| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Linus Torvalds (pre-git) | 1364 | 17.27% | 28 | 15.14% |
| Dan J Williams | 669 | 8.47% | 8 | 4.32% |
| Toshi Kani | 605 | 7.66% | 11 | 5.95% |
| David Hildenbrand | 346 | 4.38% | 7 | 3.78% |
| Björn Helgaas | 319 | 4.04% | 13 | 7.03% |
| Ram Pai | 306 | 3.87% | 2 | 1.08% |
| Yinghai Lu | 287 | 3.63% | 3 | 1.62% |
| Tejun Heo | 269 | 3.41% | 1 | 0.54% |
| Linus Torvalds | 252 | 3.19% | 9 | 4.86% |
| Kamezawa Hiroyuki | 246 | 3.11% | 4 | 2.16% |
| Baoquan He | 232 | 2.94% | 1 | 0.54% |
| Alistair Popple | 224 | 2.84% | 3 | 1.62% |
| Al Viro | 200 | 2.53% | 1 | 0.54% |
| Matthew Wilcox | 195 | 2.47% | 2 | 1.08% |
| Thierry Reding | 180 | 2.28% | 1 | 0.54% |
| Benjamin Herrenschmidt | 175 | 2.22% | 1 | 0.54% |
| Christoph Hellwig | 167 | 2.11% | 3 | 1.62% |
| Daniel Vetter | 153 | 1.94% | 1 | 0.54% |
| Arjan van de Ven | 134 | 1.70% | 2 | 1.08% |
| Suresh B. Siddha | 124 | 1.57% | 2 | 1.08% |
| T Makphaibulchoke | 112 | 1.42% | 1 | 0.54% |
| Jiang Liu | 105 | 1.33% | 1 | 0.54% |
| Tom Lendacky | 97 | 1.23% | 3 | 1.62% |
| Octavian Purdila | 90 | 1.14% | 1 | 0.54% |
| Andy Shevchenko | 85 | 1.08% | 4 | 2.16% |
| Randy Dunlap | 76 | 0.96% | 3 | 1.62% |
| Vivek Goyal | 75 | 0.95% | 2 | 1.08% |
| Alan Cox | 67 | 0.85% | 1 | 0.54% |
| Yasuaki Ishimatsu | 53 | 0.67% | 1 | 0.54% |
| Geert Uytterhoeven | 48 | 0.61% | 1 | 0.54% |
| Fengguang Wu | 45 | 0.57% | 2 | 1.08% |
| Ivan Kokshaysky | 42 | 0.53% | 2 | 1.08% |
| Arnaldo Carvalho de Melo | 41 | 0.52% | 1 | 0.54% |
| Jérôme Glisse | 38 | 0.48% | 2 | 1.08% |
| Wei Yang | 38 | 0.48% | 3 | 1.62% |
| Ilpo Järvinen | 37 | 0.47% | 5 | 2.70% |
| Greg Kroah-Hartman | 34 | 0.43% | 3 | 1.62% |
| Mike Travis | 34 | 0.43% | 1 | 0.54% |
| Nadav Amit | 33 | 0.42% | 2 | 1.08% |
| Dave Hansen | 31 | 0.39% | 4 | 2.16% |
| Dominik Brodowski | 31 | 0.39% | 2 | 1.08% |
| Cornelia Huck | 28 | 0.35% | 1 | 0.54% |
| Art Haas | 26 | 0.33% | 1 | 0.54% |
| Ira Weiny | 26 | 0.33% | 1 | 0.54% |
| David Brownell | 18 | 0.23% | 1 | 0.54% |
| Andrew Morton | 18 | 0.23% | 3 | 1.62% |
| James Bottomley | 18 | 0.23% | 1 | 0.54% |
| Huang Shijie | 13 | 0.16% | 1 | 0.54% |
| Borislav Petkov | 13 | 0.16% | 1 | 0.54% |
| Ingo Molnar | 11 | 0.14% | 2 | 1.08% |
| Takashi Iwai | 8 | 0.10% | 1 | 0.54% |
| Thomas Gleixner | 7 | 0.09% | 3 | 1.62% |
| Simon Guinot | 6 | 0.08% | 1 | 0.54% |
| Michael S. Tsirkin | 6 | 0.08% | 1 | 0.54% |
| Chen Gong | 5 | 0.06% | 1 | 0.54% |
| Yaowei Bai | 5 | 0.06% | 1 | 0.54% |
| Denis V. Lunev | 4 | 0.05% | 1 | 0.54% |
| Nick Wilson | 4 | 0.05% | 1 | 0.54% |
| Magnus Damm | 3 | 0.04% | 1 | 0.54% |
| Miaohe Lin | 3 | 0.04% | 1 | 0.54% |
| Yasunori Goto | 2 | 0.03% | 1 | 0.54% |
| Lennert Buytenhek | 2 | 0.03% | 1 | 0.54% |
| Song Muchun | 2 | 0.03% | 1 | 0.54% |
| Alison Schofield | 2 | 0.03% | 1 | 0.54% |
| Mauro Carvalho Chehab | 1 | 0.01% | 1 | 0.54% |
| Paul Gortmaker | 1 | 0.01% | 1 | 0.54% |
| Len Brown | 1 | 0.01% | 1 | 0.54% |
| Paul Mundt | 1 | 0.01% | 1 | 0.54% |
| Rui Zhang | 1 | 0.01% | 1 | 0.54% |
| Jakub Sitnicki | 1 | 0.01% | 1 | 0.54% |
| Helge Deller | 1 | 0.01% | 1 | 0.54% |
| Adrian Bunk | 1 | 0.01% | 1 | 0.54% |
| DaeSeok Youn | 1 | 0.01% | 1 | 0.54% |
| Total | 7898 | 185 |
