GRU Driver: driver initialization, file & vma ops

/*

 * SN Platform GRU Driver

 *

 *              FILE OPERATIONS & DRIVER INITIALIZATION

 *

 * This file supports the user system call for file open, close, mmap, etc.

 * This also incudes the driver initialization code.

 *

 *  Copyright (c) 2008 Silicon Graphics, Inc.  All Rights Reserved.

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA

 */

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/slab.h>

#include <linux/mm.h>

#include <linux/io.h>

#include <linux/smp_lock.h>

#include <linux/spinlock.h>

#include <linux/device.h>

#include <linux/miscdevice.h>

#include <linux/interrupt.h>

#include <linux/proc_fs.h>

#include <linux/uaccess.h>

#include "gru.h"

#include "grulib.h"

#include "grutables.h"

#if defined CONFIG_X86_64

#include <asm/genapic.h>

#include <asm/irq.h>

#define IS_UV()		is_uv_system()

#elif defined CONFIG_IA64

#include <asm/system.h>

#include <asm/sn/simulator.h>

/* temp support for running on hardware simulator */

#define IS_UV()		IS_MEDUSA() || ia64_platform_is("uv")

#else

#define IS_UV()		0

#endif

#include <asm/uv/uv_hub.h>

#include <asm/uv/uv_mmrs.h>

struct gru_blade_state *gru_base[GRU_MAX_BLADES] __read_mostly;

unsigned long gru_start_paddr, gru_end_paddr __read_mostly;

struct gru_stats_s gru_stats;

/* Guaranteed user available resources on each node */

static int max_user_cbrs, max_user_dsr_bytes;

static struct file_operations gru_fops;

static struct miscdevice gru_miscdev;

/*

 * gru_vma_close

 *

 * Called when unmapping a device mapping. Frees all gru resources

 * and tables belonging to the vma.

 */

static void gru_vma_close(struct vm_area_struct *vma)

{

	struct gru_vma_data *vdata;

	struct gru_thread_state *gts;

	struct list_head *entry, *next;

	if (!vma->vm_private_data)

		return;

	vdata = vma->vm_private_data;

	vma->vm_private_data = NULL;

	gru_dbg(grudev, "vma %p, file %p, vdata %p\n", vma, vma->vm_file,

				vdata);

	list_for_each_safe(entry, next, &vdata->vd_head) {

		gts =

		    list_entry(entry, struct gru_thread_state, ts_next);

		list_del(&gts->ts_next);

		mutex_lock(&gts->ts_ctxlock);

		if (gts->ts_gru)

			gru_unload_context(gts, 0);

		mutex_unlock(&gts->ts_ctxlock);

		gts_drop(gts);

	}

	kfree(vdata);

	STAT(vdata_free);

}

/*

 * gru_file_mmap

 *

 * Called when mmaping the device.  Initializes the vma with a fault handler

 * and private data structure necessary to allocate, track, and free the

 * underlying pages.

 */

static int gru_file_mmap(struct file *file, struct vm_area_struct *vma)

{

	if ((vma->vm_flags & (VM_SHARED | VM_WRITE)) != (VM_SHARED | VM_WRITE))

		return -EPERM;

	vma->vm_flags |=

	    (VM_IO | VM_DONTCOPY | VM_LOCKED | VM_DONTEXPAND | VM_PFNMAP |

			VM_RESERVED);

	vma->vm_page_prot = PAGE_SHARED;

	vma->vm_ops = &gru_vm_ops;

	vma->vm_private_data = gru_alloc_vma_data(vma, 0);

	if (!vma->vm_private_data)

		return -ENOMEM;

	gru_dbg(grudev, "file %p, vaddr 0x%lx, vma %p, vdata %p\n",

		file, vma->vm_start, vma, vma->vm_private_data);

	return 0;

}

/*

 * Create a new GRU context

 */

static int gru_create_new_context(unsigned long arg)

