diff options
Diffstat (limited to 'arch/tile/kernel/hardwall.c')
| -rw-r--r-- | arch/tile/kernel/hardwall.c | 1096 |
1 files changed, 0 insertions, 1096 deletions
diff --git a/arch/tile/kernel/hardwall.c b/arch/tile/kernel/hardwall.c deleted file mode 100644 index 2fd1694ac1d0..000000000000 --- a/arch/tile/kernel/hardwall.c +++ /dev/null @@ -1,1096 +0,0 @@ -/* - * Copyright 2010 Tilera Corporation. 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, version 2. - * - * 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, GOOD TITLE or - * NON INFRINGEMENT. See the GNU General Public License for - * more details. - */ - -#include <linux/fs.h> -#include <linux/proc_fs.h> -#include <linux/seq_file.h> -#include <linux/rwsem.h> -#include <linux/kprobes.h> -#include <linux/sched.h> -#include <linux/hardirq.h> -#include <linux/uaccess.h> -#include <linux/smp.h> -#include <linux/cdev.h> -#include <linux/compat.h> -#include <asm/hardwall.h> -#include <asm/traps.h> -#include <asm/siginfo.h> -#include <asm/irq_regs.h> - -#include <arch/interrupts.h> -#include <arch/spr_def.h> - - -/* - * Implement a per-cpu "hardwall" resource class such as UDN or IPI. - * We use "hardwall" nomenclature throughout for historical reasons. - * The lock here controls access to the list data structure as well as - * to the items on the list. - */ -struct hardwall_type { - int index; - int is_xdn; - int is_idn; - int disabled; - const char *name; - struct list_head list; - spinlock_t lock; - struct proc_dir_entry *proc_dir; -}; - -enum hardwall_index { - HARDWALL_UDN = 0, -#ifndef __tilepro__ - HARDWALL_IDN = 1, - HARDWALL_IPI = 2, -#endif - _HARDWALL_TYPES -}; - -static struct hardwall_type hardwall_types[] = { - { /* user-space access to UDN */ - 0, - 1, - 0, - 0, - "udn", - LIST_HEAD_INIT(hardwall_types[HARDWALL_UDN].list), - __SPIN_LOCK_UNLOCKED(hardwall_types[HARDWALL_UDN].lock), - NULL - }, -#ifndef __tilepro__ - { /* user-space access to IDN */ - 1, - 1, - 1, - 1, /* disabled pending hypervisor support */ - "idn", - LIST_HEAD_INIT(hardwall_types[HARDWALL_IDN].list), - __SPIN_LOCK_UNLOCKED(hardwall_types[HARDWALL_IDN].lock), - NULL - }, - { /* access to user-space IPI */ - 2, - 0, - 0, - 0, - "ipi", - LIST_HEAD_INIT(hardwall_types[HARDWALL_IPI].list), - __SPIN_LOCK_UNLOCKED(hardwall_types[HARDWALL_IPI].lock), - NULL - }, -#endif -}; - -/* - * This data structure tracks the cpu data, etc., associated - * one-to-one with a "struct file *" from opening a hardwall device file. - * Note that the file's private data points back to this structure. - */ -struct hardwall_info { - struct list_head list; /* for hardwall_types.list */ - struct list_head task_head; /* head of tasks in this hardwall */ - struct hardwall_type *type; /* type of this resource */ - struct cpumask cpumask; /* cpus reserved */ - int id; /* integer id for this hardwall */ - int teardown_in_progress; /* are we tearing this one down? */ - - /* Remaining fields only valid for user-network resources. */ - int ulhc_x; /* upper left hand corner x coord */ - int ulhc_y; /* upper left hand corner y coord */ - int width; /* rectangle width */ - int height; /* rectangle height */ -#if CHIP_HAS_REV1_XDN() - atomic_t xdn_pending_count; /* cores in phase 1 of drain */ -#endif -}; - - -/* /proc/tile/hardwall */ -static struct proc_dir_entry *hardwall_proc_dir; - -/* Functions to manage files in /proc/tile/hardwall. */ -static void hardwall_add_proc(struct hardwall_info *); -static void hardwall_remove_proc(struct hardwall_info *); - -/* Allow disabling UDN access. */ -static int __init noudn(char *str) -{ - pr_info("User-space UDN access is disabled\n"); - hardwall_types[HARDWALL_UDN].disabled = 1; - return 0; -} -early_param("noudn", noudn); - -#ifndef __tilepro__ -/* Allow disabling IDN access. */ -static int __init noidn(char *str) -{ - pr_info("User-space IDN access is