Merge branch 'akpm' (incoming from Andrew)

Merge more incoming from Andrew Morton:

 - Various fixes which were stalled or which I picked up recently

 - A large rotorooting of the AIO code.  Allegedly to improve
   performance but I don't really have good performance numbers (I might
   have lost the email) and I can't raise Kent today.  I held this out
   of 3.9 and we could give it another cycle if it's all too late/scary.

I ended up taking only the first two thirds of the AIO rotorooting.  I
left the percpu parts and the batch completion for later.  - Linus

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (33 commits)
  aio: don't include aio.h in sched.h
  aio: kill ki_retry
  aio: kill ki_key
  aio: give shared kioctx fields their own cachelines
  aio: kill struct aio_ring_info
  aio: kill batch allocation
  aio: change reqs_active to include unreaped completions
  aio: use cancellation list lazily
  aio: use flush_dcache_page()
  aio: make aio_read_evt() more efficient, convert to hrtimers
  wait: add wait_event_hrtimeout()
  aio: refcounting cleanup
  aio: make aio_put_req() lockless
  aio: do fget() after aio_get_req()
  aio: dprintk() -> pr_debug()
  aio: move private stuff out of aio.h
  aio: add kiocb_cancel()
  aio: kill return value of aio_complete()
  char: add aio_{read,write} to /dev/{null,zero}
  aio: remove retry-based AIO
  ...

18 files changed, 91 insertions, 27 deletions

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 2c644afbcdd4..1ccbe9482faa 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -28,6 +28,7 @@
 #include <linux/pfn.h>
 #include <linux/export.h>
 #include <linux/io.h>
+#include <linux/aio.h>
 
 #include <asm/uaccess.h>
 
@@ -627,6 +628,18 @@ static ssize_t write_null(struct file *file, const char __user *buf,
 	return count;
 }
 
+static ssize_t aio_read_null(struct kiocb *iocb, const struct iovec *iov,
+			     unsigned long nr_segs, loff_t pos)
+{
+	return 0;
+}
+
+static ssize_t aio_write_null(struct kiocb *iocb, const struct iovec *iov,
+			      unsigned long nr_segs, loff_t pos)
+{
+	return iov_length(iov, nr_segs);
+}
+
 static int pipe_to_null(struct pipe_inode_info *info, struct pipe_buffer *buf,
 			struct splice_desc *sd)
 {
@@ -670,6 +683,24 @@ static ssize_t read_zero(struct file *file, char __user *buf,
 	return written ? written : -EFAULT;
 }
 
+static ssize_t aio_read_zero(struct kiocb *iocb, const struct iovec *iov,
+			     unsigned long nr_segs, loff_t pos)
+{
+	size_t written = 0;
+	unsigned long i;
+	ssize_t ret;
+
+	for (i = 0; i < nr_segs; i++) {
+		ret = read_zero(iocb->ki_filp, iov[i].iov_base, iov[i].iov_len,
+				&pos);
+		if (ret < 0)
+			break;
+		written += ret;
+	}
+
+	return written ? written : -EFAULT;
+}
+
 static int mmap_zero(struct file *file, struct vm_area_struct *vma)
 {
 #ifndef CONFIG_MMU
@@ -738,6 +769,7 @@ static int open_port(struct inode *inode, struct file *filp)
 #define full_lseek      null_lseek
 #define write_zero	write_null
 #define read_full       read_zero
+#define aio_write_zero	aio_write_null
 #define open_mem	open_port
 #define open_kmem	open_mem
 #define open_oldmem	open_mem
@@ -766,6 +798,8 @@ static const struct file_operations null_fops = {
 	.llseek		= null_lseek,
 	.read		= read_null,
 	.write		= write_null,
+	.aio_read	= aio_read_null,
+	.aio_write	= aio_write_null,
 	.splice_write	= splice_write_null,
 };
 
