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1923 lines
48 KiB
1923 lines
48 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* linux/kernel/resource.c |
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* |
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* Copyright (C) 1999 Linus Torvalds |
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* Copyright (C) 1999 Martin Mares <[email protected]> |
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* |
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* Arbitrary resource management. |
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*/ |
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|
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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|
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#include <linux/export.h> |
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#include <linux/errno.h> |
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#include <linux/ioport.h> |
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#include <linux/init.h> |
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#include <linux/slab.h> |
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#include <linux/spinlock.h> |
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#include <linux/fs.h> |
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#include <linux/proc_fs.h> |
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#include <linux/pseudo_fs.h> |
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#include <linux/sched.h> |
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#include <linux/seq_file.h> |
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#include <linux/device.h> |
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#include <linux/pfn.h> |
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#include <linux/mm.h> |
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#include <linux/mount.h> |
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#include <linux/resource_ext.h> |
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#include <uapi/linux/magic.h> |
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#include <asm/io.h> |
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struct resource ioport_resource = { |
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.name = "PCI IO", |
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.start = 0, |
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.end = IO_SPACE_LIMIT, |
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.flags = IORESOURCE_IO, |
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}; |
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EXPORT_SYMBOL(ioport_resource); |
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struct resource iomem_resource = { |
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.name = "PCI mem", |
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.start = 0, |
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.end = -1, |
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.flags = IORESOURCE_MEM, |
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}; |
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EXPORT_SYMBOL(iomem_resource); |
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|
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/* constraints to be met while allocating resources */ |
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struct resource_constraint { |
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resource_size_t min, max, align; |
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resource_size_t (*alignf)(void *, const struct resource *, |
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resource_size_t, resource_size_t); |
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void *alignf_data; |
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}; |
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static DEFINE_RWLOCK(resource_lock); |
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|
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/* |
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* For memory hotplug, there is no way to free resource entries allocated |
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* by boot mem after the system is up. So for reusing the resource entry |
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* we need to remember the resource. |
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*/ |
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static struct resource *bootmem_resource_free; |
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static DEFINE_SPINLOCK(bootmem_resource_lock); |
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static struct resource *next_resource(struct resource *p) |
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{ |
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if (p->child) |
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return p->child; |
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while (!p->sibling && p->parent) |
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p = p->parent; |
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return p->sibling; |
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} |
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static void *r_next(struct seq_file *m, void *v, loff_t *pos) |
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{ |
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struct resource *p = v; |
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(*pos)++; |
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return (void *)next_resource(p); |
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} |
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#ifdef CONFIG_PROC_FS |
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enum { MAX_IORES_LEVEL = 5 }; |
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static void *r_start(struct seq_file *m, loff_t *pos) |
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__acquires(resource_lock) |
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{ |
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struct resource *p = PDE_DATA(file_inode(m->file)); |
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loff_t l = 0; |
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read_lock(&resource_lock); |
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for (p = p->child; p && l < *pos; p = r_next(m, p, &l)) |
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; |
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return p; |
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} |
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static void r_stop(struct seq_file *m, void *v) |
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__releases(resource_lock) |
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{ |
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read_unlock(&resource_lock); |
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} |
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static int r_show(struct seq_file *m, void *v) |
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{ |
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struct resource *root = PDE_DATA(file_inode(m->file)); |
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struct resource *r = v, *p; |
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unsigned long long start, end; |
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int width = root->end < 0x10000 ? 4 : 8; |
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int depth; |
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for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent) |
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if (p->parent == root) |
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break; |
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if (file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN)) { |
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start = r->start; |
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end = r->end; |
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} else { |
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start = end = 0; |
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} |
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seq_printf(m, "%*s%0*llx-%0*llx : %s\n", |
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depth * 2, "", |
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width, start, |
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width, end, |
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r->name ? r->name : "<BAD>"); |
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return 0; |
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} |
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static const struct seq_operations resource_op = { |
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.start = r_start, |
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.next = r_next, |
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.stop = r_stop, |
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.show = r_show, |
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}; |
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static int __init ioresources_init(void) |
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{ |
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proc_create_seq_data("ioports", 0, NULL, &resource_op, |
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&ioport_resource); |
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proc_create_seq_data("iomem", 0, NULL, &resource_op, &iomem_resource); |
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return 0; |
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} |
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__initcall(ioresources_init); |
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#endif /* CONFIG_PROC_FS */ |
