asmlinkage int sunos_brk(u32 baddr)
{
int freepages, retval = -ENOMEM;
unsigned long rlim;
unsigned long newbrk, oldbrk, brk = (unsigned long) baddr;
down_write(¤t->mm->mmap_sem);
if (brk < current->mm->end_code)
goto out;
newbrk = PAGE_ALIGN(brk);
oldbrk = PAGE_ALIGN(current->mm->brk);
retval = 0;
if (oldbrk == newbrk) {
current->mm->brk = brk;
goto out;
}
/* Always allow shrinking brk. */
if (brk <= current->mm->brk) {
current->mm->brk = brk;
do_munmap(current->mm, newbrk, oldbrk-newbrk);
goto out;
}
/* Check against rlimit and stack.. */
retval = -ENOMEM;
rlim = current->rlim[RLIMIT_DATA].rlim_cur;
if (rlim >= RLIM_INFINITY)
rlim = ~0;
if (brk - current->mm->end_code > rlim)
goto out;
/* Check against existing mmap mappings. */
if (find_vma_intersection(current->mm, oldbrk, newbrk+PAGE_SIZE))
goto out;
/* stupid algorithm to decide if we have enough memory: while
* simple, it hopefully works in most obvious cases.. Easy to
* fool it, but this should catch most mistakes.
*/
freepages = get_page_cache_size();
freepages >>= 1;
freepages += nr_free_pages();
freepages += nr_swap_pages;
freepages -= num_physpages >> 4;
freepages -= (newbrk-oldbrk) >> PAGE_SHIFT;
if (freepages < 0)
goto out;
/* Ok, we have probably got enough memory - let it rip. */
current->mm->brk = brk;
do_brk(oldbrk, newbrk-oldbrk);
retval = 0;
out:
up_write(¤t->mm->mmap_sem);
return retval;
}
/*
* Check that a process has enough memory to allocate a new virtual
* mapping. 0 means there is enough memory for the allocation to
* succeed and -ENOMEM implies there is not.
*
* We currently support three overcommit policies, which are set via the
* vm.overcommit_memory sysctl. See Documentation/vm/overcommit-accounting
*/
static int dummy_vm_enough_memory(long pages)
{
unsigned long free, allowed;
vm_acct_memory(pages);
/*
* Sometimes we want to use more memory than we have
*/
if (sysctl_overcommit_memory == OVERCOMMIT_ALWAYS)
return 0;
if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
free = get_page_cache_size();
free += nr_free_pages();
free += nr_swap_pages;
/*
* Any slabs which are created with the
* SLAB_RECLAIM_ACCOUNT flag claim to have contents
* which are reclaimable, under pressure. The dentry
* cache and most inode caches should fall into this
*/
free += atomic_read(&slab_reclaim_pages);
/*
* Leave the last 3% for root
*/
if (current->euid)
free -= free / 32;
if (free > pages)
return 0;
vm_unacct_memory(pages);
return -ENOMEM;
}
allowed = (totalram_pages - hugetlb_total_pages())
* sysctl_overcommit_ratio / 100;
allowed += total_swap_pages;
if (atomic_read(&vm_committed_space) < allowed)
return 0;
vm_unacct_memory(pages);
return -ENOMEM;
}
/*
* Check that a process has enough memory to allocate a new virtual
* mapping. 0 means there is enough memory for the allocation to
* succeed and -ENOMEM implies there is not.
*
* We currently support three overcommit policies, which are set via the
* vm.overcommit_memory sysctl. See Documentation/vm/overcommit-accounting
*
* Strict overcommit modes added 2002 Feb 26 by Alan Cox.
* Additional code 2002 Jul 20 by Robert Love.
