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-rw-r--r--arch/powerpc/platforms/pseries/hvcserver.c239
1 files changed, 239 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/hvcserver.c b/arch/powerpc/platforms/pseries/hvcserver.c
new file mode 100644
index 000000000..96e18d3b2
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/hvcserver.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * hvcserver.c
+ * Copyright (C) 2004 Ryan S Arnold, IBM Corporation
+ *
+ * PPC64 virtual I/O console server support.
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include <asm/hvcall.h>
+#include <asm/hvcserver.h>
+#include <asm/io.h>
+
+#define HVCS_ARCH_VERSION "1.0.0"
+
+MODULE_AUTHOR("Ryan S. Arnold <rsa@us.ibm.com>");
+MODULE_DESCRIPTION("IBM hvcs ppc64 API");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(HVCS_ARCH_VERSION);
+
+/*
+ * Convert arch specific return codes into relevant errnos. The hvcs
+ * functions aren't performance sensitive, so this conversion isn't an
+ * issue.
+ */
+static int hvcs_convert(long to_convert)
+{
+ switch (to_convert) {
+ case H_SUCCESS:
+ return 0;
+ case H_PARAMETER:
+ return -EINVAL;
+ case H_HARDWARE:
+ return -EIO;
+ case H_BUSY:
+ case H_LONG_BUSY_ORDER_1_MSEC:
+ case H_LONG_BUSY_ORDER_10_MSEC:
+ case H_LONG_BUSY_ORDER_100_MSEC:
+ case H_LONG_BUSY_ORDER_1_SEC:
+ case H_LONG_BUSY_ORDER_10_SEC:
+ case H_LONG_BUSY_ORDER_100_SEC:
+ return -EBUSY;
+ case H_FUNCTION:
+ default:
+ return -EPERM;
+ }
+}
+
+/**
+ * hvcs_free_partner_info - free pi allocated by hvcs_get_partner_info
+ * @head: list_head pointer for an allocated list of partner info structs to
+ * free.
+ *
+ * This function is used to free the partner info list that was returned by
+ * calling hvcs_get_partner_info().
+ */
+int hvcs_free_partner_info(struct list_head *head)
+{
+ struct hvcs_partner_info *pi;
+ struct list_head *element;
+
+ if (!head)
+ return -EINVAL;
+
+ while (!list_empty(head)) {
+ element = head->next;
+ pi = list_entry(element, struct hvcs_partner_info, node);
+ list_del(element);
+ kfree(pi);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(hvcs_free_partner_info);
+
+/* Helper function for hvcs_get_partner_info */
+static int hvcs_next_partner(uint32_t unit_address,
+ unsigned long last_p_partition_ID,
+ unsigned long last_p_unit_address, unsigned long *pi_buff)
+
+{
+ long retval;
+ retval = plpar_hcall_norets(H_VTERM_PARTNER_INFO, unit_address,
+ last_p_partition_ID,
+ last_p_unit_address, virt_to_phys(pi_buff));
+ return hvcs_convert(retval);
+}
+
+/**
+ * hvcs_get_partner_info - Get all of the partner info for a vty-server adapter
+ * @unit_address: The unit_address of the vty-server adapter for which this
+ * function is fetching partner info.
+ * @head: An initialized list_head pointer to an empty list to use to return the
+ * list of partner info fetched from the hypervisor to the caller.
+ * @pi_buff: A page sized buffer pre-allocated prior to calling this function
+ * that is to be used to be used by firmware as an iterator to keep track
+ * of the partner info retrieval.
+ *
+ * This function returns non-zero on success, or if there is no partner info.
+ *
+ * The pi_buff is pre-allocated prior to calling this function because this
+ * function may be called with a spin_lock held and kmalloc of a page is not
+ * recommended as GFP_ATOMIC.
+ *
+ * The first long of this buffer is used to store a partner unit address. The
+ * second long is used to store a partner partition ID and starting at
+ * pi_buff[2] is the 79 character Converged Location Code (diff size than the
+ * unsigned longs, hence the casting mumbo jumbo you see later).
+ *
+ * Invocation of this function should always be followed by an invocation of
+ * hvcs_free_partner_info() using a pointer to the SAME list head instance
+ * that was passed as a parameter to this function.
+ */
+int hvcs_get_partner_info(uint32_t unit_address, struct list_head *head,
+ unsigned long *pi_buff)
+{
+ /*
+ * Dealt with as longs because of the hcall interface even though the
+ * values are uint32_t.