@@ -782,6 +816,8 @@ static const struct file_operations zero_fops = {
 	.llseek		= zero_lseek,
 	.read		= read_zero,
 	.write		= write_zero,
+	.aio_read	= aio_read_zero,
+	.aio_write	= aio_write_zero,
 	.mmap		= mmap_zero,
 };
 
diff --git a/drivers/infiniband/hw/cxgb3/cxio_resource.c b/drivers/infiniband/hw/cxgb3/cxio_resource.c
index 31f9201b2980..c40088ecf9f3 100644
--- a/drivers/infiniband/hw/cxgb3/cxio_resource.c
+++ b/drivers/infiniband/hw/cxgb3/cxio_resource.c
@@ -62,13 +62,13 @@ static int __cxio_init_resource_fifo(struct kfifo *fifo,
 		kfifo_in(fifo, (unsigned char *) &entry, sizeof(u32));
 	if (random) {
 		j = 0;
-		random_bytes = random32();
+		random_bytes = prandom_u32();
 		for (i = 0; i < RANDOM_SIZE; i++)
 			rarray[i] = i + skip_low;
 		for (i = skip_low + RANDOM_SIZE; i < nr - skip_high; i++) {
 			if (j >= RANDOM_SIZE) {
 				j = 0;
-				random_bytes = random32();
+				random_bytes = prandom_u32();
 			}
 			idx = (random_bytes >> (j * 2)) & 0xF;
 			kfifo_in(fifo,
diff --git a/drivers/infiniband/hw/cxgb4/id_table.c b/drivers/infiniband/hw/cxgb4/id_table.c
index f95e5df30db2..0161ae6ad629 100644
--- a/drivers/infiniband/hw/cxgb4/id_table.c
+++ b/drivers/infiniband/hw/cxgb4/id_table.c
@@ -54,7 +54,7 @@ u32 c4iw_id_alloc(struct c4iw_id_table *alloc)
 
 	if (obj < alloc->max) {
 		if (alloc->flags & C4IW_ID_TABLE_F_RANDOM)
-			alloc->last += random32() % RANDOM_SKIP;
+			alloc->last += prandom_u32() % RANDOM_SKIP;
 		else
 			alloc->last = obj + 1;
 		if (alloc->last >= alloc->max)
@@ -88,7 +88,7 @@ int c4iw_id_table_alloc(struct c4iw_id_table *alloc, u32 start, u32 num,
 	alloc->start = start;
 	alloc->flags = flags;
 	if (flags & C4IW_ID_TABLE_F_RANDOM)
-		alloc->last = random32() % RANDOM_SKIP;
+		alloc->last = prandom_u32() % RANDOM_SKIP;
 	else
 		alloc->last = 0;
 	alloc->max  = num;
diff --git a/drivers/infiniband/hw/ipath/ipath_file_ops.c b/drivers/infiniband/hw/ipath/ipath_file_ops.c
index aed8afee56da..6d7f453b4d05 100644
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -40,6 +40,7 @@
 #include <linux/slab.h>
 #include <linux/highmem.h>
 #include <linux/io.h>
+#include <linux/aio.h>
 #include <linux/jiffies.h>
 #include <linux/cpu.h>
 #include <asm/pgtable.h>
diff --git a/drivers/infiniband/hw/mlx4/mad.c b/drivers/infiniband/hw/mlx4/mad.c
index 934792c477bc..4d599cedbb0b 100644
--- a/drivers/infiniband/hw/mlx4/mad.c
+++ b/drivers/infiniband/hw/mlx4/mad.c
@@ -93,7 +93,7 @@ static void __propagate_pkey_ev(struct mlx4_ib_dev *dev, int port_num,
 __be64 mlx4_ib_gen_node_guid(void)
 {
 #define NODE_GUID_HI	((u64) (((u64)IB_OPENIB_OUI) << 40))
-	return cpu_to_be64(NODE_GUID_HI | random32());
+	return cpu_to_be64(NODE_GUID_HI | prandom_u32());
 }
 
 __be64 mlx4_ib_get_new_demux_tid(struct mlx4_ib_demux_ctx *ctx)
diff --git a/drivers/infiniband/hw/qib/qib_file_ops.c b/drivers/infiniband/hw/qib/qib_file_ops.c
index 4f7aa301b3b1..b56c9428f3c5 100644
--- a/drivers/infiniband/hw/qib/qib_file_ops.c
+++ b/drivers/infiniband/hw/qib/qib_file_ops.c
@@ -39,7 +39,7 @@
 #include <linux/vmalloc.h>
 #include <linux/highmem.h>
 #include <linux/io.h>
-#include <linux/uio.h>
+#include <linux/aio.h>
 #include <linux/jiffies.h>
 #include <asm/pgtable.h>
 #include <linux/delay.h>
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
index 1ef880de3a41..3eceb61e3532 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -460,7 +460,7 @@ static int ipoib_cm_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *even
 		goto err_qp;
 	}
 
