All in lowmem, easy case */
-                reserve_bootmem(ramdisk_image, ramdisk_size);
+                reserve_bootmem(ramdisk_image, ramdisk_size, BOOTMEM_DEFAULT);
                 initrd_start = ramdisk_image + PAGE_OFFSET;
                 initrd_end = initrd_start+ramdisk_size;
                 return;
@@ -536,7 +537,7 @@ static void __init reserve_initrd(void)
 
         /* Note: this includes all the lowmem currently occupied by
            the initrd, we rely on that fact to keep the data intact. */
-        reserve_bootmem(ramdisk_here, ramdisk_size);
+        reserve_bootmem(ramdisk_here, ramdisk_size, BOOTMEM_DEFAULT);
         initrd_start = ramdisk_here + PAGE_OFFSET;
         initrd_end   = initrd_start + ramdisk_size;
 
@@ -606,13 +607,14 @@ void __init setup_bootmem_allocator(void)
          * bootmem allocator with an invalid RAM area.
          */
         reserve_bootmem(__pa_symbol(_text), (PFN_PHYS(min_low_pfn) +
-                         bootmap_size + PAGE_SIZE-1) - __pa_symbol(_text));
+                         bootmap_size + PAGE_SIZE-1) - __pa_symbol(_text),
+                         BOOTMEM_DEFAULT);
 
         /*
          * reserve physical page 0 - it's a special BIOS page on many boxes,
          * enabling clean reboots, SMP operation, laptop functions.
          */
-        reserve_bootmem(0, PAGE_SIZE);
+        reserve_bootmem(0, PAGE_SIZE, BOOTMEM_DEFAULT);
 
         /* reserve EBDA region, it's a 4K region */
         reserve_ebda_region();
@@ -622,7 +624,7 @@ void __init setup_bootmem_allocator(void)
        unless you have no PS/2 mouse plugged in. */
         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
             boot_cpu_data.x86 == 6)
-             reserve_bootmem(0xa0000 - 4096, 4096);
+             reserve_bootmem(0xa0000 - 4096, 4096, BOOTMEM_DEFAULT);
 
 #ifdef CONFIG_SMP
         /*
@@ -630,7 +632,7 @@ void __init setup_bootmem_allocator(void)
          * FIXME: Don't need the extra page at 4K, but need to fix
          * trampoline before removing it. (see the GDT stuff)
          */
-        reserve_bootmem(PAGE_SIZE, PAGE_SIZE);
+        reserve_bootmem(PAGE_SIZE, PAGE_SIZE, BOOTMEM_DEFAULT);
 #endif
 #ifdef CONFIG_ACPI_SLEEP
         /*
diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c
index c8939dfddfba..8345c3b12f05 100644
--- a/arch/x86/kernel/setup_64.c
+++ b/arch/x86/kernel/setup_64.c
@@ -189,7 +189,7 @@ contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
         bootmap_size = init_bootmem(bootmap >> PAGE_SHIFT, end_pfn);
         e820_register_active_regions(0, start_pfn, end_pfn);
         free_bootmem_with_active_regions(0, end_pfn);
-        reserve_bootmem(bootmap, bootmap_size);
+        reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
 }
 #endif
 
@@ -238,7 +238,8 @@ static void __init reserve_crashkernel(void)
                                         (unsigned long)(free_mem >> 20));
                         crashk_res.start = crash_base;
                         crashk_res.end   = crash_base + crash_size - 1;
-                        reserve_bootmem(crash_base, crash_size);
+                        reserve_bootmem(crash_base, crash_size,
+                                        BOOTMEM_DEFAULT);
                 } else
                         printk(KERN_INFO "crashkernel reservation failed - "
                                         "you have to specify a base address\n");
diff --git a/arch/x86/mm/discontig_32.c b/arch/x86/mm/discontig_32.c
index 04b1d20e2613..c394ca0720b8 100644
--- a/arch/x86/mm/discontig_32.c
+++ b/arch/x86/mm/discontig_32.c
@@ -391,7 +391,8 @@ unsigned long __init setup_memory(void)
 void __init numa_kva_reserve(void)
 {
         if (kva_pages)
-                reserve_bootmem(PFN_PHYS(kva_start_pfn), PFN_PHYS(kva_pages));
+                reserve_bootmem(PFN_PHYS(kva_start_pfn), PFN_PHYS(kva_pages),
+                                BOOTMEM_DEFAULT);
 }
 
 void __init zone_sizes_init(void)
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 9b61c75a2355..5fe880fc305d 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -644,9 +644,9 @@ void __init reserve_bootmem_generic(unsigned long phys, unsigned len)
 
         /* Should check here against the e820 map to avoid double free */
 #ifdef CONFIG_NUMA
-        reserve_bootmem_node(NODE_DATA(nid), phys, len);
+        reserve_bootmem_node(NODE_DATA(nid), phys, len, BOOTMEM_DEFAULT);
 #else
-        reserve_bootmem(phys, len);
+        reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
 #endif
         if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
                 dma_reserve += len / PAGE_SIZE;
diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c
index 5a02bf4c91ec..1aecc658cd7d 100644
--- a/arch/x86/mm/numa_64.c
+++ b/arch/x86/mm/numa_64.c
@@ -238,9 +238,10 @@ void __init setup_node_bootmem(int nodeid, unsigned long start,
 
         free_bootmem_with_active_regions(nodeid, end);
 
-        reserve_bootmem_node(NODE_DATA(nodeid), nodedata_phys, pgdat_size);
+        reserve_bootmem_node(NODE_DATA(nodeid), nodedata_phys, pgdat_size,
+                        BOOTMEM_DEFAULT);
         reserve_bootmem_node(NODE_DATA(nodeid), bootmap_start,
-                             bootmap_pages<<PAGE_SHIFT);
+                        bootmap_pages<<PAGE_SHIFT, BOOTMEM_DEFAULT);
 #ifdef CONFIG_ACPI_NUMA
         srat_reserve_add_area(nodeid);
 #endif
diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c
index 65416f843e59..ecd91ea8a8ae 100644
--- a/arch/x86/mm/srat_64.c
+++ b/arch/x86/mm/srat_64.c
@@ -488,7 +488,8 @@ void __init srat_reserve_add_area(int nodeid)
                 printk(KERN_INFO "SRAT: This will cost you %Lu MB of "
                                 "pre-allocated memory.\n", (unsigned long long)total_mb);
                 reserve_bootmem_node(NODE_DATA(nodeid), nodes_add[nodeid].start,
-                               nodes_add[nodeid].end - nodes_add[nodeid].start);
+                               nodes_add[nodeid].end - nodes_add[nodeid].start,
+                               BOOTMEM_DEFAULT);
         }
 }