// SPDX-License-Identifier: GPL-2.0-only /* * 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/pseudo_fs.h> #include <linux/sched.h> #include <linux/seq_file.h> #include <linux/device.h> #include <linux/pfn.h> #include <linux/mm.h> #include <linux/mount.h> #include <linux/resource_ext.h> #include <uapi/linux/magic.h> #include <linux/string.h> #include <linux/vmalloc.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); static DEFINE_RWLOCK(resource_lock); static struct resource *next_resource(struct resource *p, bool skip_children) { if (!skip_children && p->child) return p->child; while (!p->sibling && p->parent) p = p->parent; return p->sibling; } #define for_each_resource(_root, _p, _skip_children) \ for ((_p) = (_root)->child; (_p); (_p) = next_resource(_p, _skip_children)) #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 *root = pde_data(file_inode(m->file)); struct resource *p; loff_t l = *pos; read_lock(&resource_lock); for_each_resource(root, p, false) { if (l-- == 0) break; } return p; } static void *r_next(struct seq_file *m, void *v, loff_t *pos) { struct resource *p = v; (*pos)++; return (void *)next_resource(p, false); } 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 = pde_data(file_inode(m->file)); struct resource *r = v, *p; unsigned long long start, end; 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; if (file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN)) { start = r->start; end = r->end; } else { start = end = 0; } seq_printf(m, "%*s%0*llx-%0*llx : %s\n", depth * 2, "", width, start, width, 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 __init ioresources_init(void) { proc_create_seq_data("ioports", 0, NULL, &resource_op, &ioport_resource); proc_create_seq_data("iomem", 0, NULL, &resource_op, &iomem_resource); return 0; } __initcall(ioresources_init); #endif /* CONFIG_PROC_FS */ static void free_resource(struct resource *res) { /** * If the resource was allocated using memblock early during boot * we'll leak it here: we can only return full pages back to the * buddy and trying to be smart and reusing them eventually in * alloc_resource() overcomplicates resource handling. */ if (res && PageSlab(virt_to_head_page(res))) kfree(res); } static struct resource *alloc_resource(gfp_t flags) { return kzalloc(sizeof(struct resource), flags); } /* 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, bool release_child) { struct resource *tmp, **p, *chd; p = &old->parent->child; for (;;) { tmp = *p; if (!tmp) break; if (tmp == old) { if (release_child || !(tmp->child)) { *p = tmp->sibling; } else { for (chd = tmp->child;; chd = chd->sibling) { chd->parent = tmp->parent; if (!(chd->sibling)) break; } *p = tmp->child; chd->sibling = 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, true); write_unlock(&resource_lock); return retval; } EXPORT_SYMBOL(release_resource); /** * find_next_iomem_res - Finds the lowest iomem resource that covers part of * [@start..@end]. * * If a resource is found, returns 0 and @*res is overwritten with the part * of the resource that's within [@start..@end]; if none is found, returns * -ENODEV. Returns -EINVAL for invalid parameters. * * @start: start address of the resource searched for * @end: end address of same resource * @flags: flags which the resource must have * @desc: descriptor the resource must have * @res: return ptr, if resource found * * The caller must specify @start, @end, @flags, and @desc * (which may be IORES_DESC_NONE). */ static int find_next_iomem_res(resource_size_t start, resource_size_t end, unsigned long flags, unsigned long desc, struct resource *res) { struct resource *p; if (!res) return -EINVAL; if (start >= end) return -EINVAL; read_lock(&resource_lock); for_each_resource(&iomem_resource, p, false) { /* If we passed the resource we are looking for, stop */ if (p->start > end) { p = NULL; break; } /* Skip until we find a range that matches what we look for */ if (p->end < start) continue; if ((p->flags & flags) != flags) continue; if ((desc != IORES_DESC_NONE) && (desc != p->desc)) continue; /* Found a match, break */ break; } if (p) { /* copy data */ *res = (struct resource) { .start = max(start, p->start), .end = min(end, p->end), .flags = p->flags, .desc = p->desc, .parent = p->parent, }; } read_unlock(&resource_lock); return p ? 