798 lines
22 KiB
C
798 lines
22 KiB
C
/*
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* Copyright 2010 Tilera Corporation. All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation, version 2.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
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* NON INFRINGEMENT. See the GNU General Public License for
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* more details.
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*/
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#include <linux/fs.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/rwsem.h>
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#include <linux/kprobes.h>
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#include <linux/sched.h>
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#include <linux/hardirq.h>
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#include <linux/uaccess.h>
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#include <linux/smp.h>
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#include <linux/cdev.h>
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#include <linux/compat.h>
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#include <asm/hardwall.h>
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#include <asm/traps.h>
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#include <asm/siginfo.h>
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#include <asm/irq_regs.h>
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#include <arch/interrupts.h>
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#include <arch/spr_def.h>
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/*
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* This data structure tracks the rectangle data, etc., associated
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* one-to-one with a "struct file *" from opening HARDWALL_FILE.
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* Note that the file's private data points back to this structure.
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*/
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struct hardwall_info {
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struct list_head list; /* "rectangles" list */
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struct list_head task_head; /* head of tasks in this hardwall */
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int ulhc_x; /* upper left hand corner x coord */
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int ulhc_y; /* upper left hand corner y coord */
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int width; /* rectangle width */
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int height; /* rectangle height */
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int teardown_in_progress; /* are we tearing this one down? */
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};
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/* Currently allocated hardwall rectangles */
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static LIST_HEAD(rectangles);
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/*
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* Guard changes to the hardwall data structures.
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* This could be finer grained (e.g. one lock for the list of hardwall
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* rectangles, then separate embedded locks for each one's list of tasks),
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* but there are subtle correctness issues when trying to start with
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* a task's "hardwall" pointer and lock the correct rectangle's embedded
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* lock in the presence of a simultaneous deactivation, so it seems
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* easier to have a single lock, given that none of these data
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* structures are touched very frequently during normal operation.
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*/
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static DEFINE_SPINLOCK(hardwall_lock);
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/* Allow disabling UDN access. */
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static int udn_disabled;
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static int __init noudn(char *str)
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{
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pr_info("User-space UDN access is disabled\n");
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udn_disabled = 1;
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return 0;
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}
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early_param("noudn", noudn);
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/*
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* Low-level primitives
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*/
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/* Set a CPU bit if the CPU is online. */
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#define cpu_online_set(cpu, dst) do { \
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if (cpu_online(cpu)) \
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cpumask_set_cpu(cpu, dst); \
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} while (0)
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/* Does the given rectangle contain the given x,y coordinate? */
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static int contains(struct hardwall_info *r, int x, int y)
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{
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return (x >= r->ulhc_x && x < r->ulhc_x + r->width) &&
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(y >= r->ulhc_y && y < r->ulhc_y + r->height);
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}
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/* Compute the rectangle parameters and validate the cpumask. */
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static int setup_rectangle(struct hardwall_info *r, struct cpumask *mask)
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{
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int x, y, cpu, ulhc, lrhc;
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/* The first cpu is the ULHC, the last the LRHC. */
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ulhc = find_first_bit(cpumask_bits(mask), nr_cpumask_bits);
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lrhc = find_last_bit(cpumask_bits(mask), nr_cpumask_bits);
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/* Compute the rectangle attributes from the cpus. */
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r->ulhc_x = cpu_x(ulhc);
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r->ulhc_y = cpu_y(ulhc);
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r->width = cpu_x(lrhc) - r->ulhc_x + 1;
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r->height = cpu_y(lrhc) - r->ulhc_y + 1;
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/* Width and height must be positive */
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if (r->width <= 0 || r->height <= 0)
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return -EINVAL;
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/* Confirm that the cpumask is exactly the rectangle. */
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for (y = 0, cpu = 0; y < smp_height; ++y)
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for (x = 0; x < smp_width; ++x, ++cpu)
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if (cpumask_test_cpu(cpu, mask) != contains(r, x, y))
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return -EINVAL;
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/*
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* Note that offline cpus can't be drained when this UDN
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* rectangle eventually closes. We used to detect this
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* situation and print a warning, but it annoyed users and
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* they ignored it anyway, so now we just return without a
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* warning.
