litmus-rt-budgetable-locks.git/.git - Unnamed repository; edit this file 'description' to name the repository.

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author	Al Viro <viro@zeniv.linux.org.uk>	2016-07-29 17:45:21 -0400
committer	Al Viro <viro@zeniv.linux.org.uk>	2016-07-29 17:45:21 -0400
commit	15d3c589f6305c50a705572dbb33620c5cba416c (patch)
tree	77388e7718be7a81d9e83983b535768df552986f
parent	d614146d18159e54d4dfc289e4c1534ccc485cf2 (diff)

fold _d_rehash() and __d_rehash() together

The only place where we feed to __d_rehash() something other than d_hash(dentry->d_name.hash) is __d_move(), where we give it d_hash of another dentry. Postpone rehashing until we'd switched the names and we are rid of that exception, along with the need to keep _d_rehash() and __d_rehash() separate. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Diffstat

-rw-r--r--

fs/dcache.c

1 files changed, 11 insertions, 23 deletions

 }
 EXPORT_SYMBOL(d_delete);
-static void __d_rehash(struct dentry * entry, struct hlist_bl_head *b)
+static void __d_rehash(struct dentry *entry)
 {
+        struct hlist_bl_head *b = d_hash(entry->d_name.hash);
         BUG_ON(!d_unhashed(entry));
         hlist_bl_lock(b);
         hlist_bl_add_head_rcu(&entry->d_hash, b);
         hlist_bl_unlock(b);
 }
-static void _d_rehash(struct dentry * entry)
-{
-        __d_rehash(entry, d_hash(entry->d_name.hash));
-}
 /**
  * d_rehash     - add an entry back to the hash
  * @entry: dentry to add to the hash
 void d_rehash(struct dentry * entry)
 {
         spin_lock(&entry->d_lock);
-        _d_rehash(entry);
+        __d_rehash(entry);
         spin_unlock(&entry->d_lock);
 }
 EXPORT_SYMBOL(d_rehash);
                 raw_write_seqcount_end(&dentry->d_seq);
                 fsnotify_update_flags(dentry);
         }
-        _d_rehash(dentry);
+        __d_rehash(dentry);
         if (dir)
                 end_dir_add(dir, n);
         spin_unlock(&dentry->d_lock);
                         alias = NULL;
                 } else {
                         __dget_dlock(alias);
-                        _d_rehash(alias);
+                        __d_rehash(alias);
                         spin_unlock(&alias->d_lock);
                 }
                 spin_unlock(&inode->i_lock);
         write_seqcount_begin(&dentry->d_seq);
         write_seqcount_begin_nested(&target->d_seq, DENTRY_D_LOCK_NESTED);
+        /* unhash both */
         /* __d_drop does write_seqcount_barrier, but they're OK to nest. */
-        /*
-         * Move the dentry to the target hash queue. Don't bother checking
-         * for the same hash queue because of how unlikely it is.
-         */
         __d_drop(dentry);
-        __d_rehash(dentry, d_hash(target->d_name.hash));
-        /*
-         * Unhash the target (d_delete() is not usable here).  If exchanging
-         * the two dentries, then rehash onto the other's hash queue.
-         */
         __d_drop(target);
-        if (exchange) {
-                __d_rehash(target, d_hash(dentry->d_name.hash));
-        }
         /* Switch the names.. */
         if (exchange)
         else
                 copy_name(dentry, target);
+        /* rehash in new place(s) */
+        __d_rehash(dentry);
+        if (exchange)
+                __d_rehash(target);
         /* ... and switch them in the tree */
         if (IS_ROOT(dentry)) {
                 /* splicing a tree */

/* * 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; old->end = new.end; } else { __release_resource(old); *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. */ 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. */ int insert_resource(struct resource *parent, struct resource *new) { struct resource *conflict; conflict = insert_resource_conflict(parent, new); return conflict ? -EBUSY : 0; } /** * 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); } /** * 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) { struct resource *tmp, *parent = res->parent; resource_size_t end = start + size - 1; int result = -EBUSY; write_lock(&resource_lock); 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: 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 = kzalloc(sizeof(*res), GFP_ATOMIC); struct resource *next_res = NULL; if (!res) return; res->name = name; res->start = start; res->end = end; res->flags = IORESOURCE_BUSY; 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) { kfree(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 = kzalloc(sizeof(*next_res), GFP_ATOMIC); if (!next_res) { kfree(res); break; } next_res->name = name; next_res->start = conflict->end + 1; next_res->end = end; next_res->flags = IORESOURCE_BUSY; } } 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. * * check_region returns non-zero if the area is already busy. * * release_region releases a matching busy region. */ static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait); /** * __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) { DECLARE_WAITQUEUE(wait, current); struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL); if (!res) return NULL; res->name = name; res->start = start; res->end = start + n - 1; res->flags = IORESOURCE_BUSY; res->flags |= flags; write_lock(&resource_lock); for (;;) { struct resource *conflict; conflict = __request_resource(parent, res); if (!conflict) break; if (conflict != parent) { parent = conflict; if (!(conflict->flags & IORESOURCE_BUSY)) 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.. */ kfree(res); res = NULL; break; } write_unlock(&resource_lock); return res; } EXPORT_SYMBOL(__request_region); /** * __check_region - check if a resource region is busy or free * @parent: parent resource descriptor * @start: resource start address * @n: resource region size * * Returns 0 if the region is free at the moment it is checked, * returns %-EBUSY if the region is busy. * * NOTE: * This function is deprecated because its use is racy. * Even if it returns 0, a subsequent call to request_region() * may fail because another driver etc. just allocated the region. * Do NOT use it. It will be removed from the kernel. */ int __check_region(struct resource *parent, resource_size_t start, resource_size_t n) { struct resource * res; res = __request_region(parent, start, n, "check-region", 0); if (!res) return -EBUSY; release_resource(res); kfree(res); return 0; } EXPORT_SYMBOL(__check_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); kfree(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); /* * Managed region 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); /* * Called from init/main.c to reserve IO ports. */ #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; if (get_option (&str, &io_start) != 2) break; if (get_option (&str, &io_num) == 0) break; if (x < MAXRESERVE) { struct resource *res = reserve + x; res->name = "reserved"; res->start = io_start; res->end = io_start + io_num - 1; res->flags = IORESOURCE_BUSY; res->child = NULL; if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, 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 map sanity check conflict: " "0x%llx 0x%llx 0x%llx 0x%llx %s\n", (unsigned long long)addr, (unsigned long long)(addr + size - 1), (unsigned long long)p->start, (unsigned long long)p->end, p->name); 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 1 if reserved, 0 if not reserved. */ int iomem_is_exclusive(u64 addr) { struct resource *p = &iomem_resource; int err = 0; loff_t l; int size = PAGE_SIZE; if (!strict_iomem_checks) return 0; 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; if (p->flags & IORESOURCE_BUSY && p->flags & IORESOURCE_EXCLUSIVE) { err = 1; break; } } read_unlock(&resource_lock); return err; } 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; } __setup("iomem=", strict_iomem);


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