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Diffstat (limited to '')
-rw-r--r-- | arch/powerpc/platforms/pseries/hvcserver.c | 239 |
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); |