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*/
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return 0;
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}
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/* Do the two given rectangles overlap on any cpu? */
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static int overlaps(struct hardwall_info *a, struct hardwall_info *b)
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{
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return a->ulhc_x + a->width > b->ulhc_x && /* A not to the left */
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b->ulhc_x + b->width > a->ulhc_x && /* B not to the left */
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a->ulhc_y + a->height > b->ulhc_y && /* A not above */
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b->ulhc_y + b->height > a->ulhc_y; /* B not above */
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}
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/*
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* Hardware management of hardwall setup, teardown, trapping,
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* and enabling/disabling PL0 access to the networks.
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*/
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/* Bit field values to mask together for writes to SPR_XDN_DIRECTION_PROTECT */
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enum direction_protect {
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N_PROTECT = (1 << 0),
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E_PROTECT = (1 << 1),
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S_PROTECT = (1 << 2),
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W_PROTECT = (1 << 3)
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};
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static void enable_firewall_interrupts(void)
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{
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arch_local_irq_unmask_now(INT_UDN_FIREWALL);
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}
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static void disable_firewall_interrupts(void)
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{
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arch_local_irq_mask_now(INT_UDN_FIREWALL);
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}
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/* Set up hardwall on this cpu based on the passed hardwall_info. */
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static void hardwall_setup_ipi_func(void *info)
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{
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struct hardwall_info *r = info;
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int cpu = smp_processor_id();
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int x = cpu % smp_width;
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int y = cpu / smp_width;
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int bits = 0;
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if (x == r->ulhc_x)
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bits |= W_PROTECT;
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if (x == r->ulhc_x + r->width - 1)
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bits |= E_PROTECT;
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if (y == r->ulhc_y)
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bits |= N_PROTECT;
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if (y == r->ulhc_y + r->height - 1)
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bits |= S_PROTECT;
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BUG_ON(bits == 0);
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__insn_mtspr(SPR_UDN_DIRECTION_PROTECT, bits);
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enable_firewall_interrupts();
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}
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/* Set up all cpus on edge of rectangle to enable/disable hardwall SPRs. */
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static void hardwall_setup(struct hardwall_info *r)
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{
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int x, y, cpu, delta;
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struct cpumask rect_cpus;
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cpumask_clear(&rect_cpus);
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/* First include the top and bottom edges */
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cpu = r->ulhc_y * smp_width + r->ulhc_x;
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delta = (r->height - 1) * smp_width;
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for (x = 0; x < r->width; ++x, ++cpu) {
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cpu_online_set(cpu, &rect_cpus);
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cpu_online_set(cpu + delta, &rect_cpus);
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}
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/* Then the left and right edges */
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cpu -= r->width;
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delta = r->width - 1;
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for (y = 0; y < r->height; ++y, cpu += smp_width) {
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cpu_online_set(cpu, &rect_cpus);
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cpu_online_set(cpu + delta, &rect_cpus);
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}
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/* Then tell all the cpus to set up their protection SPR */
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on_each_cpu_mask(&rect_cpus, hardwall_setup_ipi_func, r, 1);
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}
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void __kprobes do_hardwall_trap(struct pt_regs* regs, int fault_num)
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{
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struct hardwall_info *rect;
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struct task_struct *p;
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struct siginfo info;
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int x, y;
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int cpu = smp_processor_id();
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int found_processes;
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unsigned long flags;
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struct pt_regs *old_regs = set_irq_regs(regs);
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irq_enter();
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/* This tile trapped a network access; find the rectangle. */
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x = cpu % smp_width;
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y = cpu / smp_width;
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spin_lock_irqsave(&hardwall_lock, flags);
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list_for_each_entry(rect, &rectangles, list) {
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if (contains(rect, x, y))
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break;
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}
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/*
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* It shouldn't be possible not to find this cpu on the
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* rectangle list, since only cpus in rectangles get hardwalled.
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* The hardwall is only removed after the UDN is drained.
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*/
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BUG_ON(&rect->list == &rectangles);
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/*
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* If we already started teardown on this hardwall, don't worry;
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* the abort signal has been sent and we are just waiting for things
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* to quiesce.