disabled\n"); - hardwall_types[HARDWALL_IDN].disabled = 1; - return 0; -} -early_param("noidn", noidn); - -/* Allow disabling IPI access. */ -static int __init noipi(char *str) -{ - pr_info("User-space IPI access is disabled\n"); - hardwall_types[HARDWALL_IPI].disabled = 1; - return 0; -} -early_param("noipi", noipi); -#endif - - -/* - * Low-level primitives for UDN/IDN - */ - -#ifdef __tilepro__ -#define mtspr_XDN(hwt, name, val) \ - do { (void)(hwt); __insn_mtspr(SPR_UDN_##name, (val)); } while (0) -#define mtspr_MPL_XDN(hwt, name, val) \ - do { (void)(hwt); __insn_mtspr(SPR_MPL_UDN_##name, (val)); } while (0) -#define mfspr_XDN(hwt, name) \ - ((void)(hwt), __insn_mfspr(SPR_UDN_##name)) -#else -#define mtspr_XDN(hwt, name, val) \ - do { \ - if ((hwt)->is_idn) \ - __insn_mtspr(SPR_IDN_##name, (val)); \ - else \ - __insn_mtspr(SPR_UDN_##name, (val)); \ - } while (0) -#define mtspr_MPL_XDN(hwt, name, val) \ - do { \ - if ((hwt)->is_idn) \ - __insn_mtspr(SPR_MPL_IDN_##name, (val)); \ - else \ - __insn_mtspr(SPR_MPL_UDN_##name, (val)); \ - } while (0) -#define mfspr_XDN(hwt, name) \ - ((hwt)->is_idn ? __insn_mfspr(SPR_IDN_##name) : __insn_mfspr(SPR_UDN_##name)) -#endif - -/* Set a CPU bit if the CPU is online. */ -#define cpu_online_set(cpu, dst) do { \ - if (cpu_online(cpu)) \ - cpumask_set_cpu(cpu, dst); \ -} while (0) - - -/* Does the given rectangle contain the given x,y coordinate? */ -static int contains(struct hardwall_info *r, int x, int y) -{ - return (x >= r->ulhc_x && x < r->ulhc_x + r->width) && - (y >= r->ulhc_y && y < r->ulhc_y + r->height); -} - -/* Compute the rectangle parameters and validate the cpumask. */ -static int check_rectangle(struct hardwall_info *r, struct cpumask *mask) -{ - int x, y, cpu, ulhc, lrhc; - - /* The first cpu is the ULHC, the last the LRHC. */ - ulhc = find_first_bit(cpumask_bits(mask), nr_cpumask_bits); - lrhc = find_last_bit(cpumask_bits(mask), nr_cpumask_bits); - - /* Compute the rectangle attributes from the cpus. */ - r->ulhc_x = cpu_x(ulhc); - r->ulhc_y = cpu_y(ulhc); - r->width = cpu_x(lrhc) - r->ulhc_x + 1; - r->height = cpu_y(lrhc) - r->ulhc_y + 1; - - /* Width and height must be positive */ - if (r->width <= 0 || r->height <= 0) - return -EINVAL; - - /* Confirm that the cpumask is exactly the rectangle. */ - for (y = 0, cpu = 0; y < smp_height; ++y) - for (x = 0; x < smp_width; ++x, ++cpu) - if (cpumask_test_cpu(cpu, mask) != contains(r, x, y)) - return -EINVAL; - - /* - * Note that offline cpus can't be drained when this user network - * rectangle eventually closes. We used to detect this - * situation and print a warning, but it annoyed users and - * they ignored it anyway, so now we just return without a - * warning. - */ - return 0; -} - -/* - * Hardware management of hardwall setup, teardown, trapping, - * and enabling/disabling PL0 access to the networks. - */ - -/* Bit field values to mask together for writes to SPR_XDN_DIRECTION_PROTECT */ -enum direction_protect { - N_PROTECT = (1 << 0), - E_PROTECT = (1 << 1), - S_PROTECT = (1 << 2), - W_PROTECT = (1 << 3), - C_PROTECT = (1 << 4), -}; - -static inline int xdn_which_interrupt(struct hardwall_type *hwt) -{ -#ifndef __tilepro__ - if (hwt->is_idn) - return INT_IDN_FIREWALL; -#endif - return INT_UDN_FIREWALL; -} - -static void enable_firewall_interrupts(struct hardwall_type *hwt) -{ - arch_local_irq_unmask_now(xdn_which_interrupt(hwt)); -} - -static void disable_firewall_interrupts(struct hardwall_type *hwt) -{ - arch_local_irq_mask_now(xdn_which_interrupt(hwt)); -} - -/* Set up hardwall on this cpu based on the passed hardwall_info. */ -static void hardwall_setup_func(void *info) -{ - struct hardwall_info *r = info; - struct hardwall_type *hwt = r->type; - - int cpu = smp_processor_id(); /* on_each_cpu disables preemption */ - int x = cpu_x(cpu); - int y = cpu_y(cpu); - int bits = 0; - if (x == r->ulhc_x) - bits |= W_PROTECT; - if (x == r->ulhc_x + r->width - 1) - bits |= E_PROTECT; - if (y == r->ulhc_y) - bits |= N_PROTECT; - if (y == r->ulhc_y + r->height - 1) - bits |= S_PROTECT; - BUG_ON(bits == 0); - mtspr_XDN(hwt, DIRECTION_PROTECT, bits); - enable_firewall_interrupts(hwt); -} - -/* Set up all cpus on edge of rectangle to enable/disable hardwall SPRs. */ -static void hardwall_protect_rectangle(struct hardwall_info *r) -{ - int x, y, cpu, delta; - struct cpumask rect_cpus; - - cpumask_clear(&rect_cpus); - - /* First include the top and bottom edges */ - cpu = r->ulhc_y * smp_width + r->ulhc_x; - delta = (r->height - 1) * smp_width; - for (x = 0; x < r->width; ++x, ++cpu) { - cpu_online_set(cpu, &rect_cpus); - cpu_online_set(cpu + delta, &rect_cpus); - } - - /* Then the left and right edges */ - cpu -= r->width; - delta = r->width - 1; - for (y = 0; y < r->height; ++y, cpu += smp_width) { - cpu_online_set(cpu, &rect_cpus); - cpu_online_set(cpu + delta, &rect_cpus); - } - - /* Then tell all the cpus to set up their protection SPR */ - on_each_cpu_mask(&rect_cpus, hardwall_setup_func, r, 1); -} - -/* Entered from INT_xDN_FIREWALL interrupt vector with irqs disabled. */ -void __kprobes do_hardwall_trap(struct pt_regs* regs, int fault_num) -{ - struct hardwall_info *rect; - struct hardwall_type *hwt; - struct task_struct *p; - struct siginfo info; - int cpu = smp_processor_id(); - int found_processes; - struct pt_regs *old_regs = set_irq_regs(regs); - - irq_enter(); - - /* Figure out which network trapped. */ - switch (fault_num) { -#ifndef __tilepro__ - case INT_IDN_FIREWALL: - hwt = &hardwall_types[HARDWALL_IDN]; - break; -#endif - case INT_UDN_FIREWALL: - hwt = &hardwall_types[HARDWALL_UDN]; - break; - default: - BUG(); - } - BUG_ON(hwt->disabled); - - /* This tile trapped a network access; find the rectangle. */ - spin_lock(&hwt->lock); - list_for_each_entry(rect, &hwt->list, list) { - if (cpumask_test_cpu(cpu, &rect->cpumask)) - break; - } - - /* - * It shouldn't be possible not to find this cpu on the - * rectangle list, since only cpus in rectangles get hardwalled. - * The hardwall is only removed after the user network is drained. - */ - BUG_ON(&rect->list == &hwt->list); - - /* - * If we already started teardown on this hardwall, don't worry; - * the abort signal has been sent and we are just waiting for things - * to quiesce. - */ - if (rect->teardown_in_progress) { - pr_notice("cpu %d: detected %s hardwall violation %#lx while teardown already in progress\n", - cpu, hwt->name, - (long)mfspr_XDN(hwt, DIRECTION_PROTECT)); - goto done; - } - - /* - * Kill off any process that is activated in this rectangle. - * We bypass security to deliver the signal, since it must be - * one of the activated processes that generated the user network - * message that caused this trap, and all the activated - * processes shared a single open file so are pretty tightly - * bound together from a security point of view to begin with. - */ - rect->teardown_in_progress = 1; - wmb(); /* Ensure visibility of rectangle before notifying processes. */ - pr_notice("cpu %d: detected %s hardwall violation %#lx...\n", - cpu, hwt->name, (long)mfspr_XDN(hwt, DIRECTION_PROTECT)); - info.si_signo = SIGILL; - info.si_errno = 0; - info.si_code = ILL_HARDWALL; - found_processes = 0; - list_for_each_entry(p, &rect->task_head, - thread.hardwall[hwt->index].list) { - BUG_ON(p->thread.hardwall[hwt->index].info != rect); - if (!(p->flags & PF_EXITING)) { - found_processes = 1; - pr_notice("hardwall: killing %d\n", p->pid); - do_send_sig_info(info.si_signo, &info, p, false); - } - } - if (!found_processes) - pr_notice("hardwall: no associated processes!