0 : -ENODEV; } static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end, unsigned long flags, unsigned long desc, void *arg, int (*func)(struct resource *, void *)) { struct resource res; int ret = -EINVAL; while (start < end && !find_next_iomem_res(start, end, flags, desc, &res)) { ret = (*func)(&res, arg); if (ret) break; start = res.end + 1; } return ret; } /** * walk_iomem_res_desc - Walks through iomem resources and calls func() * with matching resource ranges. * * * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check. * @flags: I/O resource flags * @start: start addr * @end: end addr * @arg: function argument for the callback @func * @func: callback function that is called for each qualifying resource area * * All the memory ranges which overlap start,end and also match flags and * desc are valid candidates. * * NOTE: For a new descriptor search, define a new IORES_DESC in * <linux/ioport.h> and set it in 'desc' of a target resource entry. */ int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start, u64 end, void *arg, int (*func)(struct resource *, void *)) { return __walk_iomem_res_desc(start, end, flags, desc, arg, func); } EXPORT_SYMBOL_GPL(walk_iomem_res_desc); /* * This function calls the @func callback against all memory ranges of type * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. * Now, this function is only for System RAM, it deals with full ranges and * not PFNs. If resources are not PFN-aligned, dealing with PFNs can truncate * ranges. */ int walk_system_ram_res(u64 start, u64 end, void *arg, int (*func)(struct resource *, void *)) { unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, arg, func); } /* * This function, being a variant of walk_system_ram_res(), calls the @func * callback against all memory ranges of type System RAM which are marked as * IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY in reversed order, i.e., from * higher to lower. */ int walk_system_ram_res_rev(u64 start, u64 end, void *arg, int (*func)(struct resource *, void *)) { struct resource res, *rams; int rams_size = 16, i; unsigned long flags; int ret = -1; /* create a list */ rams = kvcalloc(rams_size, sizeof(struct resource), GFP_KERNEL); if (!rams) return ret; flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; i = 0; while ((start < end) && (!find_next_iomem_res(start, end, flags, IORES_DESC_NONE, &res))) { if (i >= rams_size) { /* re-alloc */ struct resource *rams_new; rams_new = kvrealloc(rams, rams_size * sizeof(struct resource), (rams_size + 16) * sizeof(struct resource), GFP_KERNEL); if (!rams_new) goto out; rams = rams_new; rams_size += 16; } rams[i].start = res.start; rams[i++].end = res.end; start = res.end + 1; } /* go reverse */ for (i--; i >= 0; i--) { ret = (*func)(&rams[i], arg); if (ret) break; } out: kvfree(rams); return ret; } /* * This function calls the @func callback against all memory ranges, which * are ranges marked as IORESOURCE_MEM and IORESOUCE_BUSY. */ int walk_mem_res(u64 start, u64 end, void *arg, int (*func)(struct resource *, void *)) { unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY; return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, arg, func); } /* * This function calls the @func callback against all memory ranges of type * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. * It is to be used 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 *)) { resource_size_t start, end; unsigned long