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static void free_resource(struct resource *res) |
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{ |
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if (!res) |
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return; |
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if (!PageSlab(virt_to_head_page(res))) { |
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spin_lock(&bootmem_resource_lock); |
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res->sibling = bootmem_resource_free; |
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bootmem_resource_free = res; |
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spin_unlock(&bootmem_resource_lock); |
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} else { |
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kfree(res); |
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} |
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} |
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static struct resource *alloc_resource(gfp_t flags) |
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{ |
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struct resource *res = NULL; |
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spin_lock(&bootmem_resource_lock); |
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if (bootmem_resource_free) { |
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res = bootmem_resource_free; |
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bootmem_resource_free = res->sibling; |
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} |
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spin_unlock(&bootmem_resource_lock); |
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if (res) |
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memset(res, 0, sizeof(struct resource)); |
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else |
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res = kzalloc(sizeof(struct resource), flags); |
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return res; |
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} |
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/* Return the conflict entry if you can't request it */ |
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static struct resource * __request_resource(struct resource *root, struct resource *new) |
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{ |
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resource_size_t start = new->start; |
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resource_size_t end = new->end; |
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struct resource *tmp, **p; |
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if (end < start) |
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return root; |
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if (start < root->start) |
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return root; |
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if (end > root->end) |
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return root; |
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p = &root->child; |
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for (;;) { |
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tmp = *p; |
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if (!tmp || tmp->start > end) { |
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new->sibling = tmp; |
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*p = new; |
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new->parent = root; |
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return NULL; |
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} |
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p = &tmp->sibling; |
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if (tmp->end < start) |
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continue; |
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return tmp; |
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} |
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} |
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static int __release_resource(struct resource *old, bool release_child) |
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{ |
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struct resource *tmp, **p, *chd; |
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|
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if (!old->parent) { |
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WARN(old->sibling, "sibling but no parent"); |
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if (old->sibling) |
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return -EINVAL; |
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return 0; |
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} |
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p = &old->parent->child; |
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for (;;) { |
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tmp = *p; |
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if (!tmp) |
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break; |
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if (tmp == old) { |
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if (release_child || !(tmp->child)) { |
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*p = tmp->sibling; |
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} else { |
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for (chd = tmp->child;; chd = chd->sibling) { |
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chd->parent = tmp->parent; |
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if (!(chd->sibling)) |
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break; |
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} |
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*p = tmp->child; |
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chd->sibling = tmp->sibling; |
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} |
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old->parent = NULL; |
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return 0; |
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} |
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p = &tmp->sibling; |
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} |
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return -EINVAL; |
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} |
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static void __release_child_resources(struct resource *r) |
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{ |
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struct resource *tmp, *p; |
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resource_size_t size; |
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p = r->child; |
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r->child = NULL; |
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while (p) { |
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tmp = p; |
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p = p->sibling; |
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tmp->parent = NULL; |
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tmp->sibling = NULL; |
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__release_child_resources(tmp); |
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printk(KERN_DEBUG "release child resource %pR\n", tmp); |
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/* need to restore size, and keep flags */ |
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size = resource_size(tmp); |
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tmp->start = 0; |
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tmp->end = size - 1; |
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} |
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} |
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void release_child_resources(struct resource *r) |
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{ |
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write_lock(&resource_lock); |
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__release_child_resources(r); |
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write_unlock(&resource_lock); |
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} |
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/** |
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* request_resource_conflict - request and reserve an I/O or memory resource |
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* @root: root resource descriptor |
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* @new: resource descriptor desired by caller |
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* |
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* Returns 0 for success, conflict resource on error. |
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*/ |
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struct resource *request_resource_conflict(struct resource *root, struct resource *new) |
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{ |
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struct resource *conflict; |
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write_lock(&resource_lock); |
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conflict = __request_resource(root, new); |
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write_unlock(&resource_lock); |
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return conflict; |
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} |
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/** |
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* request_resource - request and reserve an I/O or memory resource |
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* @root: root resource descriptor |
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* @new: resource descriptor desired by caller |
