C++ EXPORT_SYMBOL_GPL函数代码示例

int hns_roce_alloc_pd(struct ib_pd *ibpd, struct ib_ucontext *context,
		      struct ib_udata *udata)
{
	struct ib_device *ib_dev = ibpd->device;
	struct hns_roce_dev *hr_dev = to_hr_dev(ib_dev);
	struct device *dev = hr_dev->dev;
	struct hns_roce_pd *pd = to_hr_pd(ibpd);
	int ret;

	ret = hns_roce_pd_alloc(to_hr_dev(ib_dev), &pd->pdn);
	if (ret) {
		dev_err(dev, "[alloc_pd]hns_roce_pd_alloc failed!\n");
		return ret;
	}

	if (context) {
		struct hns_roce_ib_alloc_pd_resp uresp = {.pdn = pd->pdn};

		if (ib_copy_to_udata(udata, &uresp, sizeof(uresp))) {
			hns_roce_pd_free(to_hr_dev(ib_dev), pd->pdn);
			dev_err(dev, "[alloc_pd]ib_copy_to_udata failed!\n");
			return -EFAULT;
		}
	}

	return 0;
}
EXPORT_SYMBOL_GPL(hns_roce_alloc_pd);

void hns_roce_dealloc_pd(struct ib_pd *pd)
{
	hns_roce_pd_free(to_hr_dev(pd->device), to_hr_pd(pd)->pdn);
}

/*
 * Set up a pNFS Data Server client over NFSv3.
 *
 * Return any existing nfs_client that matches server address,port,version
 * and minorversion.
 *
 * For a new nfs_client, use a soft mount (default), a low retrans and a
 * low timeout interval so that if a connection is lost, we retry through
 * the MDS.
 */
struct nfs_client *nfs3_set_ds_client(struct nfs_server *mds_srv,
		const struct sockaddr *ds_addr, int ds_addrlen,
		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans)
{
	struct rpc_timeout ds_timeout;
	struct nfs_client *mds_clp = mds_srv->nfs_client;
	struct nfs_client_initdata cl_init = {
		.addr = ds_addr,
		.addrlen = ds_addrlen,
		.nodename = mds_clp->cl_rpcclient->cl_nodename,
		.ip_addr = mds_clp->cl_ipaddr,
		.nfs_mod = &nfs_v3,
		.proto = ds_proto,
		.net = mds_clp->cl_net,
		.timeparms = &ds_timeout,
		.cred = mds_srv->cred,
	};
	struct nfs_client *clp;
	char buf[INET6_ADDRSTRLEN + 1];

	/* fake a hostname because lockd wants it */
	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
		return ERR_PTR(-EINVAL);
	cl_init.hostname = buf;

	if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);

	/* Use the MDS nfs_client cl_ipaddr. */
	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
	clp = nfs_get_client(&cl_init);

	return clp;
}
EXPORT_SYMBOL_GPL(nfs3_set_ds_client);

void gcore_input_report_key(struct gcore_data *gdata, int scancode, int value)
{
	struct input_dev *idev = gdata->input_dev;
	int error;

	struct input_keymap_entry ke = {
		.flags	  = 0,
		.len	  = sizeof(scancode),
	};
	*((int *) ke.scancode) = scancode;

	error = input_get_keycode(idev, &ke);
	if (!error && ke.keycode != KEY_UNKNOWN && ke.keycode != KEY_RESERVED) {
		/* Only report mapped keys */
		input_report_key(idev, ke.keycode, value);
	} else if (!!value) {
		/* Or report MSC_SCAN on keypress of an unmapped key */
		input_event(idev, EV_MSC, MSC_SCAN, scancode);
	}
}
EXPORT_SYMBOL_GPL(gcore_input_report_key);


void gcore_input_remove(struct gcore_data *gdata)
{
	input_unregister_device(gdata->input_dev);
	kfree(gdata->input_dev->keycode);
}

