* Safe accesses to vmalloc/direct-mapped discontiguous areas, Kanoj Sarcar <kanoj@sgi.com>
*/
-#include <linux/config.h>
#include <linux/mm.h>
#include <linux/proc_fs.h>
#include <linux/user.h>
-#include <linux/a.out.h>
+#include <linux/capability.h>
#include <linux/elf.h>
#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/memory.h>
+#include <asm/sections.h>
+#define CORE_STR "CORE"
-static int open_kcore(struct inode * inode, struct file * filp)
-{
- return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
-}
+#ifndef ELF_CORE_EFLAGS
+#define ELF_CORE_EFLAGS 0
+#endif
-static ssize_t read_kcore(struct file *, char __user *, size_t, loff_t *);
+static struct proc_dir_entry *proc_root_kcore;
-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)
#define kc_offset_to_vaddr(o) ((o) + PAGE_OFFSET)
#endif
-#define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
-
/* An ELF note in memory */
struct memelfnote
{
void *data;
};
-static struct kcore_list *kclist;
+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)
+kclist_add(struct kcore_list *new, void *addr, size_t size, int type)
{
new->addr = (unsigned long)addr;
new->size = size;
+ new->type = type;
write_lock(&kclist_lock);
- new->next = kclist;
- kclist = new;
+ list_add_tail(&new->list, &kclist_head);
write_unlock(&kclist_lock);
}
*nphdr = 1; /* PT_NOTE */
size = 0;
- for (m=kclist; m; m=m->next) {
+ list_for_each_entry(m, &kclist_head, list) {
try = kc_vaddr_to_offset((size_t)m->addr + m->size);
if (try > size)
size = try;
}
*elf_buflen = sizeof(struct elfhdr) +
(*nphdr + 2)*sizeof(struct elf_phdr) +
- 3 * (sizeof(struct elf_note) + 4) +
- sizeof(struct elf_prstatus) +
- sizeof(struct elf_prpsinfo) +
- sizeof(struct task_struct);
+ 3 * ((sizeof(struct elf_note)) +
+ roundup(sizeof(CORE_STR), 4)) +
+ roundup(sizeof(struct elf_prstatus), 4) +
+ roundup(sizeof(struct elf_prpsinfo), 4) +
+ roundup(sizeof(struct task_struct), 4);
*elf_buflen = PAGE_ALIGN(*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/KCORE_VMEMMAP information with passed list.
+ */
+static void __kcore_update_ram(struct list_head *list)
+{
+ int nphdr;
+ size_t size;
+ 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
+ || pos->type == KCORE_VMEMMAP)
+ list_move(&pos->list, &garbage);
+ }
+ list_splice_tail(list, &kclist_head);
+ } else
+ list_splice(list, &garbage);
+ kcore_need_update = 0;
+ proc_root_kcore->size = get_kcore_size(&nphdr, &size);
+ 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 */
+
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+/* calculate vmemmap's address from given system ram pfn and register it */
+int get_sparsemem_vmemmap_info(struct kcore_list *ent, struct list_head *head)
+{
+ unsigned long pfn = __pa(ent->addr) >> PAGE_SHIFT;
+ unsigned long nr_pages = ent->size >> PAGE_SHIFT;
+ unsigned long start, end;
+ struct kcore_list *vmm, *tmp;
+
+
+ start = ((unsigned long)pfn_to_page(pfn)) & PAGE_MASK;
+ end = ((unsigned long)pfn_to_page(pfn + nr_pages)) - 1;
+ end = ALIGN(end, PAGE_SIZE);
+ /* overlap check (because we have to align page */