{

	struct gru_create_context_req req;

	struct vm_area_struct *vma;

	struct gru_vma_data *vdata;

	int ret = -EINVAL;

	if (copy_from_user(&req, (void __user *)arg, sizeof(req)))

		return -EFAULT;

	if (req.data_segment_bytes == 0 ||

				req.data_segment_bytes > max_user_dsr_bytes)

		return -EINVAL;

	if (!req.control_blocks || !req.maximum_thread_count ||

				req.control_blocks > max_user_cbrs)

		return -EINVAL;

	if (!(req.options & GRU_OPT_MISS_MASK))

		req.options |= GRU_OPT_MISS_FMM_INTR;

	down_write(&current->mm->mmap_sem);

	vma = gru_find_vma(req.gseg);

	if (vma) {

		vdata = vma->vm_private_data;

		vdata->vd_user_options = req.options;

		vdata->vd_dsr_au_count =

		    GRU_DS_BYTES_TO_AU(req.data_segment_bytes);

		vdata->vd_cbr_au_count = GRU_CB_COUNT_TO_AU(req.control_blocks);

		ret = 0;

	}

	up_write(&current->mm->mmap_sem);

	return ret;

}

/*

 * Get GRU configuration info (temp - for emulator testing)

 */

static long gru_get_config_info(unsigned long arg)

{

	struct gru_config_info info;

	int nodesperblade;

	if (num_online_nodes() > 1 &&

			(uv_node_to_blade_id(1) == uv_node_to_blade_id(0)))

		nodesperblade = 2;

	else

		nodesperblade = 1;

	info.cpus = num_online_cpus();

	info.nodes = num_online_nodes();

	info.blades = info.nodes / nodesperblade;

	info.chiplets = GRU_CHIPLETS_PER_BLADE * info.blades;

	if (copy_to_user((void __user *)arg, &info, sizeof(info)))

		return -EFAULT;

	return 0;

}

/*

 * Get GRU chiplet status

 */

static long gru_get_chiplet_status(unsigned long arg)

{

	struct gru_state *gru;

	struct gru_chiplet_info info;

	if (copy_from_user(&info, (void __user *)arg, sizeof(info)))

		return -EFAULT;

	if (info.node == -1)

		info.node = numa_node_id();

	if (info.node >= num_possible_nodes() ||

			info.chiplet >= GRU_CHIPLETS_PER_HUB ||

			info.node < 0 || info.chiplet < 0)

		return -EINVAL;

	info.blade = uv_node_to_blade_id(info.node);

	gru = get_gru(info.blade, info.chiplet);

	info.total_dsr_bytes = GRU_NUM_DSR_BYTES;

	info.total_cbr = GRU_NUM_CB;

	info.total_user_dsr_bytes = GRU_NUM_DSR_BYTES -

		gru->gs_reserved_dsr_bytes;

	info.total_user_cbr = GRU_NUM_CB - gru->gs_reserved_cbrs;

	info.free_user_dsr_bytes = hweight64(gru->gs_dsr_map) *

			GRU_DSR_AU_BYTES;

	info.free_user_cbr = hweight64(gru->gs_cbr_map) * GRU_CBR_AU_SIZE;

	if (copy_to_user((void __user *)arg, &info, sizeof(info)))

		return -EFAULT;

	return 0;

}

/*

 * gru_file_unlocked_ioctl

 *

 * Called to update file attributes via IOCTL calls.

 */

static long gru_file_unlocked_ioctl(struct file *file, unsigned int req,

				    unsigned long arg)

{

	int err = -EBADRQC;

	gru_dbg(grudev, "file %p\n", file);

	switch (req) {

	case GRU_CREATE_CONTEXT:

		err = gru_create_new_context(arg);

		break;

	case GRU_SET_TASK_SLICE:

		err = gru_set_task_slice(arg);

		break;

	case GRU_USER_GET_EXCEPTION_DETAIL:

		err = gru_get_exception_detail(arg);

		break;

	case GRU_USER_UNLOAD_CONTEXT:

		err = gru_user_unload_context(arg);

		break;

	case GRU_GET_CHIPLET_STATUS:

		err = gru_get_chiplet_status(arg);

		break;

	case GRU_USER_FLUSH_TLB:

		err = gru_user_flush_tlb(arg);

		break;

	case GRU_USER_CALL_OS:

		err = gru_handle_user_call_os(arg);

		break;

	case GRU_GET_CONFIG_INFO:

		err = gru_get_config_info(arg);

		break;

	}

	return err;

}

/*

 * Called at init time to build tables for all GRUs that are present in the

 * system.