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* |
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* Returns 0 for success, negative error code on error. |
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*/ |
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int request_resource(struct resource *root, struct resource *new) |
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{ |
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struct resource *conflict; |
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conflict = request_resource_conflict(root, new); |
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return conflict ? -EBUSY : 0; |
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} |
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EXPORT_SYMBOL(request_resource); |
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/** |
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* release_resource - release a previously reserved resource |
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* @old: resource pointer |
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*/ |
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int release_resource(struct resource *old) |
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{ |
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int retval; |
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write_lock(&resource_lock); |
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retval = __release_resource(old, true); |
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write_unlock(&resource_lock); |
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return retval; |
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} |
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EXPORT_SYMBOL(release_resource); |
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|
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/** |
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* find_next_iomem_res - Finds the lowest iomem resource that covers part of |
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* [@start..@end]. |
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* |
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* If a resource is found, returns 0 and @*res is overwritten with the part |
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* of the resource that's within [@start..@end]; if none is found, returns |
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* -ENODEV. Returns -EINVAL for invalid parameters. |
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* |
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* @start: start address of the resource searched for |
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* @end: end address of same resource |
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* @flags: flags which the resource must have |
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* @desc: descriptor the resource must have |
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* @res: return ptr, if resource found |
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* |
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* The caller must specify @start, @end, @flags, and @desc |
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* (which may be IORES_DESC_NONE). |
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*/ |
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static int find_next_iomem_res(resource_size_t start, resource_size_t end, |
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unsigned long flags, unsigned long desc, |
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struct resource *res) |
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{ |
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struct resource *p; |
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if (!res) |
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return -EINVAL; |
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if (start >= end) |
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return -EINVAL; |
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read_lock(&resource_lock); |
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for (p = iomem_resource.child; p; p = next_resource(p)) { |
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/* If we passed the resource we are looking for, stop */ |
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if (p->start > end) { |
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p = NULL; |
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break; |
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} |
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/* Skip until we find a range that matches what we look for */ |
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if (p->end < start) |
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continue; |
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if ((p->flags & flags) != flags) |
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continue; |
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if ((desc != IORES_DESC_NONE) && (desc != p->desc)) |
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continue; |
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/* Found a match, break */ |
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break; |
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} |
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if (p) { |
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/* copy data */ |
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*res = (struct resource) { |
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.start = max(start, p->start), |
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.end = min(end, p->end), |
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.flags = p->flags, |
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.desc = p->desc, |
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.parent = p->parent, |
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}; |
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} |
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read_unlock(&resource_lock); |
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return p ? 0 : -ENODEV; |
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} |
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static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end, |
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unsigned long flags, unsigned long desc, |
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void *arg, |
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int (*func)(struct resource *, void *)) |
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{ |
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struct resource res; |
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int ret = -EINVAL; |
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while (start < end && |
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!find_next_iomem_res(start, end, flags, desc, &res)) { |
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ret = (*func)(&res, arg); |
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if (ret) |
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break; |
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start = res.end + 1; |
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} |
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return ret; |
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} |
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/** |
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* walk_iomem_res_desc - Walks through iomem resources and calls func() |
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* with matching resource ranges. |
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* * |
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* @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check. |
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* @flags: I/O resource flags |
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* @start: start addr |
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* @end: end addr |
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* @arg: function argument for the callback @func |
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* @func: callback function that is called for each qualifying resource area |
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* |
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* All the memory ranges which overlap start,end and also match flags and |
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* desc are valid candidates. |
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* |
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* NOTE: For a new descriptor search, define a new IORES_DESC in |
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* <linux/ioport.h> and set it in 'desc' of a target resource entry. |
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*/ |
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int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start, |
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u64 end, void *arg, int (*func)(struct resource *, void *)) |
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{ |
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return __walk_iomem_res_desc(start, end, flags, desc, arg, func); |
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} |
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EXPORT_SYMBOL_GPL(walk_iomem_res_desc); |
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|
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/* |
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* This function calls the @func callback against all memory ranges of type |
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* System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. |
