/* * linux/kernel/resource.c * * Copyright (C) 1999 Linus Torvalds * Copyright (C) 1999 Martin Mares <mj@ucw.cz> * * Arbitrary resource management. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/export.h>#include <linux/errno.h>#include <linux/ioport.h>#include <linux/init.h>#include <linux/slab.h>#include <linux/spinlock.h>#include <linux/fs.h>#include <linux/proc_fs.h>#include <linux/sched.h>#include <linux/seq_file.h>#include <linux/device.h>#include <linux/pfn.h>#include <asm/io.h> struct resource ioport_resource = { .name = "PCI IO", .start = 0, .end = IO_SPACE_LIMIT, .flags = IORESOURCE_IO,};EXPORT_SYMBOL(ioport_resource); struct resource iomem_resource = { .name = "PCI mem", .start = 0, .end = -1, .flags = IORESOURCE_MEM,};EXPORT_SYMBOL(iomem_resource); /* constraints to be met while allocating resources */struct resource_constraint { resource_size_t min, max, align; resource_size_t (*alignf)(void *, const struct resource *, resource_size_t, resource_size_t); void *alignf_data;}; static DEFINE_RWLOCK(resource_lock); static void *r_next(struct seq_file *m, void *v, loff_t *pos){ struct resource *p = v; (*pos)++; if (p->child) return p->child; while (!p->sibling && p->parent) p = p->parent; return p->sibling;} #ifdef CONFIG_PROC_FS enum { MAX_IORES_LEVEL = 5 }; static void *r_start(struct seq_file *m, loff_t *pos) __acquires(resource_lock){ struct resource *p = m->private; loff_t l = 0; read_lock(&resource_lock); for (p = p->child; p && l < *pos; p = r_next(m, p, &l)) ; return p;} static void r_stop(struct seq_file *m, void *v) __releases(resource_lock){ read_unlock(&resource_lock);} static int r_show(struct seq_file *m, void *v){ struct resource *root = m->private; struct resource *r = v, *p; int width = root->end < 0x10000 ? 4 : 8; int depth; for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent) if (p->parent == root) break; seq_printf(m, "%*s%0*llx-%0*llx : %s\n", depth * 2, "", width, (unsigned long long) r->start, width, (unsigned long long) r->end, r->name ? r->name : "<BAD>"); return 0;} static const struct seq_operations resource_op = { .start = r_start, .next = r_next, .stop = r_stop, .show = r_show,}; static int ioports_open(struct inode *inode, struct file *file){ int res = seq_open(file, &resource_op); if (!res) { struct seq_file *m = file->private_data; m->private = &ioport_resource; } return res;} static int iomem_open(struct inode *inode, struct file *file){ int res = seq_open(file, &resource_op); if (!res) { struct seq_file *m = file->private_data; m->private = &iomem_resource; } return res;} static const struct file_operations proc_ioports_operations = { .open = ioports_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release,}; static const struct file_operations proc_iomem_operations = { .open = iomem_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release,}; static int __init ioresources_init(void){ proc_create("ioports", 0, NULL, &proc_ioports_operations); proc_create("iomem", 0, NULL, &proc_iomem_operations); return 0;}__initcall(ioresources_init); #endif /* CONFIG_PROC_FS */ /* Return the conflict entry if you can't request it */static struct resource * __request_resource(struct resource *root, struct resource *new){ resource_size_t start = new->start; resource_size_t end = new->end; struct resource *tmp, **p; if (end < start) return root; if (start < root->start) return root; if (end > root->end) return root; p = &root->child; for (;;) { tmp = *p; if (!tmp || tmp->start > end) { new->sibling = tmp; *p = new; new->parent = root; return NULL; } p = &tmp->sibling; if (tmp->end < start) continue; return tmp; }} static int __release_resource(struct resource *old){ struct resource *tmp, **p; p = &old->parent->child; for (;;) { tmp = *p; if (!tmp) break; if (tmp == old) { *p = tmp->sibling; old->parent = NULL; return 0; } p = &tmp->sibling; } return -EINVAL;} static void __release_child_resources(struct resource *r){ struct resource *tmp, *p; resource_size_t size; p = r->child; r->child = NULL; while (p) { tmp = p; p = p->sibling; tmp->parent = NULL; tmp->sibling = NULL; __release_child_resources(tmp); printk(KERN_DEBUG "release child resource %pR\n", tmp); /* need to restore size, and keep flags */ size = resource_size(tmp); tmp->start = 0; tmp->end = size - 1; }} void release_child_resources(struct resource *r){ write_lock(&resource_lock); __release_child_resources(r); write_unlock(&resource_lock);} /** * request_resource_conflict - request and reserve an I/O or memory resource * @root: root resource descriptor * @new: resource descriptor desired by