flags; struct resource res; unsigned long pfn, end_pfn; int ret = -EINVAL; start = (u64) start_pfn << PAGE_SHIFT; end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; while (start < end && !find_next_iomem_res(start, end, flags, IORES_DESC_NONE, &res)) { pfn = PFN_UP(res.start); end_pfn = PFN_DOWN(res.end + 1); if (end_pfn > pfn) ret = (*func)(pfn, end_pfn - pfn, arg); if (ret) break; start = res.end + 1; } return ret; } 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; } EXPORT_SYMBOL_GPL(page_is_ram); static int __region_intersects(struct resource *parent, resource_size_t start, size_t size, unsigned long flags, unsigned long desc) { struct resource res; int type = 0; int other = 0; struct resource *p; res.start = start; res.end = start + size - 1; for (p = parent->child; p ; p = p->sibling) { bool is_type = (((p->flags & flags) == flags) && ((desc == IORES_DESC_NONE) || (desc == p->desc))); if (resource_overlaps(p, &res)) is_type ? type++ : other++; } if (type == 0) return REGION_DISJOINT; if (other == 0) return REGION_INTERSECTS; return REGION_MIXED; } /** * region_intersects() - determine intersection of region with known resources * @start: region start address * @size: size of region * @flags: flags of resource (in iomem_resource) * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE * * Check if the specified region partially overlaps or fully eclipses a * resource identified by @flags and @desc (optional with IORES_DESC_NONE). * Return REGION_DISJOINT if the region does not overlap @flags/@desc, * return REGION_MIXED if the region overlaps @flags/@desc and another * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc * and no other defined resource. Note that REGION_INTERSECTS is also * returned in the case when the specified region overlaps RAM and undefined * memory holes. * * region_intersect() is used by memory remapping functions to ensure * the user is not remapping RAM and is a vast speed up over walking * through the resource table page by page. */ int region_intersects(resource_size_t start, size_t size, unsigned long flags, unsigned long desc) { int ret; read_lock(&resource_lock); ret = __region_intersects(&iomem_resource, start, size, flags, desc); read_unlock(&resource_lock); return ret; } EXPORT_SYMBOL_GPL(region_intersects); void __weak arch_remove_reservations(struct resource *avail) { } 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; } /* * Find empty space in the resource tree with the given range and * alignment constraints */ static int __find_resource_space(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; resource_alignf alignf = constraint->alignf; 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.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; if (alignf) { alloc.start = alignf(constraint->alignf_data, &avail, size, constraint->align); } else { alloc.start = avail.start; } 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_resource_space - Find empty space in the resource tree * @root: Root resource descriptor * @new: Resource descriptor awaiting an empty resource space * @size: The minimum size of the empty space * @constraint: The range and alignment constraints to be met * * Finds an empty space under @root in the resource tree satisfying range and * alignment @constraints. * * Return: * * %0 - if successful, @new members start, end, and flags are altered. * * %-EBUSY - if no empty space was found. */ int find_resource_space(struct resource *root, struct resource *new, resource_size_t size, struct resource_constraint *constraint) { return __find_resource_space(root, NULL, new, size, constraint); } EXPORT_SYMBOL_GPL(find_resource_space); /** * 