The struct resource uses singly linked list to link siblings. It's not easy to do reverse iteration on sibling list. So replace it with list_head.
And this makes codes in kernel/resource.c more readable after refactoring than pointer operation. Besides, type of member variables of struct resource, sibling and child, are changed from 'struct resource *' to 'struct list_head'. This brings two pointers of size increase. Suggested-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Baoquan He <b...@redhat.com> Cc: Patrik Jakobsson <patrik.r.jakobs...@gmail.com> Cc: David Airlie <airl...@linux.ie> Cc: "K. Y. Srinivasan" <k...@microsoft.com> Cc: Haiyang Zhang <haiya...@microsoft.com> Cc: Stephen Hemminger <sthem...@microsoft.com> Cc: Dmitry Torokhov <dmitry.torok...@gmail.com> Cc: Dan Williams <dan.j.willi...@intel.com> Cc: Rob Herring <robh...@kernel.org> Cc: Frank Rowand <frowand.l...@gmail.com> Cc: Keith Busch <keith.bu...@intel.com> Cc: Jonathan Derrick <jonathan.derr...@intel.com> Cc: Lorenzo Pieralisi <lorenzo.pieral...@arm.com> Cc: Bjorn Helgaas <bhelg...@google.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Brijesh Singh <brijesh.si...@amd.com> Cc: "Jérôme Glisse" <jgli...@redhat.com> Cc: Borislav Petkov <b...@suse.de> Cc: Tom Lendacky <thomas.lenda...@amd.com> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> Cc: Yaowei Bai <baiyao...@cmss.chinamobile.com> Cc: Wei Yang <richard.weiy...@gmail.com> Cc: de...@linuxdriverproject.org Cc: linux-in...@vger.kernel.org Cc: linux-nvdimm@lists.01.org Cc: devicet...@vger.kernel.org Cc: linux-...@vger.kernel.org --- v2->v3: Rename resource functions first_child() and sibling() to resource_first_chils() and resource_sibling(). Dan suggested this. Move resource_first_chils() and resource_sibling() to linux/ioport.h and make them as inline function. Rob suggested this. Accordingly add linux/list.h including in linux/ioport.h, please help review if this bring efficiency degradation or code redundancy. The change on struct resource {} bring two pointers of size increase, mention this in git log to make it more specifically, Rob suggested this. arch/sparc/kernel/ioport.c | 2 +- drivers/gpu/drm/drm_memory.c | 3 +- drivers/gpu/drm/gma500/gtt.c | 5 +- drivers/hv/vmbus_drv.c | 52 ++++---- drivers/input/joystick/iforce/iforce-main.c | 4 +- drivers/nvdimm/e820.c | 2 +- drivers/nvdimm/namespace_devs.c | 6 +- drivers/nvdimm/nd.h | 5 +- drivers/of/address.c | 4 +- drivers/parisc/lba_pci.c | 4 +- drivers/pci/host/vmd.c | 8 +- drivers/pci/probe.c | 2 + drivers/pci/setup-bus.c | 2 +- include/linux/ioport.h | 17 ++- kernel/resource.c | 181 +++++++++++++--------------- 15 files changed, 148 insertions(+), 149 deletions(-) diff --git a/arch/sparc/kernel/ioport.c b/arch/sparc/kernel/ioport.c index 3bcef9ce74df..4e91fbbbedcc 100644 --- a/arch/sparc/kernel/ioport.c +++ b/arch/sparc/kernel/ioport.c @@ -669,7 +669,7 @@ static int sparc_io_proc_show(struct seq_file *m, void *v) struct resource *root = m->private, *r; const char *nm; - for (r = root->child; r != NULL; r = r->sibling) { + list_for_each_entry(r, &root->child, sibling) { if ((nm = r->name) == NULL) nm = "???"; seq_printf(m, "%016llx-%016llx: %s\n", (unsigned long long)r->start, diff --git a/drivers/gpu/drm/drm_memory.c b/drivers/gpu/drm/drm_memory.c index 3c54044214db..53e300a993dc 100644 --- a/drivers/gpu/drm/drm_memory.c +++ b/drivers/gpu/drm/drm_memory.c @@ -155,9 +155,8 @@ u64 drm_get_max_iomem(void) struct resource *tmp; resource_size_t max_iomem = 0; - for (tmp = iomem_resource.child; tmp; tmp = tmp->sibling) { + list_for_each_entry(tmp, &iomem_resource.child, sibling) max_iomem = max(max_iomem, tmp->end); - } return max_iomem; } diff --git a/drivers/gpu/drm/gma500/gtt.c