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* Now, this function is only for System RAM, it deals with full ranges and |
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* not PFNs. If resources are not PFN-aligned, dealing with PFNs can truncate |
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* ranges. |
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*/ |
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int walk_system_ram_res(u64 start, u64 end, void *arg, |
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int (*func)(struct resource *, void *)) |
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{ |
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unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; |
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return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, arg, |
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func); |
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} |
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|
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/* |
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* This function calls the @func callback against all memory ranges, which |
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* are ranges marked as IORESOURCE_MEM and IORESOUCE_BUSY. |
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*/ |
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int walk_mem_res(u64 start, u64 end, void *arg, |
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int (*func)(struct resource *, void *)) |
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{ |
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unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
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return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, arg, |
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func); |
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} |
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|
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/* |
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* This function calls the @func callback against all memory ranges of type |
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* System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. |
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* It is to be used only for System RAM. |
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*/ |
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int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, |
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void *arg, int (*func)(unsigned long, unsigned long, void *)) |
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{ |
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resource_size_t start, end; |
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unsigned long flags; |
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struct resource res; |
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unsigned long pfn, end_pfn; |
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int ret = -EINVAL; |
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start = (u64) start_pfn << PAGE_SHIFT; |
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end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; |
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flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; |
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while (start < end && |
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!find_next_iomem_res(start, end, flags, IORES_DESC_NONE, &res)) { |
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pfn = PFN_UP(res.start); |
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end_pfn = PFN_DOWN(res.end + 1); |
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if (end_pfn > pfn) |
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ret = (*func)(pfn, end_pfn - pfn, arg); |
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if (ret) |
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break; |
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start = res.end + 1; |
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} |
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return ret; |
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} |
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|
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static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg) |
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{ |
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return 1; |
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} |
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|
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/* |
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* This generic page_is_ram() returns true if specified address is |
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* registered as System RAM in iomem_resource list. |
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*/ |
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int __weak page_is_ram(unsigned long pfn) |
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{ |
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return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1; |
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} |
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EXPORT_SYMBOL_GPL(page_is_ram); |
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|
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static int __region_intersects(resource_size_t start, size_t size, |
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unsigned long flags, unsigned long desc) |
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{ |
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struct resource res; |
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int type = 0; int other = 0; |
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struct resource *p; |
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|
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res.start = start; |
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res.end = start + size - 1; |
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|
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for (p = iomem_resource.child; p ; p = p->sibling) { |
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bool is_type = (((p->flags & flags) == flags) && |
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((desc == IORES_DESC_NONE) || |
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(desc == p->desc))); |
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|
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if (resource_overlaps(p, &res)) |
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is_type ? type++ : other++; |
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} |
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|
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if (type == 0) |
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return REGION_DISJOINT; |
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|
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if (other == 0) |
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return REGION_INTERSECTS; |
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|
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return REGION_MIXED; |
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} |
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|
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/** |
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* region_intersects() - determine intersection of region with known resources |
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* @start: region start address |
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* @size: size of region |
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* @flags: flags of resource (in iomem_resource) |
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* @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE |
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* |
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* Check if the specified region partially overlaps or fully eclipses a |
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* resource identified by @flags and @desc (optional with IORES_DESC_NONE). |
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* Return REGION_DISJOINT if the region does not overlap @flags/@desc, |
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* return REGION_MIXED if the region overlaps @flags/@desc and another |
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* resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc |
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* and no other defined resource. Note that REGION_INTERSECTS is also |
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* returned in the case when the specified region overlaps RAM and undefined |
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* memory holes. |
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* |
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* region_intersect() is used by memory remapping functions to ensure |
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* the user is not remapping RAM and is a vast speed up over walking |
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* through the resource table page by page. |
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*/ |
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int region_intersects(resource_size_t start, size_t size, unsigned long flags, |
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unsigned long desc) |
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{ |
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int ret; |
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|
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read_lock(&resource_lock); |