-	psn = random32() & 0xffffff;
+	psn = prandom_u32() & 0xffffff;
 	ret = ipoib_cm_modify_rx_qp(dev, cm_id, p->qp, psn);
 	if (ret)
 		goto err_modify;
diff --git a/drivers/net/ethernet/broadcom/cnic.c b/drivers/net/ethernet/broadcom/cnic.c
index 40649a8bf390..6b0dc131b20e 100644
--- a/drivers/net/ethernet/broadcom/cnic.c
+++ b/drivers/net/ethernet/broadcom/cnic.c
@@ -4085,7 +4085,7 @@ static int cnic_cm_alloc_mem(struct cnic_dev *dev)
 	if (!cp->csk_tbl)
 		return -ENOMEM;
 
-	port_id = random32();
+	port_id = prandom_u32();
 	port_id %= CNIC_LOCAL_PORT_RANGE;
 	if (cnic_init_id_tbl(&cp->csk_port_tbl, CNIC_LOCAL_PORT_RANGE,
 			     CNIC_LOCAL_PORT_MIN, port_id)) {
@@ -4145,7 +4145,7 @@ static int cnic_cm_init_bnx2_hw(struct cnic_dev *dev)
 {
 	u32 seed;
 
-	seed = random32();
+	seed = prandom_u32();
 	cnic_ctx_wr(dev, 45, 0, seed);
 	return 0;
 }
diff --git a/drivers/net/hamradio/baycom_epp.c b/drivers/net/hamradio/baycom_epp.c
index 49b8b58fc5c6..484f77ec2ce1 100644
--- a/drivers/net/hamradio/baycom_epp.c
+++ b/drivers/net/hamradio/baycom_epp.c
@@ -449,7 +449,7 @@ static int transmit(struct baycom_state *bc, int cnt, unsigned char stat)
 			if ((--bc->hdlctx.slotcnt) > 0)
 				return 0;
 			bc->hdlctx.slotcnt = bc->ch_params.slottime;
-			if ((random32() % 256) > bc->ch_params.ppersist)
+			if ((prandom_u32() % 256) > bc->ch_params.ppersist)
 				return 0;
 		}
 	}
diff --git a/drivers/net/hamradio/hdlcdrv.c b/drivers/net/hamradio/hdlcdrv.c
index a4a3516b6bbf..3169252613fa 100644
--- a/drivers/net/hamradio/hdlcdrv.c
+++ b/drivers/net/hamradio/hdlcdrv.c
@@ -389,7 +389,7 @@ void hdlcdrv_arbitrate(struct net_device *dev, struct hdlcdrv_state *s)
 	if ((--s->hdlctx.slotcnt) > 0)
 		return;
 	s->hdlctx.slotcnt = s->ch_params.slottime;
-	if ((random32() % 256) > s->ch_params.ppersist)
+	if ((prandom_u32() % 256) > s->ch_params.ppersist)
 		return;
 	start_tx(dev, s);
 }
diff --git a/drivers/net/hamradio/yam.c b/drivers/net/hamradio/yam.c
index b2d863f2ea42..0721e72f9299 100644
--- a/drivers/net/hamradio/yam.c
+++ b/drivers/net/hamradio/yam.c
@@ -638,7 +638,7 @@ static void yam_arbitrate(struct net_device *dev)
 	yp->slotcnt = yp->slot / 10;
 
 	/* is random > persist ? */
-	if ((random32() % 256) > yp->pers)
+	if ((prandom_u32() % 256) > yp->pers)
 		return;
 
 	yam_start_tx(dev, yp);
diff --git a/drivers/net/team/team_mode_random.c b/drivers/net/team/team_mode_random.c
index 9eabfaa22f3e..5ca14d463ba7 100644
--- a/drivers/net/team/team_mode_random.c
+++ b/drivers/net/team/team_mode_random.c
@@ -18,7 +18,7 @@
 
 static u32 random_N(unsigned int N)
 {
-	return reciprocal_divide(random32(), N);
+	return reciprocal_divide(prandom_u32(), N);
 }
 