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_space(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_alignf alignf, void *alignf_data) { int err; struct resource_constraint constraint; 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_space(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; pr_info("Expanded resource %s due to conflict with %s\n", new->name, conflict->name); } write_unlock(&resource_lock); } /* * Not for general consumption, only early boot memory map parsing, PCI * resource discovery, and late discovery of CXL resources are expected * to use this interface. The former are built-in and only the latter, * CXL, is a module. */ EXPORT_SYMBOL_NS_GPL(insert_resource_expand_to_fit, CXL); /** * 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); pr_warn("Trying to free nonexistent resource <%pa-%pa>\n", &start, &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; } 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) { resource_size_t end = addr + size - 1; struct resource *p; int err = 0; read_lock(&resource_lock); for_each_resource(&iomem_resource, p, false) { /* * We can probably skip the resources without * IORESOURCE_IO attribute? */ if (p->start > end) continue; if (p->end < addr) continue; if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && PFN_DOWN(p->end) >= PFN_DOWN(end)) 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; pr_warn("resource sanity check: requesting [mem %pa-%pa], which spans more than %s %pR\n", &addr, &end, 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 exclusive to the kernel and must not be mapped to * user space, for example, via /dev/mem. * * Returns true if exclusive to the kernel, otherwise returns false. */ bool resource_is_exclusive(struct resource *root, u64 addr, resource_size_t size) { const unsigned int exclusive_system_ram = IORESOURCE_SYSTEM_RAM | IORESOURCE_EXCLUSIVE; bool skip_children = false, err = false; struct resource *p; read_lock(&resource_lock); for_each_resource(root, p, skip_children) { if (p->start >= addr + size) break; if (p->end < addr) { skip_children = true; continue; } skip_children = false; /* * IORESOURCE_SYSTEM_RAM resources are exclusive if * IORESOURCE_EXCLUSIVE is set, even if they * are not busy and even if "iomem=relaxed" is set. The * responsible driver dynamically adds/removes system RAM within * such an area and uncontrolled access is dangerous. */ if ((p->flags & exclusive_system_ram) == exclusive_system_ram) { err = true; break; } /* * A resource is exclusive if IORESOURCE_EXCLUSIVE is set * or CONFIG_IO_STRICT_DEVMEM is enabled and the * resource is busy. */ if (!strict_iomem_checks || !(p->flags & IORESOURCE_BUSY)) continue; if (IS_ENABLED(CONFIG_IO_STRICT_DEVMEM) || p->flags & IORESOURCE_EXCLUSIVE) { err = true; break; } } read_unlock(&resource_lock); return err; } bool iomem_is_exclusive(u64 addr) { return resource_is_exclusive(&iomem_resource, addr & PAGE_MASK, PAGE_SIZE); } 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_GET_FREE_REGION #define GFR_DESCENDING (1UL << 0) #define GFR_REQUEST_REGION (1UL << 1) #define GFR_DEFAULT_ALIGN (1UL << PA_SECTION_SHIFT) static resource_size_t gfr_start(struct resource *base, resource_size_t size, resource_size_t align, unsigned long flags) { if (flags & GFR_DESCENDING) { resource_size_t end; end = min_t(resource_size_t, base->end, PHYSMEM_END); return end - size + 1; } return ALIGN(base->start, align); } static bool gfr_continue(struct resource *base, resource_size_t addr, resource_size_t size, unsigned long flags) { if (flags & GFR_DESCENDING) return addr > size && addr >= base->start; /* * In the ascend case be careful