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ret = __region_intersects(start, size, flags, desc); |
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read_unlock(&resource_lock); |
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|
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return ret; |
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} |
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EXPORT_SYMBOL_GPL(region_intersects); |
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|
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void __weak arch_remove_reservations(struct resource *avail) |
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{ |
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} |
|
|
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static resource_size_t simple_align_resource(void *data, |
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const struct resource *avail, |
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resource_size_t size, |
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resource_size_t align) |
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{ |
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return avail->start; |
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} |
|
|
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static void resource_clip(struct resource *res, resource_size_t min, |
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resource_size_t max) |
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{ |
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if (res->start < min) |
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res->start = min; |
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if (res->end > max) |
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res->end = max; |
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} |
|
|
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/* |
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* Find empty slot in the resource tree with the given range and |
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* alignment constraints |
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*/ |
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static int __find_resource(struct resource *root, struct resource *old, |
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struct resource *new, |
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resource_size_t size, |
|
struct resource_constraint *constraint) |
|
{ |
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struct resource *this = root->child; |
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struct resource tmp = *new, avail, alloc; |
|
|
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tmp.start = root->start; |
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/* |
|
* Skip past an allocated resource that starts at 0, since the assignment |
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* of this->start - 1 to tmp->end below would cause an underflow. |
|
*/ |
|
if (this && this->start == root->start) { |
|
tmp.start = (this == old) ? old->start : this->end + 1; |
|
this = this->sibling; |
|
} |
|
for(;;) { |
|
if (this) |
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tmp.end = (this == old) ? this->end : this->start - 1; |
|
else |
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tmp.end = root->end; |
|
|
|
if (tmp.end < tmp.start) |
|
goto next; |
|
|
|
resource_clip(&tmp, constraint->min, constraint->max); |
|
arch_remove_reservations(&tmp); |
|
|
|
/* Check for overflow after ALIGN() */ |
|
avail.start = ALIGN(tmp.start, constraint->align); |
|
avail.end = tmp.end; |
|
avail.flags = new->flags & ~IORESOURCE_UNSET; |
|
if (avail.start >= tmp.start) { |
|
alloc.flags = avail.flags; |
|
alloc.start = constraint->alignf(constraint->alignf_data, &avail, |
|
size, constraint->align); |
|
alloc.end = alloc.start + size - 1; |
|
if (alloc.start <= alloc.end && |
|
resource_contains(&avail, &alloc)) { |
|
new->start = alloc.start; |
|
new->end = alloc.end; |
|
return 0; |
|
} |
|
} |
|
|
|
next: if (!this || this->end == root->end) |
|
break; |
|
|
|
if (this != old) |
|
tmp.start = this->end + 1; |
|
this = this->sibling; |
|
} |
|
return -EBUSY; |
|
} |
|
|
|
/* |
|
* Find empty slot in the resource tree given range and alignment. |
|
*/ |
|
static int find_resource(struct resource *root, struct resource *new, |
|
resource_size_t size, |
|
struct resource_constraint *constraint) |
|
{ |
|
return __find_resource(root, NULL, new, size, constraint); |
|
} |
|
|
|
/** |
|
* reallocate_resource - allocate a slot in the resource tree given range & alignment. |
|
* The resource will be relocated if the new size cannot be reallocated in the |
|
* current location. |
|
* |
|
* @root: root resource descriptor |
|
* @old: resource descriptor desired by caller |
|
* @newsize: new size of the resource descriptor |
|
* @constraint: the size and alignment constraints to be met. |
|
*/ |
|
static int reallocate_resource(struct resource *root, struct resource *old, |
|
resource_size_t newsize, |
|
struct resource_constraint *constraint) |
|
{ |
|
int err=0; |
|
struct resource new = *old; |
|
struct resource *conflict; |
|
|
|
write_lock(&resource_lock); |
|
|
|
if ((err = __find_resource(root, old, &new, newsize, constraint))) |
|
goto out; |
|
|
|
if (resource_contains(&new, old)) { |
|
old->start = new.start; |
|
old->end = new.end; |
|
goto out; |
|
} |
|
|
|
if (old->child) { |
|
err = -EBUSY; |
|
goto out; |
|
} |
|
|
|
if (resource_contains(old, &new)) { |
|
old->start = new.start; |
|
old->end = new.end; |
|
} else { |
|
__release_resource(old, true); |
|
*old = new; |
|
conflict = __request_resource(root, old); |
|
BUG_ON(conflict); |
|
} |
|
out: |
|
write_unlock(&resource_lock); |
|
return err; |
|
} |
|
|
|
|
|
/** |
|
* allocate_resource - allocate empty slot in the resource tree given range & alignment. |
|
* The resource will be reallocated with a new size if it was already allocated |
|
* @root: root resource descriptor |
|
* @new: resource descriptor desired by caller |
|
* @size: requested resource region size |
|
* @min: minimum boundary to allocate |
|
* @max: maximum boundary to allocate |
|
* @align: alignment requested, in bytes |
|
* @alignf: alignment function, optional, called if not NULL |
|
* @alignf_data: arbitrary data to pass to the @alignf function |
|
*/ |
|
int allocate_resource(struct resource *root, struct resource *new, |
|
resource_size_t size, resource_size_t min, |
|
resource_size_t max, resource_size_t align, |
|
resource_size_t (*alignf)(void *, |
|
const struct resource *, |
|
resource_size_t, |
|
resource_size_t), |
|
void *alignf_data) |
|
{ |
|
int err; |
|
struct resource_constraint constraint; |
|
|
|
if (!alignf) |
|
alignf = simple_align_resource; |
|
|
|
constraint.min = min; |
|
constraint.max = max; |
|
constraint.align = align; |
|
constraint.alignf = alignf; |
|
constraint.alignf_data = alignf_data; |
|
|
|
if ( new->parent ) { |
|
/* resource is already allocated, try reallocating with |
|
the new constraints */ |
|
return reallocate_resource(root, new, size, &constraint); |
|
} |
|
|
|
write_lock(&resource_lock); |
|
err = find_resource(root, new, size, &constraint); |
|
if (err >= 0 && __request_resource(root, new)) |
|
err = -EBUSY; |
|
write_unlock(&resource_lock); |
|
return err; |
|
} |
|
|
|
EXPORT_SYMBOL(allocate_resource); |
|
|
|
/** |
|
* lookup_resource - find an existing resource by a resource start address |
|
* @root: root resource descriptor |
|
* @start: resource start address |
|
* |
|
* Returns a pointer to the resource if found, NULL otherwise |
|
*/ |
|
struct resource *lookup_resource(struct resource *root, resource_size_t start) |
|
{ |
|
struct resource *res; |
|
|
|
read_lock(&resource_lock); |
|
for (res = root->child; res; res = res->sibling) { |
|
if (res->start == start) |
|
break; |
|
} |
|
read_unlock(&resource_lock); |
|
|
|
return res; |
|
} |
|
|
|
/* |
|
* Insert a resource into the resource tree. If successful, return NULL, |
|
* otherwise return the conflicting resource (compare to __request_resource()) |
|
*/ |
|
static struct resource * __insert_resource(struct resource *parent, struct resource *new) |
|
{ |
|
struct resource *first, *next; |
|
|
|
for (;; parent = first) { |
|
first = __request_resource(parent, new); |
|
if (!first) |
|
return first; |
|
|
|
if (first == parent) |
|
return first; |
|
if (WARN_ON(first == new)) /* duplicated insertion */ |
|
return first; |
|
|
|
if ((first->start > new->start) || (first->end < new->end)) |
|
break; |
|
if ((first->start == new->start) && (first->end == new->end)) |
|
break; |
|
} |
|
|
|
for (next = first; ; next = next->sibling) { |
|
/* Partial overlap? Bad, and unfixable */ |
|
if (next->start < new->start || next->end > new->end) |
|
return next; |
|
if (!next->sibling) |
|
break; |
|
if (next->sibling->start > new->end) |
|
break; |
|
} |
|
|
|
new->parent = parent; |
|
new->sibling = next->sibling; |
|
new->child = first; |
|
|
|
next->sibling = NULL; |
|
for (next = first; next; next = next->sibling) |
|
next->parent = new; |
|
|
|
if (parent->child == first) { |
|
parent->child = new; |
|
} else { |
|
next = parent->child; |
|
while (next->sibling != first) |
|
next = next->sibling; |
|
next->sibling = new; |
|
} |
|
return NULL; |
|
} |
|
|
|
/** |
|
* insert_resource_conflict - Inserts resource in the resource tree |
|
* @parent: parent of the new resource |
|
* @new: new resource to insert |
|
* |
|
* Returns 0 on success, conflict resource if the resource can't be inserted. |
|
* |
|
* This function is equivalent to request_resource_conflict when no conflict |
|
* happens. If a conflict happens, and the conflicting resources |
|
* entirely fit within the range of the new resource, then the new |
|
* resource is inserted and the conflicting resources become children of |
|
* the new resource. |
|
* |
|
* This function is intended for producers of resources, such as FW modules |
|
* and bus drivers. |
|
*/ |
|
struct resource *insert_resource_conflict(struct resource *parent, struct resource *new) |