 */

static void gru_init_chiplet(struct gru_state *gru, unsigned long paddr,

			     void *vaddr, int nid, int bid, int grunum)

{

	spin_lock_init(&gru->gs_lock);

	spin_lock_init(&gru->gs_asid_lock);

	gru->gs_gru_base_paddr = paddr;

	gru->gs_gru_base_vaddr = vaddr;

	gru->gs_gid = bid * GRU_CHIPLETS_PER_BLADE + grunum;

	gru->gs_blade = gru_base[bid];

	gru->gs_blade_id = bid;

	gru->gs_cbr_map = (GRU_CBR_AU == 64) ? ~0 : (1UL << GRU_CBR_AU) - 1;

	gru->gs_dsr_map = (1UL << GRU_DSR_AU) - 1;

	gru_tgh_flush_init(gru);

	gru_dbg(grudev, "bid %d, nid %d, gru %x, vaddr %p (0x%lx)\n",

		bid, nid, gru->gs_gid, gru->gs_gru_base_vaddr,

		gru->gs_gru_base_paddr);

	gru_kservices_init(gru);

}

static int gru_init_tables(unsigned long gru_base_paddr, void *gru_base_vaddr)

{

	int pnode, nid, bid, chip;

	int cbrs, dsrbytes, n;

	int order = get_order(sizeof(struct gru_blade_state));

	struct page *page;

	struct gru_state *gru;

	unsigned long paddr;

	void *vaddr;

	max_user_cbrs = GRU_NUM_CB;

	max_user_dsr_bytes = GRU_NUM_DSR_BYTES;

	for_each_online_node(nid) {

		bid = uv_node_to_blade_id(nid);

		pnode = uv_node_to_pnode(nid);

		if (gru_base[bid])

			continue;

		page = alloc_pages_node(nid, GFP_KERNEL, order);

		if (!page)

			goto fail;

		gru_base[bid] = page_address(page);

		memset(gru_base[bid], 0, sizeof(struct gru_blade_state));

		gru_base[bid]->bs_lru_gru = &gru_base[bid]->bs_grus[0];

		spin_lock_init(&gru_base[bid]->bs_lock);

		dsrbytes = 0;

		cbrs = 0;

		for (gru = gru_base[bid]->bs_grus, chip = 0;

		     		chip < GRU_CHIPLETS_PER_BLADE;

				chip++, gru++) {

			paddr = gru_chiplet_paddr(gru_base_paddr, pnode, chip);

			vaddr = gru_chiplet_vaddr(gru_base_vaddr, pnode, chip);

			gru_init_chiplet(gru, paddr, vaddr, bid, nid, chip);

			n = hweight64(gru->gs_cbr_map) * GRU_CBR_AU_SIZE;

			cbrs = max(cbrs, n);

			n = hweight64(gru->gs_dsr_map) * GRU_DSR_AU_BYTES;

			dsrbytes = max(dsrbytes, n);

		}

		max_user_cbrs = min(max_user_cbrs, cbrs);

		max_user_dsr_bytes = min(max_user_dsr_bytes, dsrbytes);

	}

	return 0;

fail:

	for (nid--; nid >= 0; nid--)

		free_pages((unsigned long)gru_base[nid], order);

	return -ENOMEM;

}

#ifdef CONFIG_IA64

static int get_base_irq(void)

{

	return IRQ_GRU;

}

#elif defined CONFIG_X86_64

static void noop(unsigned int irq)

{

}

static struct irq_chip gru_chip = {

	.name		= "gru",

	.mask		= noop,

	.unmask		= noop,

	.ack		= noop,

};

static int get_base_irq(void)

{

	set_irq_chip(IRQ_GRU, &gru_chip);

	set_irq_chip(IRQ_GRU + 1, &gru_chip);

	return IRQ_GRU;

}

#endif

/*

 * gru_init

 *

 * Called at boot or module load time to initialize the GRUs.

