Merge 4.4.211 into android-4.4-p

Changes in 4.4.211
	hidraw: Return EPOLLOUT from hidraw_poll
	HID: hidraw: Fix returning EPOLLOUT from hidraw_poll
	HID: hidraw, uhid: Always report EPOLLOUT
	rsi: add fix for crash during assertions
	cfg80211/mac80211: make ieee80211_send_layer2_update a public function
	mac80211: Do not send Layer 2 Update frame before authorization
	media: usb:zr364xx:Fix KASAN:null-ptr-deref Read in zr364xx_vidioc_querycap
	p54usb: Fix race between disconnect and firmware loading
	ALSA: line6: Fix write on zero-sized buffer
	ALSA: line6: Fix memory leak at line6_init_pcm() error path
	mm/page_alloc.c: calculate 'available' memory in a separate function
	xen: let alloc_xenballooned_pages() fail if not enough memory free
	wimax: i2400: fix memory leak
	wimax: i2400: Fix memory leak in i2400m_op_rfkill_sw_toggle
	ext4: fix use-after-free race with debug_want_extra_isize
	ext4: add more paranoia checking in ext4_expand_extra_isize handling
	dccp: Fix memleak in __feat_register_sp
	rtc: mt6397: fix alarm register overwrite
	iommu: Remove device link to group on failure
	gpio: Fix error message on out-of-range GPIO in lookup table
	hsr: reset network header when supervision frame is created
	cifs: Adjust indentation in smb2_open_file
	RDMA/srpt: Report the SCSI residual to the initiator
	scsi: enclosure: Fix stale device oops with hot replug
	scsi: sd: Clear sdkp->protection_type if disk is reformatted without PI
	platform/x86: asus-wmi: Fix keyboard brightness cannot be set to 0
	iio: imu: adis16480: assign bias value only if operation succeeded
	mei: fix modalias documentation
	clk: samsung: exynos5420: Preserve CPU clocks configuration during suspend/resume
	compat_ioctl: handle SIOCOUTQNSD
	tty: serial: imx: use the sg count from dma_map_sg
	tty: serial: pch_uart: correct usage of dma_unmap_sg
	media: exynos4-is: Fix recursive locking in isp_video_release()
	spi: atmel: fix handling of cs_change set on non-last xfer
	rtlwifi: Remove unnecessary NULL check in rtl_regd_init
	rtc: msm6242: Fix reading of 10-hour digit
	rseq/selftests: Turn off timeout setting
	hexagon: work around compiler crash
	ocfs2: call journal flush to mark journal as empty after journal recovery when mount
	ALSA: seq: Fix racy access for queue timer in proc read
	Fix built-in early-load Intel microcode alignment
	block: fix an integer overflow in logical block size
	USB: serial: simple: Add Motorola Solutions TETRA MTP3xxx and MTP85xx
	USB: serial: opticon: fix control-message timeouts
	USB: serial: suppress driver bind attributes
	USB: serial: ch341: handle unbound port at reset_resume
	USB: serial: io_edgeport: add missing active-port sanity check
	USB: serial: quatech2: handle unbound ports
	scsi: mptfusion: Fix double fetch bug in ioctl
	usb: core: hub: Improved device recognition on remote wakeup
	x86/efistub: Disable paging at mixed mode entry
	mm/page-writeback.c: avoid potential division by zero in wb_min_max_ratio()
	net: stmmac: 16KB buffer must be 16 byte aligned
	net: stmmac: Enable 16KB buffer size
	USB: serial: io_edgeport: use irqsave() in USB's complete callback
	USB: serial: io_edgeport: handle unbound ports on URB completion
	USB: serial: keyspan: handle unbound ports
	scsi: fnic: use kernel's '%pM' format option to print MAC
	scsi: fnic: fix invalid stack access
	arm64: dts: agilex/stratix10: fix pmu interrupt numbers
	netfilter: fix a use-after-free in mtype_destroy()
	batman-adv: Fix DAT candidate selection on little endian systems
	macvlan: use skb_reset_mac_header() in macvlan_queue_xmit()
	r8152: add missing endpoint sanity check
	tcp: fix marked lost packets not being retransmitted
	net: usb: lan78xx: limit size of local TSO packets
	xen/blkfront: Adjust indentation in xlvbd_alloc_gendisk
	cw1200: Fix a signedness bug in cw1200_load_firmware()
	cfg80211: check for set_wiphy_params
	scsi: esas2r: unlock on error in esas2r_nvram_read_direct()
	scsi: qla4xxx: fix double free bug
	scsi: bnx2i: fix potential use after free
	scsi: target: core: Fix a pr_debug() argument
	scsi: core: scsi_trace: Use get_unaligned_be*()
	perf probe: Fix wrong address verification
	regulator: ab8500: Remove SYSCLKREQ from enum ab8505_regulator_id
	Linux 4.4.211

Change-Id: I1e1bbb74e69936896e235fdeb290ff550e61903e
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

2 files changed, 45 insertions, 2 deletions

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index d2211e42b779..698806914be7 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -200,11 +200,11 @@ static void wb_min_max_ratio(struct bdi_writeback *wb,
 	if (this_bw < tot_bw) {
 		if (min) {
 			min *= this_bw;
-			do_div(min, tot_bw);
+			min = div64_ul(min, tot_bw);
 		}
 		if (max < 100) {
 			max *= this_bw;
-			do_div(max, tot_bw);
+			max = div64_ul(max, tot_bw);
 		}
 	}
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 5b7402abc1d6..173a6b57e7fd 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3662,6 +3662,49 @@ static inline void show_node(struct zone *zone)
 		printk("Node %d ", zone_to_nid(zone));
 }
 
+long si_mem_available(void)
+{
+	long available;
+	unsigned long pagecache;
+	unsigned long wmark_low = 0;
+	unsigned long pages[NR_LRU_LISTS];
+	struct zone *zone;
+	int lru;
+
+	for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++)
+		pages[lru] = global_page_state(NR_LRU_BASE + lru);
+
+	for_each_zone(zone)
+		wmark_low += zone->watermark[WMARK_LOW];
+
+	/*
+	 * Estimate the amount of memory available for userspace allocations,
+	 * without causing swapping.
+	 */
+	available = global_page_state(NR_FREE_PAGES) - totalreserve_pages;
+
+	/*
+	 * Not all the page cache can be freed, otherwise the system will
+	 * start swapping. Assume at least half of the page cache, or the
+	 * low watermark worth of cache, needs to stay.
+	 */
+	pagecache = pages[LRU_ACTIVE_FILE] + pages[LRU_INACTIVE_FILE];
+	pagecache -= min(pagecache / 2, wmark_low);
+	available += pagecache;
+
+	/*
+	 * Part of the reclaimable slab consists of items that are in use,
+	 * and cannot be freed. Cap this estimate at the low watermark.
+	 */
+	available += global_page_state(NR_SLAB_RECLAIMABLE) -
+		     min(global_page_state(NR_SLAB_RECLAIMABLE) / 2, wmark_low);
+
+	if (available < 0)
+		available = 0;
+	return available;
+}
+EXPORT_SYMBOL_GPL(si_mem_available);
+
 void si_meminfo(struct sysinfo *val)
 {
 	val->totalram = totalram_pages;