/**
 * dax_zero_page_range - zero a range within a page of a DAX file
 * @inode: The file being truncated
 * @from: The file offset that is being truncated to
 * @length: The number of bytes to zero
 * @get_block: The filesystem method used to translate file offsets to blocks
 *
 * This function can be called by a filesystem when it is zeroing part of a
 * page in a DAX file.  This is intended for hole-punch operations.  If
 * you are truncating a file, the helper function dax_truncate_page() may be
 * more convenient.
 *
 * We work in terms of PAGE_SIZE here for commonality with
 * block_truncate_page(), but we could go down to PAGE_SIZE if the filesystem
 * took care of disposing of the unnecessary blocks.  Even if the filesystem
 * block size is smaller than PAGE_SIZE, we have to zero the rest of the page
 * since the file might be mmapped.
 */
int dax_zero_page_range(struct inode *inode, loff_t from, unsigned length,
							get_block_t get_block)
{
	struct buffer_head bh;
	pgoff_t index = from >> PAGE_SHIFT;
	unsigned offset = from & (PAGE_SIZE-1);
	int err;

	/* Block boundary? Nothing to do */
	if (!length)
		return 0;
	BUG_ON((offset + length) > PAGE_SIZE);

	memset(&bh, 0, sizeof(bh));
	bh.b_bdev = inode->i_sb->s_bdev;
	bh.b_size = PAGE_SIZE;
	err = get_block(inode, index, &bh, 0);
	if (err < 0)
		return err;
	if (buffer_written(&bh)) {
		struct block_device *bdev = bh.b_bdev;
		struct blk_dax_ctl dax = {
			.sector = to_sector(&bh, inode),
			.size = PAGE_SIZE,
		};

		if (dax_map_atomic(bdev, &dax) < 0)
			return PTR_ERR(dax.addr);
		clear_pmem(dax.addr + offset, length);
		wmb_pmem();
		dax_unmap_atomic(bdev, &dax);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(dax_zero_page_range);

/**
 * dax_truncate_page - handle a partial page being truncated in a DAX file
 * @inode: The file being truncated
 * @from: The file offset that is being truncated to
 * @get_block: The filesystem method used to translate file offsets to blocks
 *
 * Similar to block_truncate_page(), this function can be called by a
 * filesystem when it is truncating a DAX file to handle the partial page.
 *
 * We work in terms of PAGE_SIZE here for commonality with
 * block_truncate_page(), but we could go down to PAGE_SIZE if the filesystem
 * took care of disposing of the unnecessary blocks.  Even if the filesystem
 * block size is smaller than PAGE_SIZE, we have to zero the rest of the page
 * since the file might be mmapped.
 */
int dax_truncate_page(struct inode *inode, loff_t from, get_block_t get_block)
{
	unsigned length = PAGE_ALIGN(from) - from;
	return dax_zero_page_range(inode, from, length, get_block);
}

/**
 * ad_sd_write_reg() - Write a register
 *
 * @sigma_delta: The sigma delta device
 * @reg: Address of the register
 * @size: Size of the register (0-3)
 * @val: Value to write to the register
 *
 * Returns 0 on success, an error code otherwise.
 **/
int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg,
	unsigned int size, unsigned int val)
{
	uint8_t *data = sigma_delta->data;
	struct spi_transfer t = {
		.tx_buf		= data,
		.len		= size + 1,
		.cs_change	= sigma_delta->bus_locked,
	};
	struct spi_message m;
	int ret;

	data[0] = (reg << sigma_delta->info->addr_shift) | sigma_delta->comm;

	switch (size) {
	case 3:
		data[1] = val >> 16;
		data[2] = val >> 8;
		data[3] = val;
		break;
	case 2:
		put_unaligned_be16(val, &data[1]);
		break;
	case 1:
		data[1] = val;
		break;
	case 0:
		break;
	default:
		return -EINVAL;
	}

	spi_message_init(&m);
	spi_message_add_tail(&t, &m);

	if (sigma_delta->bus_locked)
		ret = spi_sync_locked(sigma_delta->spi, &m);
	else
		ret = spi_sync(sigma_delta->spi, &m);