+ list_for_each_entry(tmp, head, list) {
+ if (tmp->type != KCORE_VMEMMAP)
+ continue;
+ if (start < tmp->addr + tmp->size)
+ if (end > tmp->addr)
+ end = tmp->addr;
+ }
+ if (start < end) {
+ vmm = kmalloc(sizeof(*vmm), GFP_KERNEL);
+ if (!vmm)
+ return 0;
+ vmm->addr = start;
+ vmm->size = end - start;
+ vmm->type = KCORE_VMEMMAP;
+ list_add_tail(&vmm->list, head);
+ }
+ return 1;
+
+}
+#else
+int get_sparsemem_vmemmap_info(struct kcore_list *ent, struct list_head *head)
+{
+ return 1;
+}
+
+#endif
+
+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);
+
+ if (!get_sparsemem_vmemmap_info(ent, head)) {
+ list_del(&ent->list);
+ goto free_out;
+ }
+
+ 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 */
/*****************************************************************************/
/*
int sz;
sz = sizeof(struct elf_note);
- sz += roundup(strlen(en->name), 4);
+ sz += roundup((strlen(en->name) + 1), 4);
sz += roundup(en->datasz, 4);
return sz;
#define DUMP_WRITE(addr,nr) do { memcpy(bufp,addr,nr); bufp += nr; } while(0)
- en.n_namesz = strlen(men->name);
+ en.n_namesz = strlen(men->name) + 1;
en.n_descsz = men->datasz;
en.n_type = men->type;
elf->e_entry = 0;
elf->e_phoff = sizeof(struct elfhdr);
elf->e_shoff = 0;
-#if defined(CONFIG_H8300)
- elf->e_flags = ELF_FLAGS;
-#else
- elf->e_flags = 0;
-#endif
+ elf->e_flags = ELF_CORE_EFLAGS;
elf->e_ehsize = sizeof(struct elfhdr);
elf->e_phentsize= sizeof(struct elf_phdr);
elf->e_phnum = nphdr;
nhdr->p_align = 0;
/* setup ELF PT_LOAD program header for every area */
- for (m=kclist; m; m=m->next) {
+ list_for_each_entry(m, &kclist_head, list) {
phdr = (struct elf_phdr *) bufp;
bufp += sizeof(struct elf_phdr);
offset += sizeof(struct elf_phdr);
nhdr->p_offset = offset;
/* set up the process status */
- notes[0].name = "CORE";
+ notes[0].name = CORE_STR;
notes[0].type = NT_PRSTATUS;
notes[0].datasz = sizeof(struct elf_prstatus);
notes[0].data = &prstatus;
bufp = storenote(¬es[0], bufp);
/* set up the process info */
- notes[1].name = "CORE";
+ notes[1].name = CORE_STR;
notes[1].type = NT_PRPSINFO;
notes[1].datasz = sizeof(struct elf_prpsinfo);
notes[1].data = &prpsinfo;
bufp = storenote(¬es[1], bufp);
/* set up the task structure */
- notes[2].name = "CORE";
+ notes[2].name = CORE_STR;
notes[2].type = NT_TASKSTRUCT;
notes[2].datasz = sizeof(struct task_struct);
notes[2].data = current;
unsigned long start;
read_lock(&kclist_lock);
- proc_root_kcore->size = size = get_kcore_size(&nphdr, &elf_buflen);
+ size = get_kcore_size(&nphdr, &elf_buflen);
+
if (buflen == 0 || *fpos >= size) {
read_unlock(&kclist_lock);
return 0;
tsz = elf_buflen - *fpos;
if (buflen < tsz)
tsz = buflen;
- elf_buf = kmalloc(elf_buflen, GFP_ATOMIC);
+ elf_buf = kzalloc(elf_buflen, GFP_ATOMIC);
if (!elf_buf) {
read_unlock(&kclist_lock);
return -ENOMEM;
}
- memset(elf_buf, 0, elf_buflen);
elf_kcore_store_hdr(elf_buf, nphdr, elf_buflen);
read_unlock(&kclist_lock);
if (copy_to_user(buffer, elf_buf + *fpos, tsz)) {
struct kcore_list *m;
read_lock(&kclist_lock);
- for (m=kclist; m; m=m->next) {