*/
int cap_vm_enough_memory(long pages)
{
unsigned long free, allowed;
vm_acct_memory(pages);
/*
* Sometimes we want to use more memory than we have
*/
if (sysctl_overcommit_memory == OVERCOMMIT_ALWAYS)
return 0;
if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
unsigned long n;
free = get_page_cache_size();
free += nr_swap_pages;
/*
* Any slabs which are created with the
* SLAB_RECLAIM_ACCOUNT flag claim to have contents
* which are reclaimable, under pressure. The dentry
* cache and most inode caches should fall into this
*/
free += atomic_read(&slab_reclaim_pages);
/*
* Leave the last 3% for root
*/
if (!capable(CAP_SYS_ADMIN))
free -= free / 32;
if (free > pages)
return 0;
/*
* nr_free_pages() is very expensive on large systems,
* only call if we're about to fail.
*/
n = nr_free_pages();
if (!capable(CAP_SYS_ADMIN))
n -= n / 32;
free += n;
if (free > pages)
return 0;
vm_unacct_memory(pages);
return -ENOMEM;
}
allowed = (totalram_pages - hugetlb_total_pages())
* sysctl_overcommit_ratio / 100;
/*
* Leave the last 3% for root
*/
if (!capable(CAP_SYS_ADMIN))
allowed -= allowed / 32;
allowed += total_swap_pages;
if (atomic_read(&vm_committed_space) < allowed)
return 0;
vm_unacct_memory(pages);
return -ENOMEM;
}
static int meminfo_read_proc(char *page, char **start, off_t off,
int count, int *eof, void *data)
{
struct sysinfo i;
int len;
struct page_state ps;
unsigned long inactive;
unsigned long active;
unsigned long free;
unsigned long committed;
unsigned long allowed;
struct vmalloc_info vmi;
long cached;
get_page_state(&ps);
get_zone_counts(&active, &inactive, &free);
/*
* display in kilobytes.
*/
#define K(x) ((x) << (PAGE_SHIFT - 10))
si_meminfo(&i);
si_swapinfo(&i);
committed = atomic_read(&vm_committed_space);
allowed = ((totalram_pages - hugetlb_total_pages())
* sysctl_overcommit_ratio / 100) + total_swap_pages;
cached = get_page_cache_size() - total_swapcache_pages - i.bufferram;
if (cached < 0)
cached = 0;
get_vmalloc_info(&vmi);
/*
* Tagged format, for easy grepping and expansion.
*/
len = sprintf(page,
"MemTotal: %8lu kB\n"
"MemFree: %8lu kB\n"
"Buffers: %8lu kB\n"
"Cached: %8lu kB\n"
"SwapCached: %8lu kB\n"
"Active: %8lu kB\n"
"Inactive: %8lu kB\n"
"HighTotal: %8lu kB\n"
"HighFree: %8lu kB\n"
"LowTotal: %8lu kB\n"
"LowFree: %8lu kB\n"
"SwapTotal: %8lu kB\n"
"SwapFree: %8lu kB\n"
"Dirty: %8lu kB\n"
"Writeback: %8lu kB\n"
"Mapped: %8lu kB\n"
"Slab: %8lu kB\n"
"CommitLimit: %8lu kB\n"
"Committed_AS: %8lu kB\n"
"PageTables: %8lu kB\n"
"VmallocTotal: %8lu kB\n"
"VmallocUsed: %8lu kB\n"
"VmallocChunk: %8lu kB\n",
K(i.totalram),
K(i.freeram),
K(i.bufferram),
K(cached),
K(total_swapcache_pages),
K(active),
K(inactive),
K(i.totalhigh),
K(i.freehigh),
K(i.totalram-i.totalhigh),
K(i.freeram-i.freehigh),
K(i.totalswap),
K(i.freeswap),
K(ps.nr_dirty),
K(ps.nr_writeback),
K(ps.nr_mapped),
K(ps.nr_slab),
K(allowed),
K(committed),
K(ps.nr_page_table_pages),
(unsigned long)VMALLOC_TOTAL >> 10,
vmi.used >> 10,
vmi.largest_chunk >> 10
);
len += hugetlb_report_meminfo(page + len);
return proc_calc_metrics(page, start, off, count, eof, len);
#undef K
}