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*/
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if (rect->teardown_in_progress) {
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pr_notice("cpu %d: detected hardwall violation %#lx"
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" while teardown already in progress\n",
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cpu, (long) __insn_mfspr(SPR_UDN_DIRECTION_PROTECT));
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goto done;
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}
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/*
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* Kill off any process that is activated in this rectangle.
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* We bypass security to deliver the signal, since it must be
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* one of the activated processes that generated the UDN
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* message that caused this trap, and all the activated
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* processes shared a single open file so are pretty tightly
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* bound together from a security point of view to begin with.
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*/
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rect->teardown_in_progress = 1;
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wmb(); /* Ensure visibility of rectangle before notifying processes. */
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pr_notice("cpu %d: detected hardwall violation %#lx...\n",
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cpu, (long) __insn_mfspr(SPR_UDN_DIRECTION_PROTECT));
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info.si_signo = SIGILL;
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info.si_errno = 0;
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info.si_code = ILL_HARDWALL;
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found_processes = 0;
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list_for_each_entry(p, &rect->task_head, thread.hardwall_list) {
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BUG_ON(p->thread.hardwall != rect);
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if (p->sighand) {
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found_processes = 1;
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pr_notice("hardwall: killing %d\n", p->pid);
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spin_lock(&p->sighand->siglock);
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__group_send_sig_info(info.si_signo, &info, p);
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spin_unlock(&p->sighand->siglock);
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}
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}
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if (!found_processes)
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pr_notice("hardwall: no associated processes!\n");
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done:
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spin_unlock_irqrestore(&hardwall_lock, flags);
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/*
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* We have to disable firewall interrupts now, or else when we
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* return from this handler, we will simply re-interrupt back to
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* it. However, we can't clear the protection bits, since we
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* haven't yet drained the network, and that would allow packets
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* to cross out of the hardwall region.
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*/
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disable_firewall_interrupts();
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irq_exit();
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set_irq_regs(old_regs);
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}
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/* Allow access from user space to the UDN. */
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void grant_network_mpls(void)
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{
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__insn_mtspr(SPR_MPL_UDN_ACCESS_SET_0, 1);
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__insn_mtspr(SPR_MPL_UDN_AVAIL_SET_0, 1);
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__insn_mtspr(SPR_MPL_UDN_COMPLETE_SET_0, 1);
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__insn_mtspr(SPR_MPL_UDN_TIMER_SET_0, 1);
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#if !CHIP_HAS_REV1_XDN()
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__insn_mtspr(SPR_MPL_UDN_REFILL_SET_0, 1);
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__insn_mtspr(SPR_MPL_UDN_CA_SET_0, 1);
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#endif
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}
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/* Deny access from user space to the UDN. */
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void restrict_network_mpls(void)
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{
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__insn_mtspr(SPR_MPL_UDN_ACCESS_SET_1, 1);
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__insn_mtspr(SPR_MPL_UDN_AVAIL_SET_1, 1);
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__insn_mtspr(SPR_MPL_UDN_COMPLETE_SET_1, 1);
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__insn_mtspr(SPR_MPL_UDN_TIMER_SET_1, 1);
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#if !CHIP_HAS_REV1_XDN()
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__insn_mtspr(SPR_MPL_UDN_REFILL_SET_1, 1);
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__insn_mtspr(SPR_MPL_UDN_CA_SET_1, 1);
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#endif
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}
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/*
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* Code to create, activate, deactivate, and destroy hardwall rectangles.
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*/
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/* Create a hardwall for the given rectangle */
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static struct hardwall_info *hardwall_create(
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size_t size, const unsigned char __user *bits)
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{
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struct hardwall_info *iter, *rect;
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struct cpumask mask;
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unsigned long flags;
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int rc;
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/* Reject crazy sizes out of hand, a la sys_mbind(). */
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if (size > PAGE_SIZE)
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return ERR_PTR(-EINVAL);
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/* Copy whatever fits into a cpumask. */
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if (copy_from_user(&mask, bits, min(sizeof(struct cpumask), size)))
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return ERR_PTR(-EFAULT);
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/*
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* If the size was short, clear the rest of the mask;
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* otherwise validate that the rest of the user mask was zero
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* (we don't try hard to be efficient when validating huge masks).