caller * * Returns 0 for success, conflict resource on error. */struct resource *request_resource_conflict(struct resource *root, struct resource *new){ struct resource *conflict; write_lock(&resource_lock); conflict = __request_resource(root, new); write_unlock(&resource_lock); return conflict;} /** * request_resource - request and reserve an I/O or memory resource * @root: root resource descriptor * @new: resource descriptor desired by caller * * Returns 0 for success, negative error code on error. */int request_resource(struct resource *root, struct resource *new){ struct resource *conflict; conflict = request_resource_conflict(root, new); return conflict ? -EBUSY : 0;} EXPORT_SYMBOL(request_resource); /** * release_resource - release a previously reserved resource * @old: resource pointer */int release_resource(struct resource *old){ int retval; write_lock(&resource_lock); retval = __release_resource(old); write_unlock(&resource_lock); return retval;} EXPORT_SYMBOL(release_resource); #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)/* * Finds the lowest memory reosurce exists within [res->start.res->end) * the caller must specify res->start, res->end, res->flags and "name". * If found, returns 0, res is overwritten, if not found, returns -1. */static int find_next_system_ram(struct resource *res, char *name){ resource_size_t start, end; struct resource *p; BUG_ON(!res); start = res->start; end = res->end; BUG_ON(start >= end); read_lock(&resource_lock); for (p = iomem_resource.child; p ; p = p->sibling) { /* system ram is just marked as IORESOURCE_MEM */ if (p->flags != res->flags) continue; if (name && strcmp(p->name, name)) continue; if (p->start > end) { p = NULL; break; } if ((p->end >= start) && (p->start < end)) break; } read_unlock(&resource_lock); if (!p) return -1; /* copy data */ if (res->start < p->start) res->start = p->start; if (res->end > p->end) res->end = p->end; return 0;} /* * This function calls callback against all memory range of "System RAM" * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY. * Now, this function is only for "System RAM". */int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, void *arg, int (*func)(unsigned long, unsigned long, void *)){ struct resource res; unsigned long pfn, end_pfn; u64 orig_end; int ret = -1; res.start = (u64) start_pfn << PAGE_SHIFT; res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; orig_end = res.end; while ((res.start < res.end) && (find_next_system_ram(&res, "System RAM") >= 0)) { pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT; end_pfn = (res.end + 1) >> PAGE_SHIFT; if (end_pfn > pfn) ret = (*func)(pfn, end_pfn - pfn, arg); if (ret) break; res.start = res.end + 1; res.end = orig_end; } return ret;} #endif static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg){ return 1;}/* * This generic page_is_ram() returns true if specified address is * registered as "System RAM" in iomem_resource list. */int __weak page_is_ram(unsigned long pfn){ return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;} void __weak arch_remove_reservations(struct resource *avail){} static resource_size_t simple_align_resource(void *data, const struct resource *avail, resource_size_t size, resource_size_t align){ return avail->start;} static void resource_clip(struct resource *res, resource_size_t min, resource_size_t max){ if (res->start < min) res->start = min; if (res->end > max) res->end = max;} static bool resource_contains(struct resource *res1, struct resource *res2){ return res1->start <= res2->start && res1->end >= res2->end;} /* * Find empty slot in the resource tree with the given range and * alignment constraints */static int __find_resource(struct resource *root, struct resource *old, struct resource *new, resource_size_t size, struct resource_constraint *constraint){ struct resource *this = root->child; struct resource tmp = *new, avail, alloc; tmp.flags = new->flags; tmp.start = root->start; /* * Skip past an allocated resource that starts at 0, since the assignment * 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) tmp.end = (this == old) ? this->end : this->start - 1; else 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 = *new; avail.start = ALIGN(tmp.start, constraint->align); avail.end = tmp.end; if (avail.start >= tmp.start) { alloc.start = constraint->alignf(constraint->alignf_data, &avail, size, constraint->align); alloc.end = alloc.start + size - 1; if (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. */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;Lines 1–500 of 1208. Load more