 static bool rnd_transmit(struct team *team, struct sk_buff *skb)
diff --git a/drivers/net/wireless/brcm80211/brcmfmac/p2p.c b/drivers/net/wireless/brcm80211/brcmfmac/p2p.c
index 2b90da0d85f3..e7a1a4770996 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/p2p.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/p2p.c
@@ -1117,7 +1117,7 @@ static void brcmf_p2p_afx_handler(struct work_struct *work)
 	if (afx_hdl->is_listen && afx_hdl->my_listen_chan)
 		/* 100ms ~ 300ms */
 		err = brcmf_p2p_discover_listen(p2p, afx_hdl->my_listen_chan,
-						100 * (1 + (random32() % 3)));
+						100 * (1 + prandom_u32() % 3));
 	else
 		err = brcmf_p2p_act_frm_search(p2p, afx_hdl->peer_listen_chan);
 
diff --git a/drivers/net/wireless/mwifiex/cfg80211.c b/drivers/net/wireless/mwifiex/cfg80211.c
index a0cb0770d319..d3c8ece980d8 100644
--- a/drivers/net/wireless/mwifiex/cfg80211.c
+++ b/drivers/net/wireless/mwifiex/cfg80211.c
@@ -216,7 +216,7 @@ mwifiex_cfg80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
 	mwifiex_form_mgmt_frame(skb, buf, len);
 	mwifiex_queue_tx_pkt(priv, skb);
 
-	*cookie = random32() | 1;
+	*cookie = prandom_u32() | 1;
 	cfg80211_mgmt_tx_status(wdev, *cookie, buf, len, true, GFP_ATOMIC);
 
 	wiphy_dbg(wiphy, "info: management frame transmitted\n");
@@ -271,7 +271,7 @@ mwifiex_cfg80211_remain_on_channel(struct wiphy *wiphy,
 					 duration);
 
 	if (!ret) {
-		*cookie = random32() | 1;
+		*cookie = prandom_u32() | 1;
 		priv->roc_cfg.cookie = *cookie;
 		priv->roc_cfg.chan = *chan;
 
diff --git a/drivers/rtc/rtc-rs5c372.c b/drivers/rtc/rtc-rs5c372.c
index 224d634322b4..ccf54f06396b 100644
--- a/drivers/rtc/rtc-rs5c372.c
+++ b/drivers/rtc/rtc-rs5c372.c
@@ -68,6 +68,7 @@
 enum rtc_type {
 	rtc_undef = 0,
 	rtc_r2025sd,
+	rtc_r2221tl,
 	rtc_rs5c372a,
 	rtc_rs5c372b,
 	rtc_rv5c386,
@@ -76,6 +77,7 @@ enum rtc_type {
 
 static const struct i2c_device_id rs5c372_id[] = {
 	{ "r2025sd", rtc_r2025sd },
+	{ "r2221tl", rtc_r2221tl },
 	{ "rs5c372a", rtc_rs5c372a },
 	{ "rs5c372b", rtc_rs5c372b },
 	{ "rv5c386", rtc_rv5c386 },
@@ -529,6 +531,7 @@ static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
 		rs5c372->time24 = 1;
 		break;
 	case rtc_r2025sd:
+	case rtc_r2221tl:
 	case rtc_rv5c386:
 	case rtc_rv5c387a:
 		buf[0] |= RV5C387_CTRL1_24;
@@ -609,6 +612,7 @@ static int rs5c372_probe(struct i2c_client *client,
 			rs5c372->time24 = 1;
 		break;
 	case rtc_r2025sd:
+	case rtc_r2221tl:
 	case rtc_rv5c386:
 	case rtc_rv5c387a:
 		if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
@@ -640,6 +644,7 @@ static int rs5c372_probe(struct i2c_client *client,
 	dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
 			({ char *s; switch (rs5c372->type) {
 			case rtc_r2025sd:	s = "r2025sd"; break;
+			case rtc_r2221tl:	s = "r2221tl"; break;
 			case rtc_rs5c372a:	s = "rs5c372a"; break;
 			case rtc_rs5c372b:	s = "rs5c372b"; break;
 			case rtc_rv5c386:	s = "rv5c386"; break;
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 9f0c46547459..df5e961484e1 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -35,6 +35,7 @@ static int sg_version_num = 30534;	/* 2 digits for each component */
 #include <linux/sched.h>
 #include <linux/string.h>
 #include <linux/mm.h>
+#include <linux/aio.h>
 #include <linux/errno.h>
 #include <linux/mtio.h>
 #include <linux/ioctl.h>
diff --git a/drivers/staging/android/logger.c b/drivers/staging/android/logger.c
index b14a55742559..b040200a5a55 100644
--- a/drivers/staging/android/logger.c
+++ b/drivers/staging/android/logger.c
@@ -28,6 +28,7 @@
 #include <linux/slab.h>
 #include <linux/time.h>
 #include <linux/vmalloc.h>
+#include <linux/aio.h>
 #include "logger.h"
 