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*/
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if (size < sizeof(struct cpumask)) {
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memset((char *)&mask + size, 0, sizeof(struct cpumask) - size);
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} else if (size > sizeof(struct cpumask)) {
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size_t i;
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for (i = sizeof(struct cpumask); i < size; ++i) {
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char c;
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if (get_user(c, &bits[i]))
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return ERR_PTR(-EFAULT);
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if (c)
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return ERR_PTR(-EINVAL);
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}
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}
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/* Allocate a new rectangle optimistically. */
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rect = kmalloc(sizeof(struct hardwall_info),
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GFP_KERNEL | __GFP_ZERO);
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if (rect == NULL)
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return ERR_PTR(-ENOMEM);
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INIT_LIST_HEAD(&rect->task_head);
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/* Compute the rectangle size and validate that it's plausible. */
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rc = setup_rectangle(rect, &mask);
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if (rc != 0) {
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kfree(rect);
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return ERR_PTR(rc);
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}
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/* Confirm it doesn't overlap and add it to the list. */
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spin_lock_irqsave(&hardwall_lock, flags);
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list_for_each_entry(iter, &rectangles, list) {
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if (overlaps(iter, rect)) {
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spin_unlock_irqrestore(&hardwall_lock, flags);
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kfree(rect);
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return ERR_PTR(-EBUSY);
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}
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}
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list_add_tail(&rect->list, &rectangles);
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spin_unlock_irqrestore(&hardwall_lock, flags);
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/* Set up appropriate hardwalling on all affected cpus. */
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hardwall_setup(rect);
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return rect;
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}
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/* Activate a given hardwall on this cpu for this process. */
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static int hardwall_activate(struct hardwall_info *rect)
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{
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int cpu, x, y;
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unsigned long flags;
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struct task_struct *p = current;
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struct thread_struct *ts = &p->thread;
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/* Require a rectangle. */
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if (rect == NULL)
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return -ENODATA;
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/* Not allowed to activate a rectangle that is being torn down. */
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if (rect->teardown_in_progress)
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return -EINVAL;
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/*
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* Get our affinity; if we're not bound to this tile uniquely,
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* we can't access the network registers.
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*/
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if (cpumask_weight(&p->cpus_allowed) != 1)
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return -EPERM;
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/* Make sure we are bound to a cpu in this rectangle. */
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cpu = smp_processor_id();
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BUG_ON(cpumask_first(&p->cpus_allowed) != cpu);
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x = cpu_x(cpu);
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y = cpu_y(cpu);
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if (!contains(rect, x, y))
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return -EINVAL;
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/* If we are already bound to this hardwall, it's a no-op. */
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if (ts->hardwall) {
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BUG_ON(ts->hardwall != rect);
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return 0;
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}
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/* Success! This process gets to use the user networks on this cpu. */
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ts->hardwall = rect;
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spin_lock_irqsave(&hardwall_lock, flags);
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list_add(&ts->hardwall_list, &rect->task_head);
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spin_unlock_irqrestore(&hardwall_lock, flags);
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grant_network_mpls();
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printk(KERN_DEBUG "Pid %d (%s) activated for hardwall: cpu %d\n",
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p->pid, p->comm, cpu);
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return 0;
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}
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/*
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* Deactivate a task's hardwall. Must hold hardwall_lock.
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* This method may be called from free_task(), so we don't want to
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* rely on too many fields of struct task_struct still being valid.
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* We assume the cpus_allowed, pid, and comm fields are still valid.