|
{ |
|
struct resource *conflict; |
|
|
|
write_lock(&resource_lock); |
|
conflict = __insert_resource(parent, new); |
|
write_unlock(&resource_lock); |
|
return conflict; |
|
} |
|
|
|
/** |
|
* insert_resource - Inserts a resource in the resource tree |
|
* @parent: parent of the new resource |
|
* @new: new resource to insert |
|
* |
|
* Returns 0 on success, -EBUSY if the resource can't be inserted. |
|
* |
|
* This function is intended for producers of resources, such as FW modules |
|
* and bus drivers. |
|
*/ |
|
int insert_resource(struct resource *parent, struct resource *new) |
|
{ |
|
struct resource *conflict; |
|
|
|
conflict = insert_resource_conflict(parent, new); |
|
return conflict ? -EBUSY : 0; |
|
} |
|
EXPORT_SYMBOL_GPL(insert_resource); |
|
|
|
/** |
|
* insert_resource_expand_to_fit - Insert a resource into the resource tree |
|
* @root: root resource descriptor |
|
* @new: new resource to insert |
|
* |
|
* Insert a resource into the resource tree, possibly expanding it in order |
|
* to make it encompass any conflicting resources. |
|
*/ |
|
void insert_resource_expand_to_fit(struct resource *root, struct resource *new) |
|
{ |
|
if (new->parent) |
|
return; |
|
|
|
write_lock(&resource_lock); |
|
for (;;) { |
|
struct resource *conflict; |
|
|
|
conflict = __insert_resource(root, new); |
|
if (!conflict) |
|
break; |
|
if (conflict == root) |
|
break; |
|
|
|
/* Ok, expand resource to cover the conflict, then try again .. */ |
|
if (conflict->start < new->start) |
|
new->start = conflict->start; |
|
if (conflict->end > new->end) |
|
new->end = conflict->end; |
|
|
|
printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name); |
|
} |
|
write_unlock(&resource_lock); |
|
} |
|
|
|
/** |
|
* remove_resource - Remove a resource in the resource tree |
|
* @old: resource to remove |
|
* |
|
* Returns 0 on success, -EINVAL if the resource is not valid. |
|
* |
|
* This function removes a resource previously inserted by insert_resource() |
|
* or insert_resource_conflict(), and moves the children (if any) up to |
|
* where they were before. insert_resource() and insert_resource_conflict() |
|
* insert a new resource, and move any conflicting resources down to the |
|
* children of the new resource. |
|
* |
|
* insert_resource(), insert_resource_conflict() and remove_resource() are |
|
* intended for producers of resources, such as FW modules and bus drivers. |
|
*/ |
|
int remove_resource(struct resource *old) |
|
{ |
|
int retval; |
|
|
|
write_lock(&resource_lock); |
|
retval = __release_resource(old, false); |
|
write_unlock(&resource_lock); |
|
return retval; |
|
} |
|
EXPORT_SYMBOL_GPL(remove_resource); |
|
|
|
static int __adjust_resource(struct resource *res, resource_size_t start, |
|
resource_size_t size) |
|
{ |
|
struct resource *tmp, *parent = res->parent; |
|
resource_size_t end = start + size - 1; |
|
int result = -EBUSY; |
|
|
|
if (!parent) |
|
goto skip; |
|
|
|
if ((start < parent->start) || (end > parent->end)) |
|
goto out; |
|
|
|
if (res->sibling && (res->sibling->start <= end)) |
|
goto out; |
|
|
|
tmp = parent->child; |
|
if (tmp != res) { |
|
while (tmp->sibling != res) |
|
tmp = tmp->sibling; |
|
if (start <= tmp->end) |
|
goto out; |
|
} |
|
|
|
skip: |
|
for (tmp = res->child; tmp; tmp = tmp->sibling) |
|
if ((tmp->start < start) || (tmp->end > end)) |
|
goto out; |
|
|
|
res->start = start; |
|
res->end = end; |
|
result = 0; |
|
|
|
out: |
|
return result; |
|
} |
|
|
|
/** |
|
* adjust_resource - modify a resource's start and size |
|
* @res: resource to modify |
|
* @start: new start value |
|
* @size: new size |
|
* |
|
* Given an existing resource, change its start and size to match the |
|
* arguments. Returns 0 on success, -EBUSY if it can't fit. |
|
* Existing children of the resource are assumed to be immutable. |
|
*/ |
|
int adjust_resource(struct resource *res, resource_size_t start, |
|
resource_size_t size) |
|
{ |
|
int result; |
|
|
|
write_lock(&resource_lock); |
|
result = __adjust_resource(res, start, size); |
|
write_unlock(&resource_lock); |
|
return result; |
|
} |
|
EXPORT_SYMBOL(adjust_resource); |
|
|
|
static void __init |
|
__reserve_region_with_split(struct resource *root, resource_size_t start, |
|
resource_size_t end, const char *name) |
|
{ |
|
struct resource *parent = root; |
|
struct resource *conflict; |
|
struct resource *res = alloc_resource(GFP_ATOMIC); |
|
struct resource *next_res = NULL; |
|
int type = resource_type(root); |
|
|
|
if (!res) |
|
return; |
|
|
|
res->name = name; |
|
res->start = start; |
|
res->end = end; |
|
res->flags = type | IORESOURCE_BUSY; |
|
res->desc = IORES_DESC_NONE; |
|
|
|
while (1) { |
|
|
|
conflict = __request_resource(parent, res); |
|
if (!conflict) { |
|
if (!next_res) |
|
break; |
|
res = next_res; |
|
next_res = NULL; |
|
continue; |
|
} |
|
|
|
/* conflict covered whole area */ |
|
if (conflict->start <= res->start && |
|
conflict->end >= res->end) { |
|
free_resource(res); |
|
WARN_ON(next_res); |
|
break; |
|
} |
|
|
|
/* failed, split and try again */ |
|
if (conflict->start > res->start) { |
|
end = res->end; |
|
res->end = conflict->start - 1; |
|
if (conflict->end < end) { |
|
next_res = alloc_resource(GFP_ATOMIC); |
|
if (!next_res) { |
|
free_resource(res); |
|
break; |
|
} |
|
next_res->name = name; |
|
next_res->start = conflict->end + 1; |
|
next_res->end = end; |
|
next_res->flags = type | IORESOURCE_BUSY; |
|
next_res->desc = IORES_DESC_NONE; |
|
} |
|
} else { |
|
res->start = conflict->end + 1; |
|
} |
|
} |
|
|
|
} |
|
|
|
void __init |
|
reserve_region_with_split(struct resource *root, resource_size_t start, |
|
resource_size_t end, const char *name) |
|
{ |
|
int abort = 0; |
|
|
|
write_lock(&resource_lock); |
|
if (root->start > start || root->end < end) { |
|
pr_err("requested range [0x%llx-0x%llx] not in root %pr\n", |
|
(unsigned long long)start, (unsigned long long)end, |
|
root); |
|
if (start > root->end || end < root->start) |
|
abort = 1; |
|
else { |
|
if (end > root->end) |
|
end = root->end; |
|
if (start < root->start) |
|
start = root->start; |
|
pr_err("fixing request to [0x%llx-0x%llx]\n", |
|
(unsigned long long)start, |
|
(unsigned long long)end); |
|
} |
|
dump_stack(); |
|
} |
|
if (!abort) |
|
__reserve_region_with_split(root, start, end, name); |
|
write_unlock(&resource_lock); |
|
} |
|
|
|
/** |
|
* resource_alignment - calculate resource's alignment |
|
* @res: resource pointer |
|
* |
|
* Returns alignment on success, 0 (invalid alignment) on failure. |
|
*/ |
|
resource_size_t resource_alignment(struct resource *res) |
|
{ |
|
switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) { |
|
case IORESOURCE_SIZEALIGN: |
|
return resource_size(res); |
|
case IORESOURCE_STARTALIGN: |
|
return res->start; |
|
default: |
|
return 0; |
|
} |
|
} |
|
|
|
/* |
|
* This is compatibility stuff for IO resources. |
|
* |
|
* Note how this, unlike the above, knows about |
|
* the IO flag meanings (busy etc). |
|
* |
|
* request_region creates a new busy region. |
|
* |
|
* release_region releases a matching busy region. |
|
*/ |
|
|
|
static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait); |
|
|
|
static struct inode *iomem_inode; |
|
|
|
#ifdef CONFIG_IO_STRICT_DEVMEM |
|
static void revoke_iomem(struct resource *res) |
|
{ |
|
/* pairs with smp_store_release() in iomem_init_inode() */ |
|
struct inode *inode = smp_load_acquire(&iomem_inode); |
|
|
|
/* |
|
* Check that the initialization has completed. Losing the race |
|
* is ok because it means drivers are claiming resources before |
|
* the fs_initcall level of init and prevent iomem_get_mapping users |
|
* from establishing mappings. |
|
*/ |
|
if (!inode) |
|
return; |
|
|
|
/* |
|
* The expectation is that the driver has successfully marked |
|
* the resource busy by this point, so devmem_is_allowed() |
|
* should start returning false, however for performance this |
|
* does not iterate the entire resource range. |
|
*/ |
|
if (devmem_is_allowed(PHYS_PFN(res->start)) && |
|
devmem_is_allowed(PHYS_PFN(res->end))) { |
|
/* |
|
* *cringe* iomem=relaxed says "go ahead, what's the |
|
* worst that can happen?" |
|
*/ |
|
return; |
|
} |
|
|
|
unmap_mapping_range(inode->i_mapping, res->start, resource_size(res), 1); |
|
} |
|
#else |
|
static void revoke_iomem(struct resource *res) {} |
|
#endif |
|
|
|
struct address_space *iomem_get_mapping(void) |
|
{ |
|
/* |
|
* This function is only called from file open paths, hence guaranteed |
|
* that fs_initcalls have completed and no need to check for NULL. But |
|
* since revoke_iomem can be called before the initcall we still need |
|
* the barrier to appease checkers. |
|
*/ |
|
return smp_load_acquire(&iomem_inode)->i_mapping; |
|
} |
|
|
|
static int __request_region_locked(struct resource *res, struct resource *parent, |
|
resource_size_t start, resource_size_t n, |
|
const char *name, int flags) |
|
{ |
|
DECLARE_WAITQUEUE(wait, current); |
|
|
|
res->name = name; |
|
res->start = start; |
|
res->end = start + n - 1; |
|
|
|
for (;;) { |
|
struct resource *conflict; |
|
|
|
res->flags = resource_type(parent) | resource_ext_type(parent); |
|
res->flags |= IORESOURCE_BUSY | flags; |
|
res->desc = parent->desc; |
|
|
|
conflict = __request_resource(parent, res); |
|
if (!conflict) |
|
break; |
|
/* |
|
* mm/hmm.c reserves physical addresses which then |
|
* become unavailable to other users. Conflicts are |
|
* not expected. Warn to aid debugging if encountered. |
|
*/ |
|
if (conflict->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) { |
|
pr_warn("Unaddressable device %s %pR conflicts with %pR", |
|
conflict->name, conflict, res); |
|
} |
|
if (conflict != parent) { |
|
if (!(conflict->flags & IORESOURCE_BUSY)) { |
|
parent = conflict; |
|
continue; |
|
} |
|
} |
|
if (conflict->flags & flags & IORESOURCE_MUXED) { |
|
add_wait_queue(&muxed_resource_wait, &wait); |
|
write_unlock(&resource_lock); |
|
set_current_state(TASK_UNINTERRUPTIBLE); |
|
schedule(); |
|
remove_wait_queue(&muxed_resource_wait, &wait); |
|
write_lock(&resource_lock); |
|
continue; |
|
} |
|
/* Uhhuh, that didn't work out.. */ |