/* * linux/kernel/resource.c * * Copyright (C) 1999 Linus Torvalds * Copyright (C) 1999 Martin Mares <mj@ucw.cz> * * Arbitrary resource management. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/export.h> #include <linux/errno.h> #include <linux/ioport.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/fs.h> #include <linux/proc_fs.h> #include <linux/sched.h> #include <linux/seq_file.h> #include <linux/device.h> #include <linux/pfn.h> #include <asm/io.h> struct resource ioport_resource = { .name = "PCI IO", .start = 0, .end = IO_SPACE_LIMIT, .flags = IORESOURCE_IO, }; EXPORT_SYMBOL(ioport_resource); struct resource iomem_resource = { .name = "PCI mem", .start = 0, .end = -1, .flags = IORESOURCE_MEM, }; EXPORT_SYMBOL(iomem_resource); /* constraints to be met while allocating resources */ struct resource_constraint { resource_size_t min, max, align; resource_size_t (*alignf)(void *, const struct resource *, resource_size_t, resource_size_t); void *alignf_data; }; static DEFINE_RWLOCK(resource_lock); static void *r_next(struct seq_file *m, void *v, loff_t *pos) { struct resource *p = v; (*pos)++; if (p->child) return p->child; while (!p->sibling && p->parent) p = p->parent; return p->sibling; } #ifdef CONFIG_PROC_FS enum { MAX_IORES_LEVEL = 5 }; static void *r_start(struct seq_file *m, loff_t *pos) __acquires(resource_lock) { struct resource *p = m->private; loff_t l = 0; read_lock(&resource_lock); for (p = p->child; p && l < *pos; p = r_next(m, p, &l)) ; return p; } static void r_stop(struct seq_file *m, void *v) __releases(resource_lock) { read_unlock(&resource_lock); } static int r_show(struct seq_file *m, void *v) { struct resource *root = m->private; struct resource *r = v, *p; int width = root->end < 0x10000 ? 4 : 8; int depth; for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent) if (p->parent == root) break; seq_printf(m, "%*s%0*llx-%0*llx : %s\n", depth * 2, "", width, (unsigned long long) r->start, width, (unsigned long long) r->end, r->name ? r->name : "<BAD>"); return 0; } static const struct seq_operations resource_op = { .start = r_start, .next = r_next, .stop = r_stop, .show = r_show, }; static int ioports_open(struct inode *inode, struct file *file) { int res = seq_open(file, &resource_op); if (!res) { struct seq_file *m = file->private_data; m->private = &ioport_resource; } return res; } static int iomem_open(struct inode *inode, struct file *file) { int res = seq_open(file, &resource_op); if (!res) { struct seq_file *m = file->private_data; m->private = &iomem_resource; } return res; } static const struct file_operations proc_ioports_operations = { .open = ioports_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; static const struct file_operations proc_iomem_operations = { .open = iomem_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; static int __init ioresources_init(void) { proc_create("ioports", 0, NULL, &proc_ioports_operations); proc_create("iomem", 0, NULL, &proc_iomem_operations); return 0; } __initcall(ioresources_init); #endif /* CONFIG_PROC_FS */ /* Return the conflict entry if you can't request it */ static struct resource * __request_resource(struct resource *root, struct resource *new) { resource_size_t start = new->start; resource_size_t end = new->end; struct resource *tmp, **p; if (end < start) return root; if (start < root->start) return root; if (end > root->end) return root; p = &root->child; for (;;) { tmp = *p; if (!tmp || tmp->start > end) { new->sibling = tmp; *p = new; new->parent = root; return NULL; } p = &tmp->sibling; if (tmp->end < start) continue; return tmp; } } static int __release_resource(struct resource *old) { struct resource *tmp, **p; p = &old->parent->child; for (;;) { tmp = *p; if (!tmp) break; if (tmp == old) { *p = tmp->sibling; old->parent = NULL; return 0; } p = &tmp->sibling; } return -EINVAL; } static void __release_child_resources(struct resource *r) { struct resource *tmp, *p; resource_size_t size; p = r->child; r->child = NULL; while (p) { tmp = p; p = p->sibling; tmp->parent = NULL; tmp->sibling = NULL; __release_child_resources(tmp); printk(KERN_DEBUG "release child resource %pR\n", tmp); /* need to restore size, and keep flags */ size = resource_size(tmp); tmp->start = 0; tmp->end = size - 1; } } void release_child_resources(struct resource *r) { write_lock(&resource_lock); __release_child_resources(r); write_unlock(&resource_lock); } /** * request_resource_conflict - request and reserve an I/O or memory resource * @root: root resource descriptor * @new: resource descriptor desired by caller * * Returns 0 for success, conflict resource on error. */ struct resource *request_resource_conflict(struct resource *root, struct resource *new) { struct resource *conflict; write_lock(&resource_lock); conflict = __request_resource(root, new); write_unlock(&resource_lock); return conflict; } /** * request_resource - request and reserve an I/O or memory resource * @root: root resource descriptor * @new: resource descriptor desired by caller * * Returns 0 for success, negative error code on error. */ int request_resource(struct resource *root, struct resource *new) { struct resource *conflict; conflict = request_resource_conflict(root, new); return conflict ? -EBUSY : 0; } EXPORT_SYMBOL(request_resource); /** * release_resource - release a previously reserved resource * @old: resource pointer */ int release_resource(struct resource *old) { int retval; write_lock(&resource_lock); retval = __release_resource(old); write_unlock(&resource_lock); return retval; } EXPORT_SYMBOL(release_resource); #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY) /* * Finds the lowest memory reosurce exists within [res->start.res->end) * the caller must specify res->start, res->end, res->flags and "name". * If found, returns 0, res is overwritten, if not found, returns -1. */ static int find_next_system_ram(struct resource *res, char *name) { resource_size_t start, end; struct resource *p; BUG_ON(!res); start = res->start; end = res->end; BUG_ON(start >= end); read_lock(&resource_lock); for (p = iomem_resource.child; p ; p = p->sibling) { /* system ram is just marked as IORESOURCE_MEM */ if (p->flags != res->flags) continue; if (name && strcmp(p->name, name)) continue; if (p->start > end) { p = NULL; break; } if ((p->end >= start) && (p->start < end)) break; } read_unlock(&resource_lock); if (!p) return -1; /* copy data */ if (res->start < p->start) res->start = p->start; if (res->end > p->end) res->end = p->end; return 0; } /* * This function calls callback against all memory range of "System RAM" * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY. * Now, this function is only for "System RAM". */ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, void *arg, int (*func)(unsigned long, unsigned long, void *)) { struct resource res; unsigned long pfn, end_pfn; u64 orig_end; int ret = -1; res.start = (u64) start_pfn << PAGE_SHIFT; res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; orig_end = res.end; while ((res.start < res.end) && (find_next_system_ram(&res, "System RAM") >= 0)) { pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT; end_pfn = (res.end + 1) >> PAGE_SHIFT; if (end_pfn > pfn) ret = (*func)(pfn, end_pfn - pfn, arg); if (ret) break; res.start = res.end + 1; res.end = orig_end; } return ret; } #endif static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg) { return 1; } /* * This generic page_is_ram() returns true if specified address is * registered as "System RAM" in iomem_resource list. */ int __weak page_is_ram(unsigned long pfn) { return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1; } void __weak arch_remove_reservations(struct resource *avail) { } static resource_size_t simple_align_resource(void *data, const struct resource *avail, resource_size_t size, resource_size_t align) { return avail->start; } static void resource_clip(struct resource *res, resource_size_t min, resource_size_t max) { if (res->start < min) res->start = min; if (res->end > max) res->end = max; } static bool resource_contains(struct resource *res1, struct resource *res2) { return res1->start <= res2->start && res1->end >= res2->end; } /* * Find empty slot in the resource tree with the given range and * alignment constraints */ static int __find_resource(struct resource *root, struct resource *old, struct resource *new, resource_size_t size, struct resource_constraint *constraint) { struct resource *this = root->child; struct resource tmp = *new, avail, alloc; tmp.flags = new->flags; tmp.start = root->start; /* * Skip past an allocated resource that starts at 0, since the assignment * 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) tmp.end = (this == old) ? this->end : this->start - 1; else 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 = *new; avail.start = ALIGN(tmp.start, constraint->align); avail.end = tmp.end; if (avail.start >= tmp.start) { alloc.start = constraint->alignf(constraint->alignf_data, &avail, size, constraint->align); alloc.end = alloc.start + size - 1; if (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. */ 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;