 */

static int __init gru_init(void)

{

	int ret, irq, chip;

	char id[10];

	void *gru_start_vaddr;

	if (!IS_UV())

		return 0;

#if defined CONFIG_IA64

	gru_start_paddr = 0xd000000000UL; /* ZZZZZZZZZZZZZZZZZZZ fixme */

#else

	gru_start_paddr = uv_read_local_mmr(UVH_RH_GAM_GRU_OVERLAY_CONFIG_MMR) &

				0x7fffffffffffUL;

#endif

	gru_start_vaddr = __va(gru_start_paddr);

	gru_end_paddr = gru_start_paddr + MAX_NUMNODES * GRU_SIZE;

	printk(KERN_INFO "GRU space: 0x%lx - 0x%lx\n",

	       gru_start_paddr, gru_end_paddr);

	irq = get_base_irq();

	for (chip = 0; chip < GRU_CHIPLETS_PER_BLADE; chip++) {

		ret = request_irq(irq + chip, gru_intr, 0, id, NULL);

		if (ret) {

			printk(KERN_ERR "%s: request_irq failed\n",

			       GRU_DRIVER_ID_STR);

			goto exit1;

		}

	}

	ret = misc_register(&gru_miscdev);

	if (ret) {

		printk(KERN_ERR "%s: misc_register failed\n",

		       GRU_DRIVER_ID_STR);

		goto exit1;

	}

	ret = gru_proc_init();

	if (ret) {

		printk(KERN_ERR "%s: proc init failed\n", GRU_DRIVER_ID_STR);

		goto exit2;

	}

	ret = gru_init_tables(gru_start_paddr, gru_start_vaddr);

	if (ret) {

		printk(KERN_ERR "%s: init tables failed\n", GRU_DRIVER_ID_STR);

		goto exit3;

	}

	printk(KERN_INFO "%s: v%s\n", GRU_DRIVER_ID_STR,

	       GRU_DRIVER_VERSION_STR);

	return 0;

exit3:

	gru_proc_exit();

exit2:

	misc_deregister(&gru_miscdev);

exit1:

	for (--chip; chip >= 0; chip--)

		free_irq(irq + chip, NULL);

	return ret;

}

static void __exit gru_exit(void)

{

	int i, bid;

	int order = get_order(sizeof(struct gru_state) *

			      GRU_CHIPLETS_PER_BLADE);

	for (i = 0; i < GRU_CHIPLETS_PER_BLADE; i++)

		free_irq(IRQ_GRU + i, NULL);

	for (bid = 0; bid < GRU_MAX_BLADES; bid++)

		free_pages((unsigned long)gru_base[bid], order);

	misc_deregister(&gru_miscdev);

	gru_proc_exit();

}

static struct file_operations gru_fops = {

	.owner		= THIS_MODULE,

	.unlocked_ioctl	= gru_file_unlocked_ioctl,

	.mmap		= gru_file_mmap,

};

static struct miscdevice gru_miscdev = {

	.minor		= MISC_DYNAMIC_MINOR,

	.name		= "gru",

	.fops		= &gru_fops,

};

struct vm_operations_struct gru_vm_ops = {

	.close		= gru_vma_close,

	.fault		= gru_fault,

};

module_init(gru_init);

module_exit(gru_exit);

module_param(options, ulong, 0644);

MODULE_PARM_DESC(options, "Various debug options");

MODULE_AUTHOR("Silicon Graphics, Inc.");

MODULE_LICENSE("GPL");

MODULE_DESCRIPTION(GRU_DRIVER_ID_STR GRU_DRIVER_VERSION_STR);

MODULE_VERSION(GRU_DRIVER_VERSION_STR);