\n"); - - done: - spin_unlock(&hwt->lock); - - /* - * We have to disable firewall interrupts now, or else when we - * return from this handler, we will simply re-interrupt back to - * it. However, we can't clear the protection bits, since we - * haven't yet drained the network, and that would allow packets - * to cross out of the hardwall region. - */ - disable_firewall_interrupts(hwt); - - irq_exit(); - set_irq_regs(old_regs); -} - -/* Allow access from user space to the user network. */ -void grant_hardwall_mpls(struct hardwall_type *hwt) -{ -#ifndef __tilepro__ - if (!hwt->is_xdn) { - __insn_mtspr(SPR_MPL_IPI_0_SET_0, 1); - return; - } -#endif - mtspr_MPL_XDN(hwt, ACCESS_SET_0, 1); - mtspr_MPL_XDN(hwt, AVAIL_SET_0, 1); - mtspr_MPL_XDN(hwt, COMPLETE_SET_0, 1); - mtspr_MPL_XDN(hwt, TIMER_SET_0, 1); -#if !CHIP_HAS_REV1_XDN() - mtspr_MPL_XDN(hwt, REFILL_SET_0, 1); - mtspr_MPL_XDN(hwt, CA_SET_0, 1); -#endif -} - -/* Deny access from user space to the user network. */ -void restrict_hardwall_mpls(struct hardwall_type *hwt) -{ -#ifndef __tilepro__ - if (!hwt->is_xdn) { - __insn_mtspr(SPR_MPL_IPI_0_SET_1, 1); - return; - } -#endif - mtspr_MPL_XDN(hwt, ACCESS_SET_1, 1); - mtspr_MPL_XDN(hwt, AVAIL_SET_1, 1); - mtspr_MPL_XDN(hwt, COMPLETE_SET_1, 1); - mtspr_MPL_XDN(hwt, TIMER_SET_1, 1); -#if !CHIP_HAS_REV1_XDN() - mtspr_MPL_XDN(hwt, REFILL_SET_1, 1); - mtspr_MPL_XDN(hwt, CA_SET_1, 1); -#endif -} - -/* Restrict or deny as necessary for the task we're switching to. */ -void hardwall_switch_tasks(struct task_struct *prev, - struct task_struct *next) -{ - int i; - for (i = 0; i < HARDWALL_TYPES; ++i) { - if (prev->thread.hardwall[i].info != NULL) { - if (next->thread.hardwall[i].info == NULL) - restrict_hardwall_mpls(&hardwall_types[i]); - } else if (next->thread.hardwall[i].info != NULL) { - grant_hardwall_mpls(&hardwall_types[i]); - } - } -} - -/* Does this task have the right to IPI the given cpu? */ -int hardwall_ipi_valid(int cpu) -{ -#ifdef __tilegx__ - struct hardwall_info *info = - current->thread.hardwall[HARDWALL_IPI].info; - return info && cpumask_test_cpu(cpu, &info->cpumask); -#else - return 0; -#endif -} - -/* - * Code to create, activate, deactivate, and destroy hardwall resources. - */ - -/* Create a hardwall for the given resource */ -static struct hardwall_info *hardwall_create(struct hardwall_type *hwt, - size_t size, - const unsigned char __user *bits) -{ - struct hardwall_info *iter, *info; - struct cpumask mask; - unsigned long flags; - int rc; - - /* Reject crazy sizes out of hand, a la sys_mbind(). */ - if (size > PAGE_SIZE) - return ERR_PTR(-EINVAL); - - /* Copy whatever fits into a cpumask. */ - if (copy_from_user(&mask, bits, min(sizeof(struct cpumask), size))) - return ERR_PTR(-EFAULT); - - /* - * If the size was short, clear the rest of the mask; - * otherwise validate that the rest of the user mask was zero - * (we don't try hard to be efficient when validating huge masks). - */ - if (size < sizeof(struct cpumask)) { - memset((char *)&mask + size, 0, sizeof(struct cpumask) - size); - } else if (size > sizeof(struct cpumask)) { - size_t i; - for (i = sizeof(struct cpumask); i < size; ++i) { - char c; - if (get_user(c, &bits[i])) - return ERR_PTR(-EFAULT); - if (c) - return ERR_PTR(-EINVAL); - } - } - - /* Allocate a new hardwall_info optimistically. */ - info = kmalloc(sizeof(struct hardwall_info), - GFP_KERNEL | __GFP_ZERO); - if (info == NULL) - return ERR_PTR(-ENOMEM); - INIT_LIST_HEAD(&info->task_head); - info->type = hwt; - - /* Compute the rectangle size and validate that it's plausible. */ - cpumask_copy(&info->cpumask, &mask); - info->id = find_first_bit(cpumask_bits(&mask), nr_cpumask_bits); - if (hwt->is_xdn) { - rc = check_rectangle(info, &mask); - if (rc != 0) { - kfree(info); - return ERR_PTR(rc); - } - } - - /* - * Eliminate cpus that are not part of this Linux client. - * Note that this allows for configurations that we might not want to - * support, such as one client on every even cpu, another client on - * every odd cpu. - */ - cpumask_and(&info->cpumask, &info->cpumask, cpu_online_mask); - - /* Confirm it doesn't overlap and add it to the list. */ - spin_lock_irqsave(&hwt->lock, flags); - list_for_each_entry(iter, &hwt->list, list) { - if (cpumask_intersects(&iter->cpumask, &info->cpumask)) { - spin_unlock_irqrestore(&hwt->lock, flags); - kfree(info); - return ERR_PTR(-EBUSY); - } - } - list_add_tail(&info->list, &hwt->list); - spin_unlock_irqrestore(&hwt->lock, flags); - - /* Set up appropriate hardwalling on all affected cpus. */ - if (hwt->is_xdn) - hardwall_protect_rectangle(info); - - /* Create a /proc/tile/hardwall entry. */ - hardwall_add_proc(info); - - return info; -} - -/* Activate a given hardwall on this cpu for this process. */ -static int hardwall_activate(struct hardwall_info *info) -{ - int cpu; - unsigned long flags; - struct task_struct *p = current; - struct thread_struct *ts = &p->thread; - struct hardwall_type *hwt; - - /* Require a hardwall. */ - if (info == NULL) - return -ENODATA; - - /* Not allowed to activate a hardwall that is being torn down. */ - if (info->teardown_in_progress) - return -EINVAL; - - /* - * Get our affinity; if we're not bound to this tile uniquely, - * we can't access the network registers. - */ - if (cpumask_weight(&p->cpus_allowed) != 1) - return -EPERM; - - /* Make sure we are bound to a cpu assigned to this resource. */ - cpu = smp_processor_id(); - BUG_ON(cpumask_first(&p->cpus_allowed) != cpu); - if (!cpumask_test_cpu(cpu, &info->cpumask)) - return -EINVAL; - - /* If we are already bound to this hardwall, it's a no-op. */ - hwt = info->type; - if (ts->hardwall[hwt->index].info) { - BUG_ON(ts->hardwall[hwt->index].info != info); - return 0; - } - - /* Success! This process gets to use the resource on this cpu. */ - ts->hardwall[hwt->index].info = info; - spin_lock_irqsave(&hwt->lock, flags); - list_add(&ts->hardwall[hwt->index].list, &info->task_head); - spin_unlock_irqrestore(&hwt->lock, flags); - grant_hardwall_mpls(hwt); - printk(KERN_DEBUG "Pid %d (%s) activated for %s hardwall: cpu %d\n", - p->pid, p->comm, hwt->name, cpu); - return 0; -} - -/* - * Deactivate a task's hardwall. Must hold lock for hardwall_type. - * This method may be called from exit_thread(), so we don't want to - * rely on too many fields of struct task_struct still being valid. - * We assume the cpus_allowed, pid, and comm fields are still valid. - */ -static void _hardwall_deactivate(struct hardwall_type *hwt, - struct task_struct *task) -{ - struct thread_struct *ts = &task->thread; - - if (cpumask_weight(&task->cpus_allowed) != 1) { - pr_err("pid %d (%s) releasing %s hardwall with an affinity mask containing %d cpus!\n", - task->pid, task->comm, hwt->name, - cpumask_weight(&task->cpus_allowed)); - BUG(); - } - - BUG_ON(ts->hardwall[hwt->index].info == NULL); - ts->hardwall[hwt->index].info = NULL; - list_del(&ts->hardwall[hwt->index].list); - if (task == current) - restrict_hardwall_mpls(hwt); -} - -/* Deactivate a task's hardwall. */ -static int hardwall_deactivate(struct hardwall_type *hwt, - struct task_struct *task) -{ - unsigned long flags; - int activated; - - spin_lock_irqsave(&hwt->lock, flags); - activated = (task->thread.hardwall[hwt->index].info != NULL); - if (activated) - _hardwall_deactivate(hwt, task); - spin_unlock_irqrestore(&hwt->lock, flags); - - if (!activated) - return -EINVAL; - - printk(KERN_DEBUG "Pid %d (%s) deactivated for %s hardwall: cpu %d\n", - task->pid, task->comm, hwt->name, raw_smp_processor_id()); - return 0; -} - -void hardwall_deactivate_all(struct task_struct *task) -{ - int i; - for (i = 0; i < HARDWALL_TYPES; ++i) - if (task->thread.hardwall[i].info) - hardwall_deactivate(&hardwall_types[i], task); -} - -/* Stop the switch before draining the network. */ -static void stop_xdn_switch(void *arg) -{ -#if !CHIP_HAS_REV1_XDN() - /* Freeze the switch and the demux. */ - __insn_mtspr(SPR_UDN_SP_FREEZE, - SPR_UDN_SP_FREEZE__SP_FRZ_MASK | - SPR_UDN_SP_FREEZE__DEMUX_FRZ_MASK | - SPR_UDN_SP_FREEZE__NON_DEST_EXT_MASK); -#else - /* - * Drop all packets bound for the core or off the edge. - * We rely on the normal hardwall protection setup code - * to have set the low four bits to trigger firewall interrupts, - * and shift those bits up to trigger "drop on send" semantics, - * plus adding "drop on send to core" for all switches. - * In practice it seems the switches latch the DIRECTION_PROTECT - * SPR so they won't start dropping if they're already - * delivering the last message to the core, but it doesn't - * hurt to enable it here. - */ - struct hardwall_type *hwt = arg; - unsigned long protect = mfspr_XDN(hwt, DIRECTION_PROTECT); - mtspr_XDN(hwt, DIRECTION_PROTECT, (protect | C_PROTECT) << 5); -#endif -} - -static void empty_xdn_demuxes(struct hardwall_type *hwt) -{ -#ifndef __tilepro__ - if (hwt->is_idn) { - while (__insn_mfspr(SPR_IDN_DATA_AVAIL) & (1 << 0)) - (void) __tile_idn0_receive(); - while (__insn_mfspr(SPR_IDN_DATA_AVAIL) & (1 << 1)) - (void) __tile_idn1_receive(); - return; - } -#endif - while (__insn_mfspr(SPR_UDN_DATA_AVAIL) & (1 << 0)) - (void) __tile_udn0_receive(); - while (__insn_mfspr(SPR_UDN_DATA_AVAIL) & (1 << 1)) - (void) __tile_udn1_receive(); - while (__insn_mfspr(SPR_UDN_DATA_AVAIL) & (1 << 2)) - (void) __tile_udn2_receive(); - while (__insn_mfspr(SPR_UDN_DATA_AVAIL) & (1 << 3)) - (void) __tile_udn3_receive(); -} - -/* Drain all the state from a stopped switch. */ -static void drain_xdn_switch(void *arg) -{ - struct hardwall_info *info = arg; - struct hardwall_type *hwt = info->type; - -#if CHIP_HAS_REV1_XDN() - /* - * The switches have been configured to drop any messages - * destined for cores (or off the edge of the rectangle). - * But the current message may continue to be delivered, - * so we wait until all the cores have finished any pending - * messages before we stop draining. - */ - int pending = mfspr_XDN(hwt, PENDING); - while (pending--) { - empty_xdn_demuxes(hwt); - if (hwt->is_idn) - __tile_idn_send(0); - else - __tile_udn_send(0); - } - atomic_dec(&info->xdn_pending_count); - while (atomic_read(&info->xdn_pending_count)) - empty_xdn_demuxes(hwt); -#else - int i; - int from_tile_words, ca_count; - - /* Empty out the 5 switch point fifos. */ - for (i = 0; i < 5; i++) { - int words, j; - __insn_mtspr(SPR_UDN_SP_FIFO_SEL, i); - words = __insn_mfspr(SPR_UDN_SP_STATE) & 0xF; - for (j = 0; j < words; j++) - (void) __insn_mfspr(SPR_UDN_SP_FIFO_DATA); - BUG_ON((__insn_mfspr(SPR_UDN_SP_STATE) & 0xF) != 0); - } - - /* Dump out the 3 word fifo at top. */ - from_tile_words = (__insn_mfspr(SPR_UDN_DEMUX_STATUS) >> 10) & 0x3; - for (i = 0; i < from_tile_words; i++) - (void) __insn_mfspr(SPR_UDN_DEMUX_WRITE_FIFO); - - /* Empty out demuxes. */ - empty_xdn_demuxes(hwt); - - /* Empty out catch all. */ - ca_count = __insn_mfspr(SPR_UDN_DEMUX_CA_COUNT); - for (i = 0; i < ca_count; i++) - (void) __insn_mfspr(SPR_UDN_CA_DATA); - BUG_ON(__insn_mfspr(SPR_UDN_DEMUX_CA_COUNT) != 0); - - /* Clear demux logic. */ - __insn_mtspr(SPR_UDN_DEMUX_CTL, 1); - - /* - * Write switch state; experimentation indicates that 0xc3000 - * is an idle switch point. - */ - for (i = 0; i < 5; i++) { - __insn_mtspr(SPR_UDN_SP_FIFO_SEL, i); - __insn_mtspr(SPR_UDN_SP_STATE, 0xc3000); - } -#endif -} - -/* Reset random XDN state registers at boot up and during hardwall teardown. */ -static void reset_xdn_network_state(struct hardwall_type *hwt) -{ - if (hwt->disabled) - return; - - /* Clear out other random registers so we have a clean slate. */ - mtspr_XDN(hwt, DIRECTION_PROTECT, 0); - mtspr_XDN(hwt, AVAIL_EN, 0); - mtspr_XDN(hwt, DEADLOCK_TIMEOUT, 0); - -#if !CHIP_HAS_REV1_XDN() - /* Reset UDN coordinates to their standard value */ - { - unsigned int cpu = smp_processor_id(); - unsigned int x = cpu_x(cpu); - unsigned int y = cpu_y(cpu); - __insn_mtspr(SPR_UDN_TILE_COORD, (x << 18) | (y << 7)); - } - - /* Set demux tags to predefined values and enable them. */ - __insn_mtspr(SPR_UDN_TAG_VALID, 0xf); - __insn_mtspr(SPR_UDN_TAG_0, (1 << 0)); - __insn_mtspr(SPR_UDN_TAG_1, (1 << 1)); - __insn_mtspr(SPR_UDN_TAG_2, (1 << 2)); - __insn_mtspr(SPR_UDN_TAG_3, (1 << 3)); - - /* Set other rev0 random registers to a clean state. */ - __insn_mtspr(SPR_UDN_REFILL_EN, 0); - __insn_mtspr(SPR_UDN_DEMUX_QUEUE_SEL, 0); - __insn_mtspr(SPR_UDN_SP_FIFO_SEL, 0); - - /* Start the switch and demux. */ - __insn_mtspr(SPR_UDN_SP_FREEZE, 0); -#endif -} - -void reset_network_state(void) -{ - reset_xdn_network_state(&hardwall_types[HARDWALL_UDN]); -#ifndef __tilepro__ - reset_xdn_network_state(&hardwall_types[HARDWALL_IDN]); -#endif -} - -/* Restart an XDN switch after draining. */ -static void restart_xdn_switch(void *arg) -{ - struct hardwall_type *hwt = arg; - -#if CHIP_HAS_REV1_XDN() - /* One last drain step to avoid races with injection and draining. */ - empty_xdn_demuxes(hwt); -#endif - - reset_xdn_network_state(hwt); - - /* Disable firewall interrupts. */ - disable_firewall_interrupts(hwt); -} - -/* Last reference to a hardwall is gone, so clear the network. */ -static void hardwall_destroy(struct hardwall_info *info) -{ - struct task_struct *task; - struct hardwall_type *hwt; - unsigned long flags; - - /* Make sure this file actually represents a hardwall. */ - if (info == NULL) - return; - - /* - * Deactivate any remaining tasks. It's possible to race with - * some other thread that is exiting and hasn't yet called - * deactivate (when freeing its thread_info), so we carefully - * deactivate any remaining tasks before freeing the - * hardwall_info object itself. - */ - hwt = info->type; - info->teardown_in_progress = 1; - spin_lock_irqsave(&hwt->lock, flags); - list_for_each_entry(task, &info->task_head, - thread.hardwall[hwt->index].list) - _hardwall_deactivate(hwt, task); - spin_unlock_irqrestore(&hwt->lock, flags); - - if (hwt->is_xdn) { - /* Configure the switches for draining the user network. */ - printk(KERN_DEBUG - "Clearing %s hardwall rectangle %dx%d %d,%d\n", - hwt->name, info->width, info->height, - info->ulhc_x, info->ulhc_y); - on_each_cpu_mask(&info->cpumask, stop_xdn_switch, hwt, 1); - - /* Drain the network. */ -#if CHIP_HAS_REV1_XDN() - atomic_set(&info->xdn_pending_count, - cpumask_weight(&info->cpumask)); - on_each_cpu_mask(&info->cpumask, drain_xdn_switch, info, 0); -#else - on_each_cpu_mask(&info->cpumask, drain_xdn_switch, info, 1); -#endif - - /* Restart switch and disable firewall. */ - on_each_cpu_mask(&info->cpumask, restart_xdn_switch, hwt, 1); - } - - /* Remove the /proc/tile/hardwall entry. */ - hardwall_remove_proc(info); - - /* Now free the hardwall from the list. */ - spin_lock_irqsave(&hwt->lock, flags); - BUG_ON(!list_empty(&info->task_head)); - list_del(&info->list); - spin_unlock_irqrestore(&hwt->lock, flags); - kfree(info); -} - - -static int hardwall_proc_show(struct seq_file *sf, void *v) -{ - struct hardwall_info *info = sf->private; - - seq_printf(sf, "%*pbl\n", cpumask_pr_args(&info->cpumask)); - return 0; -} - -static int hardwall_proc_open(struct inode *inode, - struct file *file) -{ - return single_open(file, hardwall_proc_show, PDE_DATA(inode)); -} - -static const struct file_operations hardwall_proc_fops = { - .open = hardwall_proc_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static void hardwall_add_proc(struct hardwall_info *info) -{ - char buf[64]; - snprintf(buf, sizeof(buf), "%d", info->id); - proc_create_data(buf, 0444, info->type->proc_dir, - &hardwall_proc_fops, info); -} - -static void hardwall_remove_proc(struct hardwall_info *info) -{ - char buf[64]; - snprintf(buf, sizeof(buf), "%d", info->id); - remove_proc_entry(buf, info->type->proc_dir); -} - -int