|
return -EBUSY; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
/** |
|
* __request_region - create a new busy resource region |
|
* @parent: parent resource descriptor |
|
* @start: resource start address |
|
* @n: resource region size |
|
* @name: reserving caller's ID string |
|
* @flags: IO resource flags |
|
*/ |
|
struct resource *__request_region(struct resource *parent, |
|
resource_size_t start, resource_size_t n, |
|
const char *name, int flags) |
|
{ |
|
struct resource *res = alloc_resource(GFP_KERNEL); |
|
int ret; |
|
|
|
if (!res) |
|
return NULL; |
|
|
|
write_lock(&resource_lock); |
|
ret = __request_region_locked(res, parent, start, n, name, flags); |
|
write_unlock(&resource_lock); |
|
|
|
if (ret) { |
|
free_resource(res); |
|
return NULL; |
|
} |
|
|
|
if (parent == &iomem_resource) |
|
revoke_iomem(res); |
|
|
|
return res; |
|
} |
|
EXPORT_SYMBOL(__request_region); |
|
|
|
/** |
|
* __release_region - release a previously reserved resource region |
|
* @parent: parent resource descriptor |
|
* @start: resource start address |
|
* @n: resource region size |
|
* |
|
* The described resource region must match a currently busy region. |
|
*/ |
|
void __release_region(struct resource *parent, resource_size_t start, |
|
resource_size_t n) |
|
{ |
|
struct resource **p; |
|
resource_size_t end; |
|
|
|
p = &parent->child; |
|
end = start + n - 1; |
|
|
|
write_lock(&resource_lock); |
|
|
|
for (;;) { |
|
struct resource *res = *p; |
|
|
|
if (!res) |
|
break; |
|
if (res->start <= start && res->end >= end) { |
|
if (!(res->flags & IORESOURCE_BUSY)) { |
|
p = &res->child; |
|
continue; |
|
} |
|
if (res->start != start || res->end != end) |
|
break; |
|
*p = res->sibling; |
|
write_unlock(&resource_lock); |
|
if (res->flags & IORESOURCE_MUXED) |
|
wake_up(&muxed_resource_wait); |
|
free_resource(res); |
|
return; |
|
} |
|
p = &res->sibling; |
|
} |
|
|
|
write_unlock(&resource_lock); |
|
|
|
printk(KERN_WARNING "Trying to free nonexistent resource " |
|
"<%016llx-%016llx>\n", (unsigned long long)start, |
|
(unsigned long long)end); |
|
} |
|
EXPORT_SYMBOL(__release_region); |
|
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE |
|
/** |
|
* release_mem_region_adjustable - release a previously reserved memory region |
|
* @start: resource start address |
|
* @size: resource region size |
|
* |
|
* This interface is intended for memory hot-delete. The requested region |
|
* is released from a currently busy memory resource. The requested region |
|
* must either match exactly or fit into a single busy resource entry. In |
|
* the latter case, the remaining resource is adjusted accordingly. |
|
* Existing children of the busy memory resource must be immutable in the |
|
* request. |
|
* |
|
* Note: |
|
* - Additional release conditions, such as overlapping region, can be |
|
* supported after they are confirmed as valid cases. |
|
* - When a busy memory resource gets split into two entries, the code |
|
* assumes that all children remain in the lower address entry for |
|
* simplicity. Enhance this logic when necessary. |
|
*/ |
|
void release_mem_region_adjustable(resource_size_t start, resource_size_t size) |
|
{ |
|
struct resource *parent = &iomem_resource; |
|
struct resource *new_res = NULL; |
|
bool alloc_nofail = false; |
|
struct resource **p; |
|
struct resource *res; |
|
resource_size_t end; |
|
|
|
end = start + size - 1; |
|
if (WARN_ON_ONCE((start < parent->start) || (end > parent->end))) |
|
return; |
|
|
|
/* |
|
* We free up quite a lot of memory on memory hotunplug (esp., memap), |
|
* just before releasing the region. This is highly unlikely to |
|
* fail - let's play save and make it never fail as the caller cannot |
|
* perform any error handling (e.g., trying to re-add memory will fail |
|
* similarly). |
|
*/ |
|
retry: |
|
new_res = alloc_resource(GFP_KERNEL | (alloc_nofail ? __GFP_NOFAIL : 0)); |
|
|
|
p = &parent->child; |
|
write_lock(&resource_lock); |
|
|
|
while ((res = *p)) { |
|
if (res->start >= end) |
|
break; |
|
|
|
/* look for the next resource if it does not fit into */ |
|
if (res->start > start || res->end < end) { |
|
p = &res->sibling; |
|
continue; |
|
} |
|
|
|
/* |
|
* All memory regions added from memory-hotplug path have the |
|
* flag IORESOURCE_SYSTEM_RAM. If the resource does not have |
|
* this flag, we know that we are dealing with a resource coming |
|
* from HMM/devm. HMM/devm use another mechanism to add/release |
|
* a resource. This goes via devm_request_mem_region and |
|
* devm_release_mem_region. |
|
* HMM/devm take care to release their resources when they want, |
|
* so if we are dealing with them, let us just back off here. |
|
*/ |
|
if (!(res->flags & IORESOURCE_SYSRAM)) { |
|
break; |
|
} |
|
|
|
if (!(res->flags & IORESOURCE_MEM)) |
|
break; |
|
|
|
if (!(res->flags & IORESOURCE_BUSY)) { |
|
p = &res->child; |
|
continue; |
|
} |
|
|
|
/* found the target resource; let's adjust accordingly */ |
|
if (res->start == start && res->end == end) { |
|
/* free the whole entry */ |
|
*p = res->sibling; |
|
free_resource(res); |
|
} else if (res->start == start && res->end != end) { |
|
/* adjust the start */ |
|
WARN_ON_ONCE(__adjust_resource(res, end + 1, |
|
res->end - end)); |
|
} else if (res->start != start && res->end == end) { |
|
/* adjust the end */ |
|
WARN_ON_ONCE(__adjust_resource(res, res->start, |
|
start - res->start)); |
|
} else { |
|
/* split into two entries - we need a new resource */ |
|
if (!new_res) { |
|
new_res = alloc_resource(GFP_ATOMIC); |
|
if (!new_res) { |
|
alloc_nofail = true; |
|
write_unlock(&resource_lock); |
|
goto retry; |
|
} |
|
} |
|
new_res->name = res->name; |
|
new_res->start = end + 1; |
|
new_res->end = res->end; |
|
new_res->flags = res->flags; |
|
new_res->desc = res->desc; |
|
new_res->parent = res->parent; |
|
new_res->sibling = res->sibling; |
|
new_res->child = NULL; |
|
|
|
if (WARN_ON_ONCE(__adjust_resource(res, res->start, |
|
start - res->start))) |
|
break; |
|
res->sibling = new_res; |
|
new_res = NULL; |
|
} |
|
|
|
break; |
|
} |
|
|
|
write_unlock(&resource_lock); |
|
free_resource(new_res); |
|
} |
|
#endif /* CONFIG_MEMORY_HOTREMOVE */ |
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG |
|
static bool system_ram_resources_mergeable(struct resource *r1, |
|
struct resource *r2) |
|
{ |
|
/* We assume either r1 or r2 is IORESOURCE_SYSRAM_MERGEABLE. */ |
|
return r1->flags == r2->flags && r1->end + 1 == r2->start && |
|
r1->name == r2->name && r1->desc == r2->desc && |
|
!r1->child && !r2->child; |
|
} |
|
|
|
/** |
|
* merge_system_ram_resource - mark the System RAM resource mergeable and try to |
|
* merge it with adjacent, mergeable resources |
|
* @res: resource descriptor |
|
* |
|
* This interface is intended for memory hotplug, whereby lots of contiguous |
|
* system ram resources are added (e.g., via add_memory*()) by a driver, and |
|
* the actual resource boundaries are not of interest (e.g., it might be |
|
* relevant for DIMMs). Only resources that are marked mergeable, that have the |
|
* same parent, and that don't have any children are considered. All mergeable |
|
* resources must be immutable during the request. |
|
* |
|
* Note: |
|
* - The caller has to make sure that no pointers to resources that are |
|
* marked mergeable are used anymore after this call - the resource might |
|
* be freed and the pointer might be stale! |
|
* - release_mem_region_adjustable() will split on demand on memory hotunplug |
|
*/ |
|
void merge_system_ram_resource(struct resource *res) |
|
{ |
|
const unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; |
|
struct resource *cur; |
|
|
|
if (WARN_ON_ONCE((res->flags & flags) != flags)) |
|
return; |
|
|
|
write_lock(&resource_lock); |
|
res->flags |= IORESOURCE_SYSRAM_MERGEABLE; |
|
|
|
/* Try to merge with next item in the list. */ |
|
cur = res->sibling; |
|
if (cur && system_ram_resources_mergeable(res, cur)) { |
|
res->end = cur->end; |
|
res->sibling = cur->sibling; |
|
free_resource(cur); |
|
} |
|
|
|
/* Try to merge with previous item in the list. */ |
|
cur = res->parent->child; |
|
while (cur && cur->sibling != res) |
|
cur = cur->sibling; |
|
if (cur && system_ram_resources_mergeable(cur, res)) { |
|
cur->end = res->end; |
|
cur->sibling = res->sibling; |
|
free_resource(res); |
|
} |
|
write_unlock(&resource_lock); |
|
} |
|
#endif /* CONFIG_MEMORY_HOTPLUG */ |
|
|
|
/* |
|
* Managed region resource |
|
*/ |
|
static void devm_resource_release(struct device *dev, void *ptr) |
|
{ |
|
struct resource **r = ptr; |
|
|
|
release_resource(*r); |
|
} |
|
|
|
/** |
|
* devm_request_resource() - request and reserve an I/O or memory resource |
|
* @dev: device for which to request the resource |
|
* @root: root of the resource tree from which to request the resource |
|
* @new: descriptor of the resource to request |
|
* |
|
* This is a device-managed version of request_resource(). There is usually |
|
* no need to release resources requested by this function explicitly since |
|
* that will be taken care of when the device is unbound from its driver. |
|
* If for some reason the resource needs to be released explicitly, because |
|
* of ordering issues for example, drivers must call devm_release_resource() |
|
* rather than the regular release_resource(). |
|
* |
|
* When a conflict is detected between any existing resources and the newly |
|
* requested resource, an error message will be printed. |
|
* |
|
* Returns 0 on success or a negative error code on failure. |
|
*/ |
|
int devm_request_resource(struct device *dev, struct resource *root, |
|
struct resource *new) |
|
{ |
|
struct resource *conflict, **ptr; |
|
|
|
ptr = devres_alloc(devm_resource_release, sizeof(*ptr), GFP_KERNEL); |
|
if (!ptr) |
|
return -ENOMEM; |
|
|
|
*ptr = new; |
|
|
|
conflict = request_resource_conflict(root, new); |
|
if (conflict) { |
|
dev_err(dev, "resource collision: %pR conflicts with %s %pR\n", |
|
new, conflict->name, conflict); |
|
devres_free(ptr); |
|
return -EBUSY; |
|
} |
|
|
|
devres_add(dev, ptr); |
|
return 0; |
|
} |
|
EXPORT_SYMBOL(devm_request_resource); |
|
|
|
static int devm_resource_match(struct device *dev, void *res, void *data) |