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*/
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static void _hardwall_deactivate(struct task_struct *task)
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{
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struct thread_struct *ts = &task->thread;
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if (cpumask_weight(&task->cpus_allowed) != 1) {
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pr_err("pid %d (%s) releasing networks with"
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" an affinity mask containing %d cpus!\n",
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task->pid, task->comm,
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cpumask_weight(&task->cpus_allowed));
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BUG();
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}
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BUG_ON(ts->hardwall == NULL);
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ts->hardwall = NULL;
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list_del(&ts->hardwall_list);
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if (task == current)
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restrict_network_mpls();
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}
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/* Deactivate a task's hardwall. */
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int hardwall_deactivate(struct task_struct *task)
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{
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unsigned long flags;
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int activated;
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spin_lock_irqsave(&hardwall_lock, flags);
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activated = (task->thread.hardwall != NULL);
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if (activated)
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_hardwall_deactivate(task);
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spin_unlock_irqrestore(&hardwall_lock, flags);
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if (!activated)
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return -EINVAL;
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printk(KERN_DEBUG "Pid %d (%s) deactivated for hardwall: cpu %d\n",
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task->pid, task->comm, smp_processor_id());
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return 0;
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}
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/* Stop a UDN switch before draining the network. */
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static void stop_udn_switch(void *ignored)
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{
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#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);
|
|
#endif
|
|
}
|
|
|
|
/* Drain all the state from a stopped switch. */
|
|
static void drain_udn_switch(void *ignored)
|
|
{
|
|
#if !CHIP_HAS_REV1_XDN()
|
|
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. */
|
|
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();
|
|
BUG_ON((__insn_mfspr(SPR_UDN_DATA_AVAIL) & 0xF) != 0);
|
|
|
|
/* 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 UDN state registers at boot up and during hardwall teardown. */
|
|
void reset_network_state(void)
|
|
{
|
|
#if !CHIP_HAS_REV1_XDN()
|
|
/* Reset UDN coordinates to their standard value */
|
|
unsigned int cpu = smp_processor_id();
|
|
unsigned int x = cpu % smp_width;
|
|
unsigned int y = cpu / smp_width;
|
|
#endif
|
|
|
|
if (udn_disabled)
|
|
return;
|
|
|
|
#if !CHIP_HAS_REV1_XDN()
|
|
__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));
|
|
#endif
|
|
|
|
/* Clear out other random registers so we have a clean slate. */
|
|
__insn_mtspr(SPR_UDN_AVAIL_EN, 0);
|
|
__insn_mtspr(SPR_UDN_DEADLOCK_TIMEOUT, 0);
|
|
#if !CHIP_HAS_REV1_XDN()
|
|
__insn_mtspr(SPR_UDN_REFILL_EN, 0);
|
|
__insn_mtspr(SPR_UDN_DEMUX_QUEUE_SEL, 0);
|
|
__insn_mtspr(SPR_UDN_SP_FIFO_SEL, 0);
|
|
#endif
|
|
|
|
/* Start the switch and demux. */
|
|
#if !CHIP_HAS_REV1_XDN()
|
|
__insn_mtspr(SPR_UDN_SP_FREEZE, 0);
|
|
#endif
|
|
}
|
|
|
|
/* Restart a UDN switch after draining. */
|
|
static void restart_udn_switch(void *ignored)
|
|
{
|
|
reset_network_state();
|
|
|
|
/* Disable firewall interrupts. */
|
|
__insn_mtspr(SPR_UDN_DIRECTION_PROTECT, 0);
|
|
disable_firewall_interrupts();
|
|
}
|
|
|
|
/* Build a struct cpumask containing all valid tiles in bounding rectangle. */
|
|
static void fill_mask(struct hardwall_info *r, struct cpumask *result)
|
|
{
|
|
int x, y, cpu;
|
|
|
|
cpumask_clear(result);
|
|
|
|
cpu = r->ulhc_y * smp_width + r->ulhc_x;
|
|
for (y = 0; y < r->height; ++y, cpu += smp_width - r->width) {
|
|
for (x = 0; x < r->width; ++x, ++cpu)
|
|
cpu_online_set(cpu, result);
|
|
}
|
|
}
|
|
|
|
/* Last reference to a hardwall is gone, so clear the network. */
|
|
static void hardwall_destroy(struct hardwall_info *rect)
|
|
{
|
|
struct task_struct *task;
|
|
unsigned long flags;
|
|
struct cpumask mask;
|
|
|
|
/* Make sure this file actually represents a rectangle. */
|
|
if (rect == 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.