 #include <asm/ioctls.h>
diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c
index dda0dc4a5567..570c005062ab 100644
--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -24,6 +24,8 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/poll.h>
+#include <linux/mmu_context.h>
+#include <linux/aio.h>
 
 #include <linux/device.h>
 #include <linux/moduleparam.h>
@@ -513,6 +515,9 @@ static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
 struct kiocb_priv {
 	struct usb_request	*req;
 	struct ep_data		*epdata;
+	struct kiocb		*iocb;
+	struct mm_struct	*mm;
+	struct work_struct	work;
 	void			*buf;
 	const struct iovec	*iv;
 	unsigned long		nr_segs;
@@ -528,7 +533,6 @@ static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
 	local_irq_disable();
 	epdata = priv->epdata;
 	// spin_lock(&epdata->dev->lock);
-	kiocbSetCancelled(iocb);
 	if (likely(epdata && epdata->ep && priv->req))
 		value = usb_ep_dequeue (epdata->ep, priv->req);
 	else
@@ -540,15 +544,12 @@ static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
 	return value;
 }
 
-static ssize_t ep_aio_read_retry(struct kiocb *iocb)
+static ssize_t ep_copy_to_user(struct kiocb_priv *priv)
 {
-	struct kiocb_priv	*priv = iocb->private;
 	ssize_t			len, total;
 	void			*to_copy;
 	int			i;
 
-	/* we "retry" to get the right mm context for this: */
-
 	/* copy stuff into user buffers */
 	total = priv->actual;
 	len = 0;
@@ -568,9 +569,26 @@ static ssize_t ep_aio_read_retry(struct kiocb *iocb)
 		if (total == 0)
 			break;
 	}
+
+	return len;
+}
+
+static void ep_user_copy_worker(struct work_struct *work)
+{
+	struct kiocb_priv *priv = container_of(work, struct kiocb_priv, work);
+	struct mm_struct *mm = priv->mm;
+	struct kiocb *iocb = priv->iocb;
+	size_t ret;
+
+	use_mm(mm);
+	ret = ep_copy_to_user(priv);
+	unuse_mm(mm);
+
+	/* completing the iocb can drop the ctx and mm, don't touch mm after */
+	aio_complete(iocb, ret, ret);
+
 	kfree(priv->buf);
 	kfree(priv);
-	return len;
 }
 
 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
@@ -596,14 +614,14 @@ static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
 		aio_complete(iocb, req->actual ? req->actual : req->status,
 				req->status);
 	} else {
-		/* retry() won't report both; so we hide some faults */
+		/* ep_copy_to_user() won't report both; we hide some faults */
 		if (unlikely(0 != req->status))
 			DBG(epdata->dev, "%s fault %d len %d\n",
 				ep->name, req->status, req->actual);
 
 		priv->buf = req->buf;
 		priv->actual = req->actual;
-		kick_iocb(iocb);
+		schedule_work(&priv->work);
 	}
 	spin_unlock(&epdata->dev->lock);
 
@@ -633,8 +651,10 @@ fail:
 		return value;
 	}
 	iocb->private = priv;
+	priv->iocb = iocb;
 	priv->iv = iv;
 	priv->nr_segs = nr_segs;
+	INIT_WORK(&priv->work, ep_user_copy_worker);
 
 	value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
 	if (unlikely(value < 0)) {
@@ -642,10 +662,11 @@ fail:
 		goto fail;
 	}
 
-	iocb->ki_cancel = ep_aio_cancel;
+	kiocb_set_cancel_fn(iocb, ep_aio_cancel);
 	get_ep(epdata);
 	priv->epdata = epdata;
 	priv->actual = 0;
+	priv->mm = current->mm; /* mm teardown waits for iocbs in exit_aio() */
 
 	/* each kiocb is coupled to one usb_request, but we can't
 	 * allocate or submit those if the host disconnected.
@@ -674,7 +695,7 @@ fail:
 		kfree(priv);
 		put_ep(epdata);
 	} else
-		value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
+		value = -EIOCBQUEUED;
 	return value;
 }
 
@@ -692,7 +713,6 @@ ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
 	if (unlikely(!buf))
 		return -ENOMEM;
 
-	iocb->ki_retry = ep_aio_read_retry;
 	return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
 }