+ list_for_each_entry(m, &kclist_head, list) {
if (start >= m->addr && start < (m->addr+m->size))
break;
}
if (m == NULL) {
if (clear_user(buffer, tsz))
return -EFAULT;
- } else if ((start >= VMALLOC_START) && (start < VMALLOC_END)) {
+ } else if (is_vmalloc_or_module_addr((void *)start)) {
char * elf_buf;
- struct vm_struct *m;
- unsigned long curstart = start;
- unsigned long cursize = tsz;
- elf_buf = kmalloc(tsz, GFP_KERNEL);
+ elf_buf = kzalloc(tsz, GFP_KERNEL);
if (!elf_buf)
return -ENOMEM;
- memset(elf_buf, 0, tsz);
-
- read_lock(&vmlist_lock);
- for (m=vmlist; m && cursize; m=m->next) {
- unsigned long vmstart;
- unsigned long vmsize;
- unsigned long msize = m->size - PAGE_SIZE;
-
- if (((unsigned long)m->addr + msize) <
- curstart)
- continue;
- if ((unsigned long)m->addr > (curstart +
- cursize))
- break;
- vmstart = (curstart < (unsigned long)m->addr ?
- (unsigned long)m->addr : curstart);
- if (((unsigned long)m->addr + msize) >
- (curstart + cursize))
- vmsize = curstart + cursize - vmstart;
- else
- vmsize = (unsigned long)m->addr +
- msize - vmstart;
- curstart = vmstart + vmsize;
- cursize -= vmsize;
- /* don't dump ioremap'd stuff! (TA) */
- if (m->flags & VM_IOREMAP)
- continue;
- memcpy(elf_buf + (vmstart - start),
- (char *)vmstart, vmsize);
- }
- read_unlock(&vmlist_lock);
+ vread(elf_buf, (char *)start, tsz);
+ /* we have to zero-fill user buffer even if no read */
if (copy_to_user(buffer, elf_buf, tsz)) {
kfree(elf_buf);
return -EFAULT;
*/
if (n) {
if (clear_user(buffer + tsz - n,
- tsz - n))
+ n))
return -EFAULT;
}
} else {
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();
+ if (i_size_read(inode) != proc_root_kcore->size) {
+ mutex_lock(&inode->i_mutex);
+ i_size_write(inode, proc_root_kcore->size);
+ mutex_unlock(&inode->i_mutex);
+ }
+ 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
+static struct kcore_list kcore_text;
+/*
+ * If defined, special segment is used for mapping kernel text instead of
+ * direct-map area. We need to create special TEXT section.
+ */
+static void __init proc_kcore_text_init(void)
+{
+ kclist_add(&kcore_text, _stext, _end - _stext, KCORE_TEXT);
+}
+#else
+static void __init proc_kcore_text_init(void)
+{
+}
+#endif
+
+#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
+/*
+ * MODULES_VADDR has no intersection with VMALLOC_ADDR.
+ */
+struct kcore_list kcore_modules;
+static void __init add_modules_range(void)
+{
+ kclist_add(&kcore_modules, (void *)MODULES_VADDR,
+ MODULES_END - MODULES_VADDR, KCORE_VMALLOC);
+}
+#else
+static void __init add_modules_range(void)
+{
+}
+#endif
+
+static int __init proc_kcore_init(void)
+{
+ proc_root_kcore = proc_create("kcore", S_IRUSR, NULL,
+ &proc_kcore_operations);
+ if (!proc_root_kcore) {
+ printk(KERN_ERR "couldn't create /proc/kcore\n");
+ return 0; /* Always returns 0. */
+ }
+ /* 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);
+ add_modules_range();
+ /* Store direct-map area from physical memory map */
+ kcore_update_ram();
+ hotplug_memory_notifier(kcore_callback, 0);
+
+ return 0;
+}
+module_init(proc_kcore_init);