int LL_PROC_PROTO(proc_max_dirty_pages_in_mb)
{
int rc = 0;
if (!table->data || !table->maxlen || !*lenp || (*ppos && !write)) {
*lenp = 0;
return 0;
}
if (write) {
rc = lprocfs_write_frac_helper(buffer, *lenp,
(unsigned int *)table->data,
1 << (20 - PAGE_CACHE_SHIFT));
/* Don't allow them to let dirty pages exceed 90% of system
* memory and set a hard minimum of 4MB. */
if (obd_max_dirty_pages > ((totalram_pages / 10) * 9)) {
CERROR("Refusing to set max dirty pages to %u, which "
"is more than 90%% of available RAM; setting "
"to %lu\n", obd_max_dirty_pages,
((totalram_pages / 10) * 9));
obd_max_dirty_pages = ((totalram_pages / 10) * 9);
} else if (obd_max_dirty_pages < 4 << (20 - PAGE_CACHE_SHIFT)) {
obd_max_dirty_pages = 4 << (20 - PAGE_CACHE_SHIFT);
}
} else {
char buf[21];
int len;
len = lprocfs_read_frac_helper(buf, sizeof(buf),
*(unsigned int *)table->data,
1 << (20 - PAGE_CACHE_SHIFT));
if (len > *lenp)
len = *lenp;
buf[len] = '\0';
if (copy_to_user(buffer, buf, len))
return -EFAULT;
*lenp = len;
}
*ppos += *lenp;
return rc;
}
static int osc_wr_max_dirty_mb(struct file *file, const char *buffer,
unsigned long count, void *data)
{
struct obd_device *dev = data;
struct client_obd *cli = &dev->u.cli;
int pages_number, mult, rc;
mult = 1 << (20 - CFS_PAGE_SHIFT);
rc = lprocfs_write_frac_helper(buffer, count, &pages_number, mult);
if (rc)
return rc;
if (pages_number < 0 ||
pages_number > OSC_MAX_DIRTY_MB_MAX << (20 - CFS_PAGE_SHIFT) ||
pages_number > cfs_num_physpages / 4) /* 1/4 of RAM */
return -ERANGE;
client_obd_list_lock(&cli->cl_loi_list_lock);
cli->cl_dirty_max = (obd_count)(pages_number << CFS_PAGE_SHIFT);
osc_wake_cache_waiters(cli);
client_obd_list_unlock(&cli->cl_loi_list_lock);
return count;
}