|
{ |
|
struct resource **ptr = res; |
|
|
|
return *ptr == data; |
|
} |
|
|
|
/** |
|
* devm_release_resource() - release a previously requested resource |
|
* @dev: device for which to release the resource |
|
* @new: descriptor of the resource to release |
|
* |
|
* Releases a resource previously requested using devm_request_resource(). |
|
*/ |
|
void devm_release_resource(struct device *dev, struct resource *new) |
|
{ |
|
WARN_ON(devres_release(dev, devm_resource_release, devm_resource_match, |
|
new)); |
|
} |
|
EXPORT_SYMBOL(devm_release_resource); |
|
|
|
struct region_devres { |
|
struct resource *parent; |
|
resource_size_t start; |
|
resource_size_t n; |
|
}; |
|
|
|
static void devm_region_release(struct device *dev, void *res) |
|
{ |
|
struct region_devres *this = res; |
|
|
|
__release_region(this->parent, this->start, this->n); |
|
} |
|
|
|
static int devm_region_match(struct device *dev, void *res, void *match_data) |
|
{ |
|
struct region_devres *this = res, *match = match_data; |
|
|
|
return this->parent == match->parent && |
|
this->start == match->start && this->n == match->n; |
|
} |
|
|
|
struct resource * |
|
__devm_request_region(struct device *dev, struct resource *parent, |
|
resource_size_t start, resource_size_t n, const char *name) |
|
{ |
|
struct region_devres *dr = NULL; |
|
struct resource *res; |
|
|
|
dr = devres_alloc(devm_region_release, sizeof(struct region_devres), |
|
GFP_KERNEL); |
|
if (!dr) |
|
return NULL; |
|
|
|
dr->parent = parent; |
|
dr->start = start; |
|
dr->n = n; |
|
|
|
res = __request_region(parent, start, n, name, 0); |
|
if (res) |
|
devres_add(dev, dr); |
|
else |
|
devres_free(dr); |
|
|
|
return res; |
|
} |
|
EXPORT_SYMBOL(__devm_request_region); |
|
|
|
void __devm_release_region(struct device *dev, struct resource *parent, |
|
resource_size_t start, resource_size_t n) |
|
{ |
|
struct region_devres match_data = { parent, start, n }; |
|
|
|
__release_region(parent, start, n); |
|
WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match, |
|
&match_data)); |
|
} |
|
EXPORT_SYMBOL(__devm_release_region); |
|
|
|
/* |
|
* Reserve I/O ports or memory based on "reserve=" kernel parameter. |
|
*/ |
|
#define MAXRESERVE 4 |
|
static int __init reserve_setup(char *str) |
|
{ |
|
static int reserved; |
|
static struct resource reserve[MAXRESERVE]; |
|
|
|
for (;;) { |
|
unsigned int io_start, io_num; |
|
int x = reserved; |
|
struct resource *parent; |
|
|
|
if (get_option(&str, &io_start) != 2) |
|
break; |
|
if (get_option(&str, &io_num) == 0) |
|
break; |
|
if (x < MAXRESERVE) { |
|
struct resource *res = reserve + x; |
|
|
|
/* |
|
* If the region starts below 0x10000, we assume it's |
|
* I/O port space; otherwise assume it's memory. |
|
*/ |
|
if (io_start < 0x10000) { |
|
res->flags = IORESOURCE_IO; |
|
parent = &ioport_resource; |
|
} else { |
|
res->flags = IORESOURCE_MEM; |
|
parent = &iomem_resource; |
|
} |
|
res->name = "reserved"; |
|
res->start = io_start; |
|
res->end = io_start + io_num - 1; |
|
res->flags |= IORESOURCE_BUSY; |
|
res->desc = IORES_DESC_NONE; |
|
res->child = NULL; |
|
if (request_resource(parent, res) == 0) |
|
reserved = x+1; |
|
} |
|
} |
|
return 1; |
|
} |
|
__setup("reserve=", reserve_setup); |
|
|
|
/* |
|
* Check if the requested addr and size spans more than any slot in the |
|
* iomem resource tree. |
|
*/ |
|
int iomem_map_sanity_check(resource_size_t addr, unsigned long size) |
|
{ |
|
struct resource *p = &iomem_resource; |
|
int err = 0; |
|
loff_t l; |
|
|
|
read_lock(&resource_lock); |
|
for (p = p->child; p ; p = r_next(NULL, p, &l)) { |
|
/* |
|
* We can probably skip the resources without |
|
* IORESOURCE_IO attribute? |
|
*/ |
|
if (p->start >= addr + size) |
|
continue; |
|
if (p->end < addr) |
|
continue; |
|
if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && |
|
PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1)) |
|
continue; |
|
/* |
|
* if a resource is "BUSY", it's not a hardware resource |
|
* but a driver mapping of such a resource; we don't want |
|
* to warn for those; some drivers legitimately map only |
|
* partial hardware resources. (example: vesafb) |
|
*/ |
|
if (p->flags & IORESOURCE_BUSY) |
|
continue; |
|
|
|
printk(KERN_WARNING "resource sanity check: requesting [mem %#010llx-%#010llx], which spans more than %s %pR\n", |
|
(unsigned long long)addr, |
|
(unsigned long long)(addr + size - 1), |
|
p->name, p); |
|
err = -1; |
|
break; |
|
} |
|
read_unlock(&resource_lock); |
|
|
|
return err; |
|
} |
|
|
|
#ifdef CONFIG_STRICT_DEVMEM |
|
static int strict_iomem_checks = 1; |
|
#else |
|
static int strict_iomem_checks; |
|
#endif |
|
|
|
/* |
|
* check if an address is reserved in the iomem resource tree |
|
* returns true if reserved, false if not reserved. |
|
*/ |
|
bool iomem_is_exclusive(u64 addr) |
|
{ |
|
struct resource *p = &iomem_resource; |
|
bool err = false; |
|
loff_t l; |
|
int size = PAGE_SIZE; |
|
|
|
if (!strict_iomem_checks) |
|
return false; |
|
|
|
addr = addr & PAGE_MASK; |
|
|
|
read_lock(&resource_lock); |
|
for (p = p->child; p ; p = r_next(NULL, p, &l)) { |
|
/* |
|
* We can probably skip the resources without |
|
* IORESOURCE_IO attribute? |
|
*/ |
|
if (p->start >= addr + size) |
|
break; |
|
if (p->end < addr) |
|
continue; |
|
/* |
|
* A resource is exclusive if IORESOURCE_EXCLUSIVE is set |
|
* or CONFIG_IO_STRICT_DEVMEM is enabled and the |
|
* resource is busy. |
|
*/ |
|
if ((p->flags & IORESOURCE_BUSY) == 0) |
|
continue; |
|
if (IS_ENABLED(CONFIG_IO_STRICT_DEVMEM) |
|
|| p->flags & IORESOURCE_EXCLUSIVE) { |
|
err = true; |
|
break; |
|
} |
|
} |
|
read_unlock(&resource_lock); |
|
|
|
return err; |
|
} |
|
|
|
struct resource_entry *resource_list_create_entry(struct resource *res, |
|
size_t extra_size) |
|
{ |
|
struct resource_entry *entry; |
|
|
|
entry = kzalloc(sizeof(*entry) + extra_size, GFP_KERNEL); |
|
if (entry) { |
|
INIT_LIST_HEAD(&entry->node); |
|
entry->res = res ? res : &entry->__res; |
|
} |
|
|
|
return entry; |
|
} |
|
EXPORT_SYMBOL(resource_list_create_entry); |
|
|
|
void resource_list_free(struct list_head *head) |
|
{ |
|
struct resource_entry *entry, *tmp; |
|
|
|
list_for_each_entry_safe(entry, tmp, head, node) |
|
resource_list_destroy_entry(entry); |
|
} |
|
EXPORT_SYMBOL(resource_list_free); |
|
|
|
#ifdef CONFIG_DEVICE_PRIVATE |
|
static struct resource *__request_free_mem_region(struct device *dev, |
|
struct resource *base, unsigned long size, const char *name) |
|
{ |
|
resource_size_t end, addr; |
|
struct resource *res; |
|
struct region_devres *dr = NULL; |
|
|
|
size = ALIGN(size, 1UL << PA_SECTION_SHIFT); |
|
end = min_t(unsigned long, base->end, (1UL << MAX_PHYSMEM_BITS) - 1); |
|
addr = end - size + 1UL; |
|
|
|
res = alloc_resource(GFP_KERNEL); |
|
if (!res) |
|
return ERR_PTR(-ENOMEM); |
|
|
|
if (dev) { |
|
dr = devres_alloc(devm_region_release, |
|
sizeof(struct region_devres), GFP_KERNEL); |
|
if (!dr) { |
|
free_resource(res); |
|
return ERR_PTR(-ENOMEM); |
|
} |
|
} |
|
|
|
write_lock(&resource_lock); |
|
for (; addr > size && addr >= base->start; addr -= size) { |
|
if (__region_intersects(addr, size, 0, IORES_DESC_NONE) != |
|
REGION_DISJOINT) |
|
continue; |
|
|
|
if (__request_region_locked(res, &iomem_resource, addr, size, |
|
name, 0)) |
|
break; |
|
|
|
if (dev) { |
|
dr->parent = &iomem_resource; |
|
dr->start = addr; |
|
dr->n = size; |
|
devres_add(dev, dr); |
|
} |
|
|
|
res->desc = IORES_DESC_DEVICE_PRIVATE_MEMORY; |
|
write_unlock(&resource_lock); |
|
|
|
/* |
|
* A driver is claiming this region so revoke any mappings. |
|
*/ |
|
revoke_iomem(res); |
|
return res; |
|
} |
|
write_unlock(&resource_lock); |
|
|
|
free_resource(res); |
|
if (dr) |
|
devres_free(dr); |
|
|
|
return ERR_PTR(-ERANGE); |
|
} |
|
|
|
/** |
|
* devm_request_free_mem_region - find free region for device private memory |
|
* |
|
* @dev: device struct to bind the resource to |
|
* @size: size in bytes of the device memory to add |
|
* @base: resource tree to look in |
|
* |
|
* This function tries to find an empty range of physical address big enough to |
|
* contain the new resource, so that it can later be hotplugged as ZONE_DEVICE |
|
* memory, which in turn allocates struct pages. |
|
*/ |
|
struct resource *devm_request_free_mem_region(struct device *dev, |
|
struct resource *base, unsigned long size) |
|
{ |
|
return __request_free_mem_region(dev, base, size, dev_name(dev)); |
|
} |
|
EXPORT_SYMBOL_GPL(devm_request_free_mem_region); |
|
|
|
struct resource *request_free_mem_region(struct resource *base, |
|
unsigned long size, const char *name) |
|
{ |
|
return __request_free_mem_region(NULL, base, size, name); |
|
} |
|
EXPORT_SYMBOL_GPL(request_free_mem_region); |
|
|
|
#endif /* CONFIG_DEVICE_PRIVATE */ |
|
|
|
static int __init strict_iomem(char *str) |
|
{ |
|
if (strstr(str, "relaxed")) |
|
strict_iomem_checks = 0; |
|
if (strstr(str, "strict")) |
|
strict_iomem_checks = 1; |
|
return 1; |
|
} |
|
|
|
static int iomem_fs_init_fs_context(struct fs_context *fc) |
|
{ |
|
return init_pseudo(fc, DEVMEM_MAGIC) ? 0 : -ENOMEM; |
|
} |
|
|
|
static struct file_system_type iomem_fs_type = { |
|
.name = "iomem", |
|
.owner = THIS_MODULE, |
|
.init_fs_context = iomem_fs_init_fs_context, |
|
.kill_sb = kill_anon_super, |
|
}; |
|
|
|
static int __init iomem_init_inode(void) |
|
{ |
|
static struct vfsmount *iomem_vfs_mount; |
|
static int iomem_fs_cnt; |
|
struct inode *inode; |
|
int rc; |
|
|
|
rc = simple_pin_fs(&iomem_fs_type, &iomem_vfs_mount, &iomem_fs_cnt); |
|
if (rc < 0) { |
|
pr_err("Cannot mount iomem pseudo filesystem: %d\n", rc); |
|
return rc; |
|
} |
|
|
|
inode = alloc_anon_inode(iomem_vfs_mount->mnt_sb); |
|
if (IS_ERR(inode)) { |
|
rc = PTR_ERR(inode); |
|
pr_err("Cannot allocate inode for iomem: %d\n", rc); |
|
simple_release_fs(&iomem_vfs_mount, &iomem_fs_cnt); |
|
return rc; |
|
} |
|
|
|
/* |
|
* Publish iomem revocation inode initialized. |
|
* Pairs with smp_load_acquire() in revoke_iomem(). |
|
*/ |
|
smp_store_release(&iomem_inode, inode); |
|
|
|
return 0; |
|
} |
|
|
|
fs_initcall(iomem_init_inode); |
|
|
|
__setup("iomem=", strict_iomem);
|
|
|