proc_pid_hardwall(struct seq_file *m, struct pid_namespace *ns, - struct pid *pid, struct task_struct *task) -{ - int i; - int n = 0; - for (i = 0; i < HARDWALL_TYPES; ++i) { - struct hardwall_info *info = task->thread.hardwall[i].info; - if (info) - seq_printf(m, "%s: %d\n", info->type->name, info->id); - } - return n; -} - -void proc_tile_hardwall_init(struct proc_dir_entry *root) -{ - int i; - for (i = 0; i < HARDWALL_TYPES; ++i) { - struct hardwall_type *hwt = &hardwall_types[i]; - if (hwt->disabled) - continue; - if (hardwall_proc_dir == NULL) - hardwall_proc_dir = proc_mkdir("hardwall", root); - hwt->proc_dir = proc_mkdir(hwt->name, hardwall_proc_dir); - } -} - - -/* - * Character device support via ioctl/close. - */ - -static long hardwall_ioctl(struct file *file, unsigned int a, unsigned long b) -{ - struct hardwall_info *info = file->private_data; - int minor = iminor(file->f_mapping->host); - struct hardwall_type* hwt; - - if (_IOC_TYPE(a) != HARDWALL_IOCTL_BASE) - return -EINVAL; - - BUILD_BUG_ON(HARDWALL_TYPES != _HARDWALL_TYPES); - BUILD_BUG_ON(HARDWALL_TYPES != - sizeof(hardwall_types)/sizeof(hardwall_types[0])); - - if (minor < 0 || minor >= HARDWALL_TYPES) - return -EINVAL; - hwt = &hardwall_types[minor]; - WARN_ON(info && hwt != info->type); - - switch (_IOC_NR(a)) { - case _HARDWALL_CREATE: - if (hwt->disabled) - return -ENOSYS; - if (info != NULL) - return -EALREADY; - info = hardwall_create(hwt, _IOC_SIZE(a), - (const unsigned char __user *)b); - if (IS_ERR(info)) - return PTR_ERR(info); - file->private_data = info; - return 0; - - case _HARDWALL_ACTIVATE: - return hardwall_activate(info); - - case _HARDWALL_DEACTIVATE: - if (current->thread.hardwall[hwt->index].info != info) - return -EINVAL; - return hardwall_deactivate(hwt, current); - - case _HARDWALL_GET_ID: - return info ? info->id : -EINVAL; - - default: - return -EINVAL; - } -} - -#ifdef CONFIG_COMPAT -static long hardwall_compat_ioctl(struct file *file, - unsigned int a, unsigned long b) -{ - /* Sign-extend the argument so it can be used as a pointer. */ - return hardwall_ioctl(file, a, (unsigned long)compat_ptr(b)); -} -#endif - -/* The user process closed the file; revoke access to user networks. */ -static int hardwall_flush(struct file *file, fl_owner_t owner) -{ - struct hardwall_info *info = file->private_data; - struct task_struct *task, *tmp; - unsigned long flags; - - if (info) { - /* - * NOTE: if multiple threads are activated on this hardwall - * file, the other threads will continue having access to the - * user network until they are context-switched out and back - * in again. - * - * NOTE: A NULL files pointer means the task is being torn - * down, so in that case we also deactivate it. - */ - struct hardwall_type *hwt = info->type; - spin_lock_irqsave(&hwt->lock, flags); - list_for_each_entry_safe(task, tmp, &info->task_head, - thread.hardwall[hwt->index].list) { - if (task->files == owner || task->files == NULL) - _hardwall_deactivate(hwt, task); - } - spin_unlock_irqrestore(&hwt->lock, flags); - } - - return 0; -} - -/* This hardwall is gone, so destroy it. */ -static int hardwall_release(struct inode *inode, struct file *file) -{ - hardwall_destroy(file->private_data); - return 0; -} - -static const struct file_operations dev_hardwall_fops = { - .open = nonseekable_open, - .unlocked_ioctl = hardwall_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = hardwall_compat_ioctl, -#endif - .flush = hardwall_flush, - .release = hardwall_release, -}; - -static struct cdev hardwall_dev; - -static int __init dev_hardwall_init(void) -{ - int rc; - dev_t dev; - - rc = alloc_chrdev_region(&dev, 0, HARDWALL_TYPES, "hardwall"); - if (rc < 0) - return rc; - cdev_init(&hardwall_dev, &dev_hardwall_fops); - rc = cdev_add(&hardwall_dev, dev, HARDWALL_TYPES); - if (rc < 0) - return rc; - - return 0; -} -late_initcall(dev_hardwall_init); |