|
|
*/
|
|
spin_lock_irqsave(&hardwall_lock, flags);
|
|
list_for_each_entry(task, &rect->task_head, thread.hardwall_list)
|
|
_hardwall_deactivate(task);
|
|
spin_unlock_irqrestore(&hardwall_lock, flags);
|
|
|
|
/* Drain the UDN. */
|
|
printk(KERN_DEBUG "Clearing hardwall rectangle %dx%d %d,%d\n",
|
|
rect->width, rect->height, rect->ulhc_x, rect->ulhc_y);
|
|
fill_mask(rect, &mask);
|
|
on_each_cpu_mask(&mask, stop_udn_switch, NULL, 1);
|
|
on_each_cpu_mask(&mask, drain_udn_switch, NULL, 1);
|
|
|
|
/* Restart switch and disable firewall. */
|
|
on_each_cpu_mask(&mask, restart_udn_switch, NULL, 1);
|
|
|
|
/* Now free the rectangle from the list. */
|
|
spin_lock_irqsave(&hardwall_lock, flags);
|
|
BUG_ON(!list_empty(&rect->task_head));
|
|
list_del(&rect->list);
|
|
spin_unlock_irqrestore(&hardwall_lock, flags);
|
|
kfree(rect);
|
|
}
|
|
|
|
|
|
/*
|
|
* Dump hardwall state via /proc; initialized in arch/tile/sys/proc.c.
|
|
*/
|
|
int proc_tile_hardwall_show(struct seq_file *sf, void *v)
|
|
{
|
|
struct hardwall_info *r;
|
|
|
|
if (udn_disabled) {
|
|
seq_printf(sf, "%dx%d 0,0 pids:\n", smp_width, smp_height);
|
|
return 0;
|
|
}
|
|
|
|
spin_lock_irq(&hardwall_lock);
|
|
list_for_each_entry(r, &rectangles, list) {
|
|
struct task_struct *p;
|
|
seq_printf(sf, "%dx%d %d,%d pids:",
|
|
r->width, r->height, r->ulhc_x, r->ulhc_y);
|
|
list_for_each_entry(p, &r->task_head, thread.hardwall_list) {
|
|
unsigned int cpu = cpumask_first(&p->cpus_allowed);
|
|
unsigned int x = cpu % smp_width;
|
|
unsigned int y = cpu / smp_width;
|
|
seq_printf(sf, " %d@%d,%d", p->pid, x, y);
|
|
}
|
|
seq_printf(sf, "\n");
|
|
}
|
|
spin_unlock_irq(&hardwall_lock);
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* Character device support via ioctl/close.
|
|
*/
|
|
|
|
static long hardwall_ioctl(struct file *file, unsigned int a, unsigned long b)
|
|
{
|
|
struct hardwall_info *rect = file->private_data;
|
|
|
|
if (_IOC_TYPE(a) != HARDWALL_IOCTL_BASE)
|
|
return -EINVAL;
|
|
|
|
switch (_IOC_NR(a)) {
|
|
case _HARDWALL_CREATE:
|
|
if (udn_disabled)
|
|
return -ENOSYS;
|
|
if (rect != NULL)
|
|
return -EALREADY;
|
|
rect = hardwall_create(_IOC_SIZE(a),
|
|
(const unsigned char __user *)b);
|
|
if (IS_ERR(rect))
|
|
return PTR_ERR(rect);
|
|
file->private_data = rect;
|
|
return 0;
|
|
|
|
case _HARDWALL_ACTIVATE:
|
|
return hardwall_activate(rect);
|
|
|
|
case _HARDWALL_DEACTIVATE:
|
|
if (current->thread.hardwall != rect)
|
|
return -EINVAL;
|
|
return hardwall_deactivate(current);
|
|
|
|
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 *rect = file->private_data;
|
|
struct task_struct *task, *tmp;
|
|
unsigned long flags;
|
|
|
|
if (rect) {
|
|
/*
|
|
* NOTE: if multiple threads are activated on this hardwall
|
|
* file, the other threads will continue having access to the
|
|
* UDN 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.
|
|
*/
|
|
spin_lock_irqsave(&hardwall_lock, flags);
|
|
list_for_each_entry_safe(task, tmp, &rect->task_head,
|
|
thread.hardwall_list) {
|
|
if (task->files == owner || task->files == NULL)
|
|
_hardwall_deactivate(task);
|
|
}
|
|
spin_unlock_irqrestore(&hardwall_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, 1, "hardwall");
|
|
if (rc < 0)
|
|
return rc;
|
|
cdev_init(&hardwall_dev, &dev_hardwall_fops);
|
|
rc = cdev_add(&hardwall_dev, dev, 1);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
return 0;
|
|
}
|
|
late_initcall(dev_hardwall_init);
|