+ */
+ unsigned long last_p_partition_ID;
+ unsigned long last_p_unit_address;
+ struct hvcs_partner_info *next_partner_info = NULL;
+ int more = 1;
+ int retval;
+
+ /* invalid parameters */
+ if (!head || !pi_buff)
+ return -EINVAL;
+
+ memset(pi_buff, 0x00, PAGE_SIZE);
+ last_p_partition_ID = last_p_unit_address = ~0UL;
+ INIT_LIST_HEAD(head);
+
+ do {
+ retval = hvcs_next_partner(unit_address, last_p_partition_ID,
+ last_p_unit_address, pi_buff);
+ if (retval) {
+ /*
+ * Don't indicate that we've failed if we have
+ * any list elements.
+ */
+ if (!list_empty(head))
+ return 0;
+ return retval;
+ }
+
+ last_p_partition_ID = be64_to_cpu(pi_buff[0]);
+ last_p_unit_address = be64_to_cpu(pi_buff[1]);
+
+ /* This indicates that there are no further partners */
+ if (last_p_partition_ID == ~0UL
+ && last_p_unit_address == ~0UL)
+ break;
+
+ /* This is a very small struct and will be freed soon in
+ * hvcs_free_partner_info(). */
+ next_partner_info = kmalloc(sizeof(struct hvcs_partner_info),
+ GFP_ATOMIC);
+
+ if (!next_partner_info) {
+ printk(KERN_WARNING "HVCONSOLE: kmalloc() failed to"
+ " allocate partner info struct.\n");
+ hvcs_free_partner_info(head);
+ return -ENOMEM;
+ }
+
+ next_partner_info->unit_address
+ = (unsigned int)last_p_unit_address;
+ next_partner_info->partition_ID
+ = (unsigned int)last_p_partition_ID;
+
+ /* copy the Null-term char too */
+ strlcpy(&next_partner_info->location_code[0],
+ (char *)&pi_buff[2],
+ sizeof(next_partner_info->location_code));
+
+ list_add_tail(&(next_partner_info->node), head);
+ next_partner_info = NULL;
+
+ } while (more);
+
+ return 0;
+}
+EXPORT_SYMBOL(hvcs_get_partner_info);
+
+/**
+ * hvcs_register_connection - establish a connection between this vty-server and
+ * a vty.
+ * @unit_address: The unit address of the vty-server adapter that is to be
+ * establish a connection.
+ * @p_partition_ID: The partition ID of the vty adapter that is to be connected.
+ * @p_unit_address: The unit address of the vty adapter to which the vty-server
+ * is to be connected.
+ *
+ * If this function is called once and -EINVAL is returned it may
+ * indicate that the partner info needs to be refreshed for the
+ * target unit address at which point the caller must invoke
+ * hvcs_get_partner_info() and then call this function again. If,
+ * for a second time, -EINVAL is returned then it indicates that
+ * there is probably already a partner connection registered to a
+ * different vty-server adapter. It is also possible that a second
+ * -EINVAL may indicate that one of the parms is not valid, for
+ * instance if the link was removed between the vty-server adapter
+ * and the vty adapter that you are trying to open. Don't shoot the
+ * messenger. Firmware implemented it this way.
+ */
+int hvcs_register_connection( uint32_t unit_address,
+ uint32_t p_partition_ID, uint32_t p_unit_address)
+{
+ long retval;
+ retval = plpar_hcall_norets(H_REGISTER_VTERM, unit_address,
+ p_partition_ID, p_unit_address);
+ return hvcs_convert(retval);
+}
+EXPORT_SYMBOL(hvcs_register_connection);
+
+/**
+ * hvcs_free_connection - free the connection between a vty-server and vty
+ * @unit_address: The unit address of the vty-server that is to have its
+ * connection severed.
+ *
+ * This function is used to free the partner connection between a vty-server
+ * adapter and a vty adapter.
+ *
+ * If -EBUSY is returned continue to call this function until 0 is returned.
+ */
+int hvcs_free_connection(uint32_t unit_address)
+{
+ long retval;
+ retval = plpar_hcall_norets(H_FREE_VTERM, unit_address);
+ return hvcs_convert(retval);
+}
+EXPORT_SYMBOL(hvcs_free_connection);