diff options
Diffstat (limited to 'fs/proc/kcore.c')
| -rw-r--r-- | fs/proc/kcore.c | 179 |
1 files changed, 167 insertions, 12 deletions
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index fdde1cc78392..802de33d6341 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -17,10 +17,14 @@ #include <linux/elfcore.h> #include <linux/vmalloc.h> #include <linux/highmem.h> +#include <linux/bootmem.h> #include <linux/init.h> #include <asm/uaccess.h> #include <asm/io.h> #include <linux/list.h> +#include <linux/ioport.h> +#include <linux/mm.h> +#include <linux/memory.h> #include <asm/sections.h> #define CORE_STR "CORE" @@ -31,17 +35,6 @@ static struct proc_dir_entry *proc_root_kcore; -static int open_kcore(struct inode * inode, struct file * filp) -{ - return capable(CAP_SYS_RAWIO) ? 0 : -EPERM; -} - -static ssize_t read_kcore(struct file *, char __user *, size_t, loff_t *); - -static const struct file_operations proc_kcore_operations = { - .read = read_kcore, - .open = open_kcore, -}; #ifndef kc_vaddr_to_offset #define kc_vaddr_to_offset(v) ((v) - PAGE_OFFSET) @@ -61,6 +54,7 @@ struct memelfnote static LIST_HEAD(kclist_head); static DEFINE_RWLOCK(kclist_lock); +static int kcore_need_update = 1; void kclist_add(struct kcore_list *new, void *addr, size_t size, int type) @@ -99,6 +93,126 @@ static size_t get_kcore_size(int *nphdr, size_t *elf_buflen) return size + *elf_buflen; } +static void free_kclist_ents(struct list_head *head) +{ + struct kcore_list *tmp, *pos; + + list_for_each_entry_safe(pos, tmp, head, list) { + list_del(&pos->list); + kfree(pos); + } +} +/* + * Replace all KCORE_RAM information with passed list. + */ +static void __kcore_update_ram(struct list_head *list) +{ + struct kcore_list *tmp, *pos; + LIST_HEAD(garbage); + + write_lock(&kclist_lock); + if (kcore_need_update) { + list_for_each_entry_safe(pos, tmp, &kclist_head, list) { + if (pos->type == KCORE_RAM) + list_move(&pos->list, &garbage); + } + list_splice_tail(list, &kclist_head); + } else + list_splice(list, &garbage); + kcore_need_update = 0; + write_unlock(&kclist_lock); + + free_kclist_ents(&garbage); +} + + +#ifdef CONFIG_HIGHMEM +/* + * If no highmem, we can assume [0...max_low_pfn) continuous range of memory + * because memory hole is not as big as !HIGHMEM case. + * (HIGHMEM is special because part of memory is _invisible_ from the kernel.) + */ +static int kcore_update_ram(void) +{ + LIST_HEAD(head); + struct kcore_list *ent; + int ret = 0; + + ent = kmalloc(sizeof(*ent), GFP_KERNEL); + if (!ent) + return -ENOMEM; + ent->addr = (unsigned long)__va(0); + ent->size = max_low_pfn << PAGE_SHIFT; + ent->type = KCORE_RAM; + list_add(&ent->list, &head); + __kcore_update_ram(&head); + return ret; +} + +#else /* !CONFIG_HIGHMEM */ + +static int +kclist_add_private(unsigned long pfn, unsigned long nr_pages, void *arg) +{ + struct list_head *head = (struct list_head *)arg; + struct kcore_list *ent; + + ent = kmalloc(sizeof(*ent), GFP_KERNEL); + if (!ent) + return -ENOMEM; + ent->addr = (unsigned long)__va((pfn << PAGE_SHIFT)); + ent->size = nr_pages << PAGE_SHIFT; + + /* Sanity check: Can happen in 32bit arch...maybe */ + if (ent->addr < (unsigned long) __va(0)) + goto free_out; + + /* cut not-mapped area. ....from ppc-32 code. */ + if (ULONG_MAX - ent->addr < ent->size) + ent->size = ULONG_MAX - ent->addr; + + /* cut when vmalloc() area is higher than direct-map area */ + if (VMALLOC_START > (unsigned long)__va(0)) { + if (ent->addr > VMALLOC_START) + goto free_out; + if (VMALLOC_START - ent->addr < ent->size) + ent->size = VMALLOC_START - ent->addr; + } + + ent->type = KCORE_RAM; + list_add_tail(&ent->list, head); + return 0; +free_out: + kfree(ent); + return 1; +} + +static int kcore_update_ram(void) +{ + int nid, ret; + unsigned long end_pfn; + LIST_HEAD(head); + + /* Not inialized....update now */ + /* find out "max pfn" */ + end_pfn = 0; + for_each_node_state(nid, N_HIGH_MEMORY) { + unsigned long node_end; + node_end = NODE_DATA(nid)->node_start_pfn + + NODE_DATA(nid)->node_spanned_pages; + if (end_pfn < node_end) + end_pfn = node_end; + } + /* scan 0 to max_pfn */ + ret = walk_system_ram_range(0, end_pfn, &head, kclist_add_private); + if (ret) { + free_kclist_ents(&head); + return -ENOMEM; + } + __kcore_update_ram(&head); + return ret; +} +#endif /* CONFIG_HIGHMEM */ /*****************************************************************************/ /* @@ -373,6 +487,39 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos) return acc; } + +static int open_kcore(struct inode *inode, struct file *filp) +{ + if (!capable(CAP_SYS_RAWIO)) + return -EPERM; + if (kcore_need_update) + kcore_update_ram(); + return 0; +} + + +static const struct file_operations proc_kcore_operations = { + .read = read_kcore, + .open = open_kcore, +}; + +#ifdef CONFIG_MEMORY_HOTPLUG +/* just remember that we have to update kcore */ +static int __meminit kcore_callback(struct notifier_block *self, + unsigned long action, void *arg) +{ + switch (action) { + case MEM_ONLINE: + case MEM_OFFLINE: + write_lock(&kclist_lock); + kcore_need_update = 1; + write_unlock(&kclist_lock); + } + return NOTIFY_OK; +} +#endif + + static struct kcore_list kcore_vmalloc; #ifdef CONFIG_ARCH_PROC_KCORE_TEXT @@ -393,10 +540,18 @@ static void __init proc_kcore_text_init(void) static int __init proc_kcore_init(void) { - proc_root_kcore = proc_create("kcore", S_IRUSR, NULL, &proc_kcore_operations); + proc_root_kcore = proc_create("kcore", S_IRUSR, NULL, + &proc_kcore_operations); + /* Store text area if it's special */ proc_kcore_text_init(); + /* Store vmalloc area */ kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, VMALLOC_END - VMALLOC_START, KCORE_VMALLOC); + /* Store direct-map area from physical memory map */ + kcore_update_ram(); + hotplug_memory_notifier(kcore_callback, 0); + /* Other special area, area-for-module etc is arch specific. */ + return 0; } module_init(proc_kcore_init); |