	return ret;
}
EXPORT_SYMBOL_GPL(ad_sd_write_reg);

static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta,
	unsigned int reg, unsigned int size, uint8_t *val)
{
	uint8_t *data = sigma_delta->data;
	int ret;
	struct spi_transfer t[] = {
		{
			.tx_buf = data,
			.len = 1,
		}, {
			.rx_buf = val,

int rave_sp_exec(struct rave_sp *sp,
		 void *__data,  size_t data_size,
		 void *reply_data, size_t reply_data_size)
{
	struct rave_sp_reply reply = {
		.data     = reply_data,
		.length   = reply_data_size,
		.received = COMPLETION_INITIALIZER_ONSTACK(reply.received),
	};
	unsigned char *data = __data;
	int command, ret = 0;
	u8 ackid;

	command = sp->variant->cmd.translate(data[0]);
	if (command < 0)
		return command;

	ackid       = atomic_inc_return(&sp->ackid);
	reply.ackid = ackid;
	reply.code  = rave_sp_reply_code((u8)command),

	mutex_lock(&sp->bus_lock);

	mutex_lock(&sp->reply_lock);
	sp->reply = &reply;
	mutex_unlock(&sp->reply_lock);

	data[0] = command;
	data[1] = ackid;

	rave_sp_write(sp, data, data_size);

	if (!wait_for_completion_timeout(&reply.received, HZ)) {
		dev_err(&sp->serdev->dev, "Command timeout\n");
		ret = -ETIMEDOUT;

		mutex_lock(&sp->reply_lock);
		sp->reply = NULL;
		mutex_unlock(&sp->reply_lock);
	}

	mutex_unlock(&sp->bus_lock);
	return ret;
}
EXPORT_SYMBOL_GPL(rave_sp_exec);

static void rave_sp_receive_event(struct rave_sp *sp,
				  const unsigned char *data, size_t length)
{
	u8 cmd[] = {
		[0] = rave_sp_reply_code(data[0]),
		[1] = data[1],
	};

void save_stack_trace_tsk(struct task_struct *task, struct stack_trace *trace)
{
	struct stack_trace_data trace_data = {
		.trace = trace,
		.skip = trace->skip,
	};
	walk_stackframe(stack_pointer(task), stack_trace_cb, &trace_data);
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);

void save_stack_trace(struct stack_trace *trace)
{
	save_stack_trace_tsk(current, trace);
}

/**
 * nfs_do_submount - set up mountpoint when crossing a filesystem boundary
 * @dentry - parent directory
 * @fh - filehandle for new root dentry
 * @fattr - attributes for new root inode
 * @authflavor - security flavor to use when performing the mount
 *
 */
struct vfsmount *nfs_do_submount(struct dentry *dentry, struct nfs_fh *fh,
				 struct nfs_fattr *fattr, rpc_authflavor_t authflavor)
{
	struct nfs_clone_mount mountdata = {
		.sb = dentry->d_sb,
		.dentry = dentry,
		.fh = fh,
		.fattr = fattr,
		.authflavor = authflavor,
	};
	struct vfsmount *mnt = ERR_PTR(-ENOMEM);
	char *page = (char *) __get_free_page(GFP_USER);
	char *devname;

	dprintk("--> nfs_do_submount()\n");

	dprintk("%s: submounting on %s/%s\n", __func__,
			dentry->d_parent->d_name.name,
			dentry->d_name.name);
	if (page == NULL)
		goto out;
	devname = nfs_devname(dentry, page, PAGE_SIZE);
	mnt = (struct vfsmount *)devname;
	if (IS_ERR(devname))
		goto free_page;
	mnt = nfs_do_clone_mount(NFS_SB(dentry->d_sb), devname, &mountdata);
free_page:
	free_page((unsigned long)page);
out:
	dprintk("%s: done\n", __func__);

	dprintk("<-- nfs_do_submount() = %p\n", mnt);
	return mnt;
}
EXPORT_SYMBOL_GPL(nfs_do_submount);

struct vfsmount *nfs_submount(struct nfs_server *server, struct dentry *dentry,
			      struct nfs_fh *fh, struct nfs_fattr *fattr)
{
	int err;
	struct dentry *parent = dget_parent(dentry);

	/* Look it up again to get its attributes */
	err = server->nfs_client->rpc_ops->lookup(parent->d_inode, &dentry->d_name, fh, fattr);
	dput(parent);
	if (err != 0)
		return ERR_PTR(err);

	return nfs_do_submount(dentry, fh, fattr, server->client->cl_auth->au_flavor);
}

int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, u32 id,
		       u32 ts, u32 tsage, long expires, u32 error)
{
	struct rta_cacheinfo ci = {
		.rta_lastuse = jiffies_to_clock_t(jiffies - dst->lastuse),
		.rta_used = dst->__use,
		.rta_clntref = atomic_read(&(dst->__refcnt)),
		.rta_error = error,
		.rta_id =  id,
		.rta_ts = ts,
		.rta_tsage = tsage,
	};

	if (expires)
		ci.rta_expires = jiffies_to_clock_t(expires);

	return nla_put(skb, RTA_CACHEINFO, sizeof(ci), &ci);
}

EXPORT_SYMBOL_GPL(rtnl_put_cacheinfo);

static void set_operstate(struct net_device *dev, unsigned char transition)
{
	unsigned char operstate = dev->operstate;

	switch(transition) {
	case IF_OPER_UP:
		if ((operstate == IF_OPER_DORMANT ||
		     operstate == IF_OPER_UNKNOWN) &&
		    !netif_dormant(dev))
			operstate = IF_OPER_UP;
		break;

	case IF_OPER_DORMANT:
		if (operstate == IF_OPER_UP ||
		    operstate == IF_OPER_UNKNOWN)
			operstate = IF_OPER_DORMANT;
		break;
	}

	if (dev->operstate != operstate) {
		write_lock_bh(&dev_base_lock);
		dev->operstate = operstate;
		write_unlock_bh(&dev_base_lock);
		netdev_state_change(dev);
	}
}

static int pmf_get_detect(struct gpio_runtime *rt,
			  enum notify_type type)
{
	char *name;
	int err = -EBUSY, ret;
	struct pmf_args args = { .count = 1, .u[0].p = &ret };

	switch (type) {
	case AOA_NOTIFY_HEADPHONE:
		name = "headphone-detect";
		break;
	case AOA_NOTIFY_LINE_IN:
		name = "linein-detect";
		break;
	case AOA_NOTIFY_LINE_OUT:
		name = "lineout-detect";
		break;
	default:
		return -EINVAL;
	}

	err = pmf_call_function(rt->node, name, &args);
	if (err)
		return err;
	return ret;
}

static struct gpio_methods methods = {
	.init			= pmf_gpio_init,
	.exit			= pmf_gpio_exit,
	.all_amps_off		= pmf_gpio_all_amps_off,
	.all_amps_restore	= pmf_gpio_all_amps_restore,
	.set_headphone		= pmf_gpio_set_headphone,
	.set_speakers		= pmf_gpio_set_amp,
	.set_lineout		= pmf_gpio_set_lineout,
	.set_hw_reset		= pmf_gpio_set_hw_reset,
	.get_headphone		= pmf_gpio_get_headphone,
	.get_speakers		= pmf_gpio_get_amp,
	.get_lineout		= pmf_gpio_get_lineout,
	.set_notify		= pmf_set_notify,
	.get_detect		= pmf_get_detect,
};

struct gpio_methods *pmf_gpio_methods = &methods;
EXPORT_SYMBOL_GPL(pmf_gpio_methods);

/* Extract info for Tcp socket info provided via netlink. */
void tcp_vegas_get_info(struct sock *sk, u32 ext, struct sk_buff *skb)
{
	const struct vegas *ca = inet_csk_ca(sk);
	if (ext & (1 << (INET_DIAG_VEGASINFO - 1))) {
		struct tcpvegas_info info = {
			.tcpv_enabled = ca->doing_vegas_now,
			.tcpv_rttcnt = ca->cntRTT,
			.tcpv_rtt = ca->baseRTT,
			.tcpv_minrtt = ca->minRTT,
		};

		nla_put(skb, INET_DIAG_VEGASINFO, sizeof(info), &info);
	}
}
EXPORT_SYMBOL_GPL(tcp_vegas_get_info);

static struct tcp_congestion_ops tcp_vegas __read_mostly = {
	.flags		= TCP_CONG_RTT_STAMP,
	.init		= tcp_vegas_init,
	.ssthresh	= tcp_reno_ssthresh,
	.cong_avoid	= tcp_vegas_cong_avoid,
	.min_cwnd	= tcp_reno_min_cwnd,
	.pkts_acked	= tcp_vegas_pkts_acked,
	.set_state	= tcp_vegas_state,
	.cwnd_event	= tcp_vegas_cwnd_event,
	.get_info	= tcp_vegas_get_info,

	.owner		= THIS_MODULE,
	.name		= "vegas",
};

static int __init tcp_vegas_register(void)
{
	BUILD_BUG_ON(sizeof(struct vegas) > ICSK_CA_PRIV_SIZE);
	tcp_register_congestion_control(&tcp_vegas);
	return 0;
}

static void __exit tcp_vegas_unregister(void)
{
	tcp_unregister_congestion_control(&tcp_vegas);
}

/**
 * nfs_do_submount - set up mountpoint when crossing a filesystem boundary
 * @dentry - parent directory
 * @fh - filehandle for new root dentry
 * @fattr - attributes for new root inode
 * @authflavor - security flavor to use when performing the mount
 *
 */
struct vfsmount *nfs_do_submount(struct dentry *dentry, struct nfs_fh *fh,
				 struct nfs_fattr *fattr, rpc_authflavor_t authflavor)
{
	struct nfs_clone_mount mountdata = {
		.sb = dentry->d_sb,
		.dentry = dentry,
		.fh = fh,
		.fattr = fattr,
		.authflavor = authflavor,
	};
	struct vfsmount *mnt;
	char *page = (char *) __get_free_page(GFP_USER);
	char *devname;

	if (page == NULL)
		return ERR_PTR(-ENOMEM);

	devname = nfs_devname(dentry, page, PAGE_SIZE);
	if (IS_ERR(devname))
		mnt = (struct vfsmount *)devname;
	else
		mnt = nfs_do_clone_mount(NFS_SB(dentry->d_sb), devname, &mountdata);

	free_page((unsigned long)page);
	return mnt;
}
EXPORT_SYMBOL_GPL(nfs_do_submount);

struct vfsmount *nfs_submount(struct nfs_server *server, struct dentry *dentry,
			      struct nfs_fh *fh, struct nfs_fattr *fattr)
{
	int err;
	struct dentry *parent = dget_parent(dentry);

	/* Look it up again to get its attributes */
	err = server->nfs_client->rpc_ops->lookup(d_inode(parent), &dentry->d_name, fh, fattr, NULL);
	dput(parent);
	if (err != 0)
		return ERR_PTR(err);

	return nfs_do_submount(dentry, fh, fattr, server->client->cl_auth->au_flavor);
}

void xen_free_vm_area(struct vm_struct *area)
{
	unsigned int order = get_order(area->size);
	unsigned long i;
	unsigned long phys_addr = __pa(area->addr);

	/* This area is used for foreign page mappping.
	 * So underlying machine page may not be assigned. */
	for (i = 0; i < (1 << order); i++) {
		unsigned long ret;
		unsigned long gpfn = (phys_addr >> PAGE_SHIFT) + i;
		struct xen_memory_reservation reservation = {
			.nr_extents   = 1,
			.address_bits = 0,
			.extent_order = 0,
			.domid        = DOMID_SELF
		};
		set_xen_guest_handle(reservation.extent_start, &gpfn);
		ret = HYPERVISOR_memory_op(XENMEM_populate_physmap,
					   &reservation);
		BUG_ON(ret != 1);
	}
	free_pages((unsigned long)area->addr, order);
	kfree(area);
}
EXPORT_SYMBOL_GPL(xen_free_vm_area);


/****************************************************************************
 * grant table hack
 * cmd: GNTTABOP_xxx
 */

int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
			   unsigned long max_nr_gframes,
			   struct grant_entry **__shared)
{
	*__shared = __va(frames[0] << PAGE_SHIFT);
	return 0;
}

void mars_digest(unsigned char *digest, void *data, int len)
{
	struct hash_desc desc = {
		.tfm = mars_tfm,
		.flags = 0,
	};
	struct scatterlist sg;

	memset(digest, 0, mars_digest_size);

	// TODO: use per-thread instance, omit locking
	down(&tfm_sem);

	crypto_hash_init(&desc);
	sg_init_table(&sg, 1);
	sg_set_buf(&sg, data, len);
	crypto_hash_update(&desc, &sg, sg.length);
	crypto_hash_final(&desc, digest);
	up(&tfm_sem);
}
EXPORT_SYMBOL_GPL(mars_digest);

void mref_checksum(struct mref_object *mref)
{
	unsigned char checksum[mars_digest_size];
	int len;

	if (mref->ref_cs_mode <= 0 || !mref->ref_data)
		return;

	mars_digest(checksum, mref->ref_data, mref->ref_len);

	len = sizeof(mref->ref_checksum);
	if (len > mars_digest_size)
		len = mars_digest_size;
	memcpy(&mref->ref_checksum, checksum, len);
}

/**
 * stack_trace_save - Save a stack trace into a storage array
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored
 */
unsigned int stack_trace_save(unsigned long *store, unsigned int size,
			      unsigned int skipnr)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
		.skip		= skipnr + 1,
	};

	save_stack_trace(&trace);
	return trace.nr_entries;
}
EXPORT_SYMBOL_GPL(stack_trace_save);

/**
 * stack_trace_save_tsk - Save a task stack trace into a storage array
 * @task:	The task to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored
 */
unsigned int stack_trace_save_tsk(struct task_struct *task,
				  unsigned long *store, unsigned int size,
				  unsigned int skipnr)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
		.skip		= skipnr + 1,
	};

	save_stack_trace_tsk(task, &trace);
	return trace.nr_entries;
}

/**
 * stack_trace_save_regs - Save a stack trace based on pt_regs into a storage array
 * @regs:	Pointer to pt_regs to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 * @skipnr:	Number of entries to skip at the start of the stack trace
 *
 * Return: Number of trace entries stored
 */
unsigned int stack_trace_save_regs(struct pt_regs *regs, unsigned long *store,
				   unsigned int size, unsigned int skipnr)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
		.skip		= skipnr,
	};

	save_stack_trace_regs(regs, &trace);
	return trace.nr_entries;
}

#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE
/**
 * stack_trace_save_tsk_reliable - Save task stack with verification
 * @tsk:	Pointer to the task to examine
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 *
 * Return:	An error if it detects any unreliable features of the
 *		stack. Otherwise it guarantees that the stack trace is
 *		reliable and returns the number of entries stored.
 *
 * If the task is not 'current', the caller *must* ensure the task is inactive.
 */
int stack_trace_save_tsk_reliable(struct task_struct *tsk, unsigned long *store,
				  unsigned int size)
{
	struct stack_trace trace = {
		.entries	= store,
		.max_entries	= size,
	};
	int ret = save_stack_trace_tsk_reliable(tsk, &trace);

	return ret ? ret : trace.nr_entries;
}
#endif

#ifdef CONFIG_USER_STACKTRACE_SUPPORT
/**
 * stack_trace_save_user - Save a user space stack trace into a storage array
 * @store:	Pointer to storage array
 * @size:	Size of the storage array
 *
 * Return: Number of trace entries stored
//.........这里部分代码省略.........