b/drivers/gpu/drm/gma500/gtt.c index 3949b0990916..addd3bc009af 100644 --- a/drivers/gpu/drm/gma500/gtt.c +++ b/drivers/gpu/drm/gma500/gtt.c @@ -565,7 +565,7 @@ int psb_gtt_init(struct drm_device *dev, int resume) int psb_gtt_restore(struct drm_device *dev) { struct drm_psb_private *dev_priv = dev->dev_private; - struct resource *r = dev_priv->gtt_mem->child; + struct resource *r; struct gtt_range *range; unsigned int restored = 0, total = 0, size = 0; @@ -573,14 +573,13 @@ int psb_gtt_restore(struct drm_device *dev) mutex_lock(&dev_priv->gtt_mutex); psb_gtt_init(dev, 1); - while (r != NULL) { + list_for_each_entry(r, &dev_priv->gtt_mem->child, sibling) { range = container_of(r, struct gtt_range, resource); if (range->pages) { psb_gtt_insert(dev, range, 1); size += range->resource.end - range->resource.start; restored++; } - r = r->sibling; total++; } mutex_unlock(&dev_priv->gtt_mutex); diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index b10fe26c4891..d87ec5a1bc4c 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1412,9 +1412,8 @@ static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx) { resource_size_t start = 0; resource_size_t end = 0; - struct resource *new_res; + struct resource *new_res, *tmp; struct resource **old_res = &hyperv_mmio; - struct resource **prev_res = NULL; switch (res->type) { @@ -1461,44 +1460,36 @@ static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx) /* * If two ranges are adjacent, merge them. */ - do { - if (!*old_res) { - *old_res = new_res; - break; - } - - if (((*old_res)->end + 1) == new_res->start) { - (*old_res)->end = new_res->end; + if (!*old_res) { + *old_res = new_res; + return AE_OK; + } + tmp = *old_res; + list_for_each_entry_from(tmp, &tmp->parent->child, sibling) { + if ((tmp->end + 1) == new_res->start) { + tmp->end = new_res->end; kfree(new_res); break; } - if ((*old_res)->start == new_res->end + 1) { - (*old_res)->start = new_res->start; + if (tmp->start == new_res->end + 1) { + tmp->start = new_res->start; kfree(new_res); break; } - if ((*old_res)->start > new_res->end) { - new_res->sibling = *old_res; - if (prev_res) - (*prev_res)->sibling = new_res; - *old_res = new_res; + if (tmp->start > new_res->end) { + list_add(&new_res->sibling, tmp->sibling.prev); break; } - - prev_res = old_res; - old_res = &(*old_res)->sibling; - - } while (1); + } return AE_OK; } static int vmbus_acpi_remove(struct acpi_device *device) { - struct resource *cur_res; - struct resource *next_res; + struct resource *res; if (hyperv_mmio) { if (fb_mmio) { @@ -1507,10 +1498,9 @@ static int vmbus_acpi_remove(struct acpi_device *device) fb_mmio = NULL; } - for (cur_res = hyperv_mmio; cur_res; cur_res = next_res) { - next_res = cur_res->sibling; - kfree(cur_res); - } + res = hyperv_mmio; + list_for_each_entry_from(res, &res->parent->child, sibling) + kfree(res); } return 0; @@ -1596,7 +1586,8 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj, } } - for (iter = hyperv_mmio; iter; iter = iter->sibling) { + iter = hyperv_mmio; + list_for_each_entry_from(iter, &iter->parent->child, sibling) { if ((iter->start >= max) || (iter->end <= min)) continue; @@ -1639,7 +1630,8 @@ void vmbus_free_mmio(resource_size_t start, resource_size_t size) struct resource *iter; down(&hyperv_mmio_lock); - for (iter = hyperv_mmio; iter; iter = iter->sibling) { + iter = hyperv_mmio; + list_for_each_entry_from(iter, &iter->parent->child, sibling) { if ((iter->start >= start + size) || (iter->end <= start)) continue; diff --git a/drivers/input/joystick/iforce/iforce-main.c b/drivers/input/joystick/iforce/iforce-main.c index daeeb4c7e3b0..5c0be27b33ff 100644 --- a/drivers/input/joystick/iforce/iforce-main.c +++ b/drivers/input/joystick/iforce/iforce-main.c @@ -305,8 +305,8 @@ int iforce_init_device(struct iforce *iforce) iforce->device_memory.end = 200; iforce->device_memory.flags = IORESOURCE_MEM; iforce->device_memory.parent = NULL; - iforce->device_memory.child = NULL; - iforce->device_memory.sibling = NULL; + INIT_LIST_HEAD(&iforce->device_memory.child); + INIT_LIST_HEAD(&iforce->device_memory.sibling); /* * Wait until device ready - until it sends its first response. diff --git a/drivers/nvdimm/e820.c b/drivers/nvdimm/e820.c index 6f9a6ffd7cde..513e661bb0d8 100644 --- a/drivers/nvdimm/e820.c +++ b/drivers/nvdimm/e820.c @@ -53,7 +53,7 @@ static int e820_pmem_probe(struct platform_device *pdev) goto err; platform_set_drvdata(pdev, nvdimm_bus); - for (p = iomem_resource.child; p ; p = p->sibling) { + list_for_each_entry(p, &iomem_resource.child, sibling) { struct nd_region_desc ndr_desc; if (p->desc != IORES_DESC_PERSISTENT_MEMORY_LEGACY) diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c index 28afdd668905..f53d410d9981 100644 --- a/drivers/nvdimm/namespace_devs.c +++ b/drivers/nvdimm/namespace_devs.c @@ -637,7 +637,7 @@ static resource_size_t scan_allocate(struct nd_region *nd_region, retry: first = 0; for_each_dpa_resource(ndd, res) { - struct resource *next = res->sibling, *new_res = NULL; + struct resource *next = resource_sibling(res), *new_res = NULL; resource_size_t allocate, available = 0; enum alloc_loc loc = ALLOC_ERR; const char *action; @@ -763,7 +763,7 @@ static resource_size_t scan_allocate(struct nd_region *nd_region, * an initial "pmem-reserve pass". Only do an initial BLK allocation * when none of the DPA space is reserved. */ - if ((is_pmem || !ndd->dpa.child) && n == to_allocate) + if ((is_pmem || list_empty(&ndd->dpa.child)) && n == to_allocate) return init_dpa_allocation(label_id, nd_region, nd_mapping, n); return n; } @@ -779,7 +779,7 @@ static int merge_dpa(struct nd_region *nd_region, retry: for_each_dpa_resource(ndd, res) { int rc; - struct resource *next = res->sibling; + struct resource *next = resource_sibling(res); resource_size_t end = res->start + resource_size(res); if (!next || strcmp(res->name, label_id->id) != 0 diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index 32e0364b48b9..da7da15e03e7 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -102,11 +102,10 @@ unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd); (unsigned long long) (res ? res->start : 0), ##arg) #define for_each_dpa_resource(ndd, res) \ - for (res = (ndd)->dpa.child; res; res = res->sibling) + list_for_each_entry(res, &(ndd)->dpa.child, sibling) #define for_each_dpa_resource_safe(ndd, res, next) \ - for (res = (ndd)->dpa.child, next = res ? res->sibling : NULL; \ - res; res = next, next = next ? next->sibling : NULL) + list_for_each_entry_safe(res, next, &(ndd)->dpa.child, sibling) struct nd_percpu_lane { int count; diff --git a/drivers/of/address.c b/drivers/of/address.c index 53349912ac75..e2e25719ab52 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -330,7 +330,9 @@ int of_pci_range_to_resource(struct of_pci_range *range, { int err; res->flags = range->flags; - res->parent = res->child = res->sibling = NULL; + res->parent = NULL; + INIT_LIST_HEAD(&res->child); + INIT_LIST_HEAD(&res->sibling); res->name = np->full_name; if (res->flags & IORESOURCE_IO) { diff --git a/drivers/parisc/lba_pci.c b/drivers/parisc/lba_pci.c index 69bd98421eb1..7482bdfd1959 100644 --- a/drivers/parisc/lba_pci.c +++ b/drivers/parisc/lba_pci.c @@ -170,8 +170,8 @@ lba_dump_res(struct resource *r, int d) for (i = d; i ; --i) printk(" "); printk(KERN_DEBUG "%p [%lx,%lx]/%lx\n", r, (long)r->start, (long)r->end, r->flags); - lba_dump_res(r->child, d+2); - lba_dump_res(r->sibling, d); + lba_dump_res(resource_first_child(&r->child), d+2); + lba_dump_res(resource_sibling(r), d); } diff --git a/drivers/pci/host/vmd.c b/drivers/pci/host/vmd.c index 930a8fa08bd6..c3000af903ea 100644 --- a/drivers/pci/host/vmd.c +++ b/drivers/pci/host/vmd.c @@ -520,14 +520,14 @@ static struct pci_ops vmd_ops = { static void vmd_attach_resources(struct vmd_dev *vmd) { - vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1]; - vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2]; + list_add(&vmd->resources[1].sibling, &vmd->dev->resource[VMD_MEMBAR1].child); + list_add(&vmd->resources[2].sibling, &vmd->dev->resource[VMD_MEMBAR2].child); } static void vmd_detach_resources(struct vmd_dev *vmd) { - vmd->dev->resource[VMD_MEMBAR1].child = NULL; - vmd->dev->resource[VMD_MEMBAR2].child = NULL; + INIT_LIST_HEAD(&vmd->dev->resource[VMD_MEMBAR1].child); + INIT_LIST_HEAD(&vmd->dev->resource[VMD_MEMBAR2].child); } /* diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index ac91b6fd0bcd..d162c77bec29 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -59,6 +59,8 @@ static struct resource *get_pci_domain_busn_res(int domain_nr) r->res.start = 0; r->res.end = 0xff; r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED; + INIT_LIST_HEAD(&r->res.child); + INIT_LIST_HEAD(&r->res.sibling); list_add_tail(&r->list, &pci_domain_busn_res_list); diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 072784f55ea5..0d5e30004ca6 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -2107,7 +2107,7 @@ int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type) continue; /* Ignore BARs which are still in use */ - if (res->child) + if (!list_empty(&res->child)) continue; ret = add_to_list(&saved, bridge, res, 0, 0); diff --git a/include/linux/ioport.h b/include/linux/ioport.h index da0ebaec25f0..225d13d3500a 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -12,6 +12,7 @@ #ifndef __ASSEMBLY__ #include <linux/compiler.h> #include <linux/types.h> +#include <linux/list.h> /* * Resources are tree-like, allowing * nesting etc.. @@ -22,7 +23,8 @@ struct resource { const char *name; unsigned long flags; unsigned long desc; - struct resource *parent, *sibling, *child; + struct list_head child, sibling; + struct resource *parent; }; /* @@ -215,7 +217,6 @@ static inline bool resource_contains(struct resource *r1, struct resource *r2) return r1->start <= r2->start && r1->end >= r2->end; } - /* Convenience shorthand with allocation */ #define request_region(start,n,name) __request_region(&ioport_resource, (start), (n), (name), 0) #define request_muxed_region(start,n,name) __request_region(&ioport_resource, (start), (n), (name), IORESOURCE_MUXED) @@ -286,6 +287,18 @@ static inline bool resource_overlaps(struct resource *r1, struct resource *r2) return (r1->start <= r2->end && r1->end >= r2->start); } +static inline struct resource *resource_sibling(struct resource *res) +{ + if (res->parent && !list_is_last(&res->sibling, &res->parent->child)) + return list_next_entry(res, sibling); + return NULL; +} + +static inline struct resource *resource_first_child(struct list_head *head) +{ + return list_first_entry_or_null(head, struct resource, sibling); +} + #endif /* __ASSEMBLY__ */ #endif /* _LINUX_IOPORT_H */ diff --git a/kernel/resource.c b/kernel/resource.c index 2af6c03858b9..4f560991c130 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -31,6 +31,8 @@ struct resource ioport_resource = { .start = 0, .end = IO_SPACE_LIMIT, .flags = IORESOURCE_IO, + .sibling = LIST_HEAD_INIT(ioport_resource.sibling), + .child = LIST_HEAD_INIT(ioport_resource.child), }; EXPORT_SYMBOL(ioport_resource); @@ -39,6 +41,8 @@ struct resource iomem_resource = { .start = 0, .end = -1, .flags = IORESOURCE_MEM, + .sibling = LIST_HEAD_INIT(iomem_resource.sibling), + .child = LIST_HEAD_INIT(iomem_resource.child), }; EXPORT_SYMBOL(iomem_resource); @@ -57,20 +61,20 @@ static DEFINE_RWLOCK(resource_lock); * by boot mem after the system is up. So for reusing the resource entry * we need to remember the resource. */ -static struct resource *bootmem_resource_free; +static struct list_head bootmem_resource_free = LIST_HEAD_INIT(bootmem_resource_free); static DEFINE_SPINLOCK(bootmem_resource_lock); static struct resource *next_resource(struct resource *p, bool sibling_only) { /* Caller wants to traverse through siblings only */ if (sibling_only) - return p->sibling; + return resource_sibling(p); - if (p->child) - return p->child; - while (!p->sibling && p->parent) + if (!list_empty(&p->child)) + return resource_first_child(&p->child); + while (!resource_sibling(p) && p->parent) p = p->parent; - return p->sibling; + return resource_sibling(p); } static void *r_next(struct seq_file *m, void *v, loff_t *pos) @@ -90,7 +94,7 @@ static void *r_start(struct seq_file *m, loff_t *pos) 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)) + for (p = resource_first_child(&p->child); p && l < *pos; p = r_next(m, p, &l)) ; return p; } @@ -186,8 +190,7 @@ static void free_resource(struct resource *res) if (!PageSlab(virt_to_head_page(res))) { spin_lock(&bootmem_resource_lock); - res->sibling = bootmem_resource_free; - bootmem_resource_free = res; + list_add(&res->sibling, &bootmem_resource_free); spin_unlock(&bootmem_resource_lock); } else { kfree(res); @@ -199,10 +202,9 @@ static struct resource *alloc_resource(gfp_t flags) struct resource *res = NULL; spin_lock(&bootmem_resource_lock); - if (bootmem_resource_free) { - res = bootmem_resource_free; - bootmem_resource_free = res->sibling; - } + res = resource_first_child(&bootmem_resource_free); + if (res) + list_del(&res->sibling); spin_unlock(&bootmem_resource_lock); if (res) @@ -210,6 +212,8 @@ static struct resource *alloc_resource(gfp_t flags) else res = kzalloc(sizeof(struct resource), flags); + INIT_LIST_HEAD(&res->child); + INIT_LIST_HEAD(&res->sibling); return res; } @@ -218,7 +222,7 @@ static struct resource * __request_resource(struct resource *root, struct resour { resource_size_t start = new->start; resource_size_t end = new->end; - struct resource *tmp, **p; + struct resource *tmp; if (end < start) return root; @@ -226,64 +230,62 @@ static struct resource * __request_resource(struct resource *root, struct resour return root; if (end > root->end) return root; - p = &root->child; - for (;;) { - tmp = *p; - if (!tmp || tmp->start > end) { - new->sibling = tmp; - *p = new; + + if (list_empty(&root->child)) { + list_add(&new->sibling, &root->child); + new->parent = root; + INIT_LIST_HEAD(&new->child); + return NULL; + } + + list_for_each_entry(tmp, &root->child, sibling) { + if (tmp->start > end) { + list_add(&new->sibling, tmp->sibling.prev); new->parent = root; + INIT_LIST_HEAD(&new->child); return NULL; } - p = &tmp->sibling; if (tmp->end < start) continue; return tmp; } + + list_add_tail(&new->sibling, &root->child); + new->parent = root; + INIT_LIST_HEAD(&new->child); + return NULL; } static int __release_resource(struct resource *old, bool release_child) { - struct resource *tmp, **p, *chd; + struct resource *tmp, *next, *chd; - p = &old->parent->child; - for (;;) { - tmp = *p; - if (!tmp) - break; + list_for_each_entry_safe(tmp, next, &old->parent->child, sibling) { if (tmp == old) { - if (release_child || !(tmp->child)) { - *p = tmp->sibling; + if (release_child || list_empty(&tmp->child)) { + list_del(&tmp->sibling); } else { - for (chd = tmp->child;; chd = chd->sibling) { + list_for_each_entry(chd, &tmp->child, sibling) chd->parent = tmp->parent; - if (!