that the last increment by * @size did not wrap 0. */ return addr > addr - size && addr <= min_t(resource_size_t, base->end, PHYSMEM_END); } static resource_size_t gfr_next(resource_size_t addr, resource_size_t size, unsigned long flags) { if (flags & GFR_DESCENDING) return addr - size; return addr + size; } static void remove_free_mem_region(void *_res) { struct resource *res = _res; if (res->parent) remove_resource(res); free_resource(res); } static struct resource * get_free_mem_region(struct device *dev, struct resource *base, resource_size_t size, const unsigned long align, const char *name, const unsigned long desc, const unsigned long flags) { resource_size_t addr; struct resource *res; struct region_devres *dr = NULL; size = ALIGN(size, align); res = alloc_resource(GFP_KERNEL); if (!res) return ERR_PTR(-ENOMEM); if (dev && (flags & GFR_REQUEST_REGION)) { dr = devres_alloc(devm_region_release, sizeof(struct region_devres), GFP_KERNEL); if (!dr) { free_resource(res); return ERR_PTR(-ENOMEM); } } else if (dev) { if (devm_add_action_or_reset(dev, remove_free_mem_region, res)) return ERR_PTR(-ENOMEM); } write_lock(&resource_lock); for (addr = gfr_start(base, size, align, flags); gfr_continue(base, addr, align, flags); addr = gfr_next(addr, align, flags)) { if (__region_intersects(base, addr, size, 0, IORES_DESC_NONE) != REGION_DISJOINT) continue; if (flags & GFR_REQUEST_REGION) { 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 = desc; write_unlock(&resource_lock); /* * A driver is claiming this region so revoke any * mappings. */ revoke_iomem(res); } else { res->start = addr; res->end = addr + size - 1; res->name = name; res->desc = desc; res->flags = IORESOURCE_MEM; /* * Only succeed if the resource hosts an exclusive * range after the insert */ if (__insert_resource(base, res) || res->child) break; write_unlock(&resource_lock); } return res; } write_unlock(&resource_lock); if (flags & GFR_REQUEST_REGION) { free_resource(res); devres_free(dr); } else if (dev) devm_release_action(dev, remove_free_mem_region, res); 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) { unsigned long flags = GFR_DESCENDING | GFR_REQUEST_REGION; return get_free_mem_region(dev, base, size, GFR_DEFAULT_ALIGN, dev_name(dev), IORES_DESC_DEVICE_PRIVATE_MEMORY, flags); } EXPORT_SYMBOL_GPL(devm_request_free_mem_region); struct resource *request_free_mem_region(struct resource *base, unsigned long size, const char *name) { unsigned long flags = GFR_DESCENDING | GFR_REQUEST_REGION; return get_free_mem_region(NULL, base, size, GFR_DEFAULT_ALIGN, name, IORES_DESC_DEVICE_PRIVATE_MEMORY, flags); } EXPORT_SYMBOL_GPL(request_free_mem_region); /** * alloc_free_mem_region - find a free region relative to @base * @base: resource that will parent the new resource * @size: size in bytes of memory to allocate from @base * @align: alignment requirements for the allocation * @name: resource name * * Buses like CXL, that can dynamically instantiate new memory regions, * need a method to allocate physical address space for those regions. * Allocate and insert a new resource to cover a free, unclaimed by a * descendant of @base, range in the span of @base. */ struct resource *alloc_free_mem_region(struct resource *base, unsigned long size, unsigned long align, const char *name) { /* Default of ascending direction and insert resource */ unsigned long flags = 0; return get_free_mem_region(NULL, base, size, align, name, IORES_DESC_NONE, flags); } EXPORT_SYMBOL_NS_GPL(alloc_free_mem_region, CXL); #endif /* CONFIG_GET_FREE_REGION */ 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);
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