#include <linux/stringify.h>
#include <linux/swap.h>
#include <linux/device.h>
+#include <linux/mount.h>
+#include <linux/pseudo_fs.h>
+#include <linux/magic.h>
+#include <linux/balloon_compaction.h>
#include <asm/firmware.h>
#include <asm/hvcall.h>
#include <asm/mmu.h>
static unsigned long loaned_pages_target;
static unsigned long oom_freed_pages;
-static LIST_HEAD(cmm_page_list);
-static DEFINE_SPINLOCK(cmm_lock);
-
static DEFINE_MUTEX(hotplug_mutex);
static int hotplug_occurred; /* protected by the hotplug mutex */
static struct task_struct *cmm_thread_ptr;
+static struct balloon_dev_info b_dev_info;
static long plpar_page_set_loaned(struct page *page)
{
break;
}
- page = alloc_page(GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY |
- __GFP_NOMEMALLOC);
+ page = balloon_page_alloc();
if (!page)
break;
- spin_lock(&cmm_lock);
rc = plpar_page_set_loaned(page);
if (rc) {
pr_err("%s: Can not set page to loaned. rc=%ld\n", __func__, rc);
- spin_unlock(&cmm_lock);
__free_page(page);
break;
}
- list_add(&page->lru, &cmm_page_list);
+ balloon_page_enqueue(&b_dev_info, page);
atomic_long_inc(&loaned_pages);
adjust_managed_page_count(page, -1);
- spin_unlock(&cmm_lock);
nr--;
}
**/
static long cmm_free_pages(long nr)
{
- struct page *page, *tmp;
+ struct page *page;
cmm_dbg("Begin free of %ld pages.\n", nr);
- spin_lock(&cmm_lock);
- list_for_each_entry_safe(page, tmp, &cmm_page_list, lru) {
- if (!nr)
+ while (nr) {
+ page = balloon_page_dequeue(&b_dev_info);
+ if (!page)
break;
plpar_page_set_active(page);
- list_del(&page->lru);
adjust_managed_page_count(page, 1);
__free_page(page);
atomic_long_dec(&loaned_pages);
nr--;
}
- spin_unlock(&cmm_lock);
cmm_dbg("End request with %ld pages unfulfilled\n", nr);
return nr;
}
.priority = CMM_MEM_HOTPLUG_PRI
};
+#ifdef CONFIG_BALLOON_COMPACTION
+static struct vfsmount *balloon_mnt;
+
+static int cmm_init_fs_context(struct fs_context *fc)
+{
+ return init_pseudo(fc, PPC_CMM_MAGIC) ? 0 : -ENOMEM;
+}
+
+static struct file_system_type balloon_fs = {
+ .name = "ppc-cmm",
+ .init_fs_context = cmm_init_fs_context,
+ .kill_sb = kill_anon_super,
+};
+
+static int cmm_migratepage(struct balloon_dev_info *b_dev_info,
+ struct page *newpage, struct page *page,
+ enum migrate_mode mode)
+{
+ unsigned long flags;
+
+ /*
+ * loan/"inflate" the newpage first.
+ *
+ * We might race against the cmm_thread who might discover after our
+ * loan request that another page is to be unloaned. However, once
+ * the cmm_thread runs again later, this error will automatically
+ * be corrected.
+ */
+ if (plpar_page_set_loaned(newpage)) {
+ /* Unlikely, but possible. Tell the caller not to retry now. */
+ pr_err_ratelimited("%s: Cannot set page to loaned.", __func__);
+ return -EBUSY;
+ }
+
+ /* balloon page list reference */
+ get_page(newpage);
+
+ spin_lock_irqsave(&b_dev_info->pages_lock, flags);
+ balloon_page_insert(b_dev_info, newpage);
+ balloon_page_delete(page);
+ b_dev_info->isolated_pages--;
+ spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
+
+ /*
+ * activate/"deflate" the old page. We ignore any errors just like the
+ * other callers.
+ */
+ plpar_page_set_active(page);
+
+ /* balloon page list reference */
+ put_page(page);
+
+ return MIGRATEPAGE_SUCCESS;
+}
+
+static int cmm_balloon_compaction_init(void)
+{
+ int rc;
+
+ balloon_devinfo_init(&b_dev_info);
+ b_dev_info.migratepage = cmm_migratepage;
+
+ balloon_mnt = kern_mount(&balloon_fs);
+ if (IS_ERR(balloon_mnt)) {
+ rc = PTR_ERR(balloon_mnt);
+ balloon_mnt = NULL;
+ return rc;
+ }
+
+ b_dev_info.inode = alloc_anon_inode(balloon_mnt->mnt_sb);
+ if (IS_ERR(b_dev_info.inode)) {
+ rc = PTR_ERR(b_dev_info.inode);
+ b_dev_info.inode = NULL;
+ kern_unmount(balloon_mnt);
+ balloon_mnt = NULL;
+ return rc;
+ }
+
+ b_dev_info.inode->i_mapping->a_ops = &balloon_aops;
+ return 0;
+}
+static void cmm_balloon_compaction_deinit(void)
+{
+ if (b_dev_info.inode)
+ iput(b_dev_info.inode);
+ b_dev_info.inode = NULL;
+ kern_unmount(balloon_mnt);
+ balloon_mnt = NULL;
+}
+#else /* CONFIG_BALLOON_COMPACTION */
+static int cmm_balloon_compaction_init(void)
+{
+ return 0;
+}
+
+static void cmm_balloon_compaction_deinit(void)
+{
+}
+#endif /* CONFIG_BALLOON_COMPACTION */
+
/**
* cmm_init - Module initialization
*
if (!firmware_has_feature(FW_FEATURE_CMO))
return -EOPNOTSUPP;
- if ((rc = register_oom_notifier(&cmm_oom_nb)) < 0)
+ rc = cmm_balloon_compaction_init();
+ if (rc)
return rc;
+ rc = register_oom_notifier(&cmm_oom_nb);
+ if (rc < 0)
+ goto out_balloon_compaction;
+
if ((rc = register_reboot_notifier(&cmm_reboot_nb)))
goto out_oom_notifier;
unregister_reboot_notifier(&cmm_reboot_nb);
out_oom_notifier:
unregister_oom_notifier(&cmm_oom_nb);
+out_balloon_compaction:
+ cmm_balloon_compaction_deinit();
return rc;
}
unregister_memory_notifier(&cmm_mem_nb);
cmm_free_pages(atomic_long_read(&loaned_pages));
cmm_unregister_sysfs(&cmm_dev);
+ cmm_balloon_compaction_deinit();
}
/**
projects / linux-2.6-microblaze.git / blobdiff