(chd->sibling)) - break; - } - *p = tmp->child; - chd->sibling = tmp->sibling; + list_splice(&tmp->child, tmp->sibling.prev); + list_del(&tmp->sibling); } + old->parent = NULL; return 0; } - p = &tmp->sibling; } return -EINVAL; } static void __release_child_resources(struct resource *r) { - struct resource *tmp, *p; + struct resource *tmp, *next; resource_size_t size; - p = r->child; - r->child = NULL; - while (p) { - tmp = p; - p = p->sibling; - + list_for_each_entry_safe(tmp, next, &r->child, sibling) { tmp->parent = NULL; - tmp->sibling = NULL; + INIT_LIST_HEAD(&tmp->sibling); __release_child_resources(tmp); printk(KERN_DEBUG "release child resource %pR\n", tmp); @@ -292,6 +294,8 @@ static void __release_child_resources(struct resource *r) tmp->start = 0; tmp->end = size - 1; } + + INIT_LIST_HEAD(&tmp->child); } void release_child_resources(struct resource *r) @@ -376,7 +380,8 @@ static int find_next_iomem_res(struct resource *res, unsigned long desc, read_lock(&resource_lock); - for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) { + for (p = resource_first_child(&iomem_resource.child); p; + p = next_resource(p, sibling_only)) { if ((p->flags & res->flags) != res->flags) continue; if ((desc != IORES_DESC_NONE) && (desc != p->desc)) @@ -564,7 +569,7 @@ int region_intersects(resource_size_t start, size_t size, unsigned long flags, struct resource *p; read_lock(&resource_lock); - for (p = iomem_resource.child; p ; p = p->sibling) { + list_for_each_entry(p, &iomem_resource.child, sibling) { bool is_type = (((p->flags & flags) == flags) && ((desc == IORES_DESC_NONE) || (desc == p->desc))); @@ -618,7 +623,7 @@ static int __find_resource(struct resource *root, struct resource *old, resource_size_t size, struct resource_constraint *constraint) { - struct resource *this = root->child; + struct resource *this = resource_first_child(&root->child); struct resource tmp = *new, avail, alloc; tmp.start = root->start; @@ -628,7 +633,7 @@ static int __find_resource(struct resource *root, struct resource *old, */ if (this && this->start == root->start) { tmp.start = (this == old) ? old->start : this->end + 1; - this = this->sibling; + this = resource_sibling(this); } for(;;) { if (this) @@ -664,7 +669,7 @@ next: if (!this || this->end == root->end) if (this != old) tmp.start = this->end + 1; - this = this->sibling; + this = resource_sibling(this); } return -EBUSY; } @@ -708,7 +713,7 @@ static int reallocate_resource(struct resource *root, struct resource *old, goto out; } - if (old->child) { + if (!list_empty(&old->child)) { err = -EBUSY; goto out; } @@ -789,7 +794,7 @@ 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) { + list_for_each_entry(res, &root->child, sibling) { if (res->start == start) break; } @@ -822,32 +827,27 @@ static struct resource * __insert_resource(struct resource *parent, struct resou break; } - for (next = first; ; next = next->sibling) { + for (next = first; ; next = resource_sibling(next)) { /* Partial overlap? Bad, and unfixable */ if (next->start < new->start || next->end > new->end) return next; - if (!next->sibling) + if (!resource_sibling(next)) break; - if (next->sibling->start > new->end) + if (resource_sibling(next)->start > new->end) break; } - new->parent = parent; - new->sibling = next->sibling; - new->child = first; + list_add(&new->sibling, &next->sibling); + INIT_LIST_HEAD(&new->child); - next->sibling = NULL; - for (next = first; next; next = next->sibling) + /* + * From first to next, they all fall into new's region, so change them + * as new's children. + */ + list_cut_position(&new->child, first->sibling.prev, &next->sibling); + list_for_each_entry(next, &new->child, 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; } @@ -969,19 +969,17 @@ static int __adjust_resource(struct resource *res, resource_size_t start, if ((start < parent->start) || (end > parent->end)) goto out; - if (res->sibling && (res->sibling->start <= end)) + if (resource_sibling(res) && (resource_sibling(res)->start <= end)) goto out; - tmp = parent->child; - if (tmp != res) { - while (tmp->sibling != res) - tmp = tmp->sibling; + if (res->sibling.prev != &parent->child) { + tmp = list_prev_entry(res, sibling); if (start <= tmp->end) goto out; } skip: - for (tmp = res->child; tmp; tmp = tmp->sibling) + list_for_each_entry(tmp, &res->child, sibling) if ((tmp->start < start) || (tmp->end > end)) goto out; @@ -1206,34 +1204,32 @@ EXPORT_SYMBOL(__request_region); void __release_region(struct resource *parent, resource_size_t start, resource_size_t n) { - struct resource **p; + struct resource *res; resource_size_t end; - p = &parent->child; + res = resource_first_child(&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; + res = resource_first_child(&res->child); continue; } if (res->start != start || res->end != end) break; - *p = res->sibling; + list_del(&res->sibling); write_unlock(&resource_lock); if (res->flags & IORESOURCE_MUXED) wake_up(&muxed_resource_wait); free_resource(res); return; } - p = &res->sibling; + res = resource_sibling(res); } write_unlock(&resource_lock); @@ -1268,9 +1264,7 @@ EXPORT_SYMBOL(__release_region); int release_mem_region_adjustable(struct resource *parent, resource_size_t start, resource_size_t size) { - struct resource **p; - struct resource *res; - struct resource *new_res; + struct resource *res, *new_res; resource_size_t end; int ret = -EINVAL; @@ -1281,16 +1275,16 @@ int release_mem_region_adjustable(struct resource *parent, /* The alloc_resource() result gets checked later */ new_res = alloc_resource(GFP_KERNEL); - p = &parent->child; + res = resource_first_child(&parent->child); write_lock(&resource_lock); - while ((res = *p)) { + while ((res)) { 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; + res = resource_sibling(res); continue; } @@ -1298,14 +1292,14 @@ int release_mem_region_adjustable(struct resource *parent, break; if (!(res->flags & IORESOURCE_BUSY)) { - p = &res->child; + res = resource_first_child(&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; + list_del(&res->sibling); free_resource(res); ret = 0; } else if (res->start == start && res->end != end) { @@ -1328,14 +1322,13 @@ int release_mem_region_adjustable(struct resource *parent, new_res->flags = res->flags; new_res->desc = res->desc; new_res->parent = res->parent; - new_res->sibling = res->sibling; - new_res->child = NULL; + INIT_LIST_HEAD(&new_res->child); ret = __adjust_resource(res, res->start, start - res->start); if (ret) break; - res->sibling = new_res; + list_add(&new_res->sibling, &res->sibling); new_res = NULL; } @@ -1516,7 +1509,7 @@ static int __init reserve_setup(char *str) res->end = io_start + io_num - 1; res->flags |= IORESOURCE_BUSY; res->desc = IORES_DESC_NONE; - res->child = NULL; + INIT_LIST_HEAD(&res->child); if (request_resource(parent, res) == 0) reserved = x+1; } @@ -1536,7 +1529,7 @@ int iomem_map_sanity_check(resource_size_t addr, unsigned long size) loff_t l; read_lock(&resource_lock); - for (p = p->child; p ; p = r_next(NULL, p, &l)) { + for (p = resource_first_child(&p->child); p; p = r_next(NULL, p, &l)) { /* * We can probably skip the resources without * IORESOURCE_IO attribute? @@ -1592,7 +1585,7 @@ bool iomem_is_exclusive(u64 addr) addr = addr & PAGE_MASK; read_lock(&resource_lock); - for (p = p->child; p ; p = r_next(NULL, p, &l)) { + for (p = resource_first_child(&p->child); p; p = r_next(NULL, p, &l)) { /* * We can probably skip the resources without * IORESOURCE_IO attribute? -- 2.13.6 _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm