devres: device resource management

Implement device resource management, in short, devres.  A device
driver can allocate arbirary size of devres data which is associated
with a release function.  On driver detach, release function is
invoked on the devres data, then, devres data is freed.

devreses are typed by associated release functions.  Some devreses are
better represented by single instance of the type while others need
multiple instances sharing the same release function.  Both usages are
supported.

devreses can be grouped using devres group such that a device driver
can easily release acquired resources halfway through initialization
or selectively release resources (e.g. resources for port 1 out of 4
ports).

This patch adds devres core including documentation and the following
managed interfaces.

* alloc/free	: devm_kzalloc(), devm_kzfree()
* IO region	: devm_request_region(), devm_release_region()
* IRQ		: devm_request_irq(), devm_free_irq()
* DMA		: dmam_alloc_coherent(), dmam_free_coherent(),
		  dmam_declare_coherent_memory(), dmam_pool_create(),
		  dmam_pool_destroy()
* PCI		: pcim_enable_device(), pcim_pin_device(), pci_is_managed()
* iomap		: devm_ioport_map(), devm_ioport_unmap(), devm_ioremap(),
		  devm_ioremap_nocache(), devm_iounmap(), pcim_iomap_table(),
		  pcim_iomap(), pcim_iounmap()

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

7 files changed, 125 insertions, 1 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index 5ca1cdb..26e4692 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -354,6 +354,41 @@ extern int __must_check device_create_bin_file(struct device *dev,
 					       struct bin_attribute *attr);
 extern void device_remove_bin_file(struct device *dev,
 				   struct bin_attribute *attr);
+
+/* device resource management */
+typedef void (*dr_release_t)(struct device *dev, void *res);
+typedef int (*dr_match_t)(struct device *dev, void *res, void *match_data);
+
+#ifdef CONFIG_DEBUG_DEVRES
+extern void * __devres_alloc(dr_release_t release, size_t size, gfp_t gfp,
+			     const char *name);
+#define devres_alloc(release, size, gfp) \
+	__devres_alloc(release, size, gfp, #release)
+#else
+extern void * devres_alloc(dr_release_t release, size_t size, gfp_t gfp);
+#endif
+extern void devres_free(void *res);
+extern void devres_add(struct device *dev, void *res);
+extern void * devres_find(struct device *dev, dr_release_t release,
+			  dr_match_t match, void *match_data);
+extern void * devres_get(struct device *dev, void *new_res,
+			 dr_match_t match, void *match_data);
+extern void * devres_remove(struct device *dev, dr_release_t release,
+			    dr_match_t match, void *match_data);
+extern int devres_destroy(struct device *dev, dr_release_t release,
+			  dr_match_t match, void *match_data);
+
+/* devres group */
+extern void * __must_check devres_open_group(struct device *dev, void *id,
+					     gfp_t gfp);
+extern void devres_close_group(struct device *dev, void *id);
+extern void devres_remove_group(struct device *dev, void *id);
+extern int devres_release_group(struct device *dev, void *id);
+
+/* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
+extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
+extern void devm_kfree(struct device *dev, void *p);
+
 struct device {
 	struct klist		klist_children;
 	struct klist_node	knode_parent;		/* node in sibling list */
@@ -397,6 +432,9 @@ struct device {
 	/* arch specific additions */
 	struct dev_archdata	archdata;
 
+	spinlock_t		devres_lock;
+	struct list_head	devres_head;
+
 	/* class_device migration path */
 	struct list_head	node;
 	struct class		*class;
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index ff203c4..9a663c6 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -66,6 +66,33 @@ dma_mark_declared_memory_occupied(struct device *dev,
 }
 #endif
 
-#endif
+/*
+ * Managed DMA API
+ */
+extern void *dmam_alloc_coherent(struct device *dev, size_t size,
+				 dma_addr_t *dma_handle, gfp_t gfp);
+extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
+			       dma_addr_t dma_handle);
+extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
+				    dma_addr_t *dma_handle, gfp_t gfp);
+extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
+				  dma_addr_t dma_handle);
+#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
+extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+					dma_addr_t device_addr, size_t size,
+					int flags);
+extern void dmam_release_declared_memory(struct device *dev);
+#else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
+static inline int dmam_declare_coherent_memory(struct device *dev,
+				dma_addr_t bus_addr, dma_addr_t device_addr,
+				size_t size, gfp_t gfp)
+{
+	return 0;
+}
 
+static inline void dmam_release_declared_memory(struct device *dev)
+{
+}
+#endif /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
 
+#endif
diff --git a/include/linux/dmapool.h b/include/linux/dmapool.h
index 76f12f4..022e34f 100644
--- a/include/linux/dmapool.h
+++ b/include/linux/dmapool.h
@@ -24,5 +24,12 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
 
 void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t addr);
 
+/*
+ * Managed DMA pool
+ */
+struct dma_pool *dmam_pool_create(const char *name, struct device *dev,
+				  size_t size, size_t align, size_t allocation);
+void dmam_pool_destroy(struct dma_pool *pool);
+
 #endif
 
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index e36e86c..5a8ba0b 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -12,6 +12,7 @@
 #include <linux/sched.h>
 #include <linux/irqflags.h>
 #include <linux/bottom_half.h>
+#include <linux/device.h>
 #include <asm/atomic.h>
 #include <asm/ptrace.h>
 #include <asm/system.h>
@@ -83,6 +84,11 @@ extern int request_irq(unsigned int, irq_handler_t handler,
 		       unsigned long, const char *, void *);
 extern void free_irq(unsigned int, void *);
 
+extern int devm_request_irq(struct device *dev, unsigned int irq,
+			    irq_handler_t handler, unsigned long irqflags,
+			    const char *devname, void *dev_id);
+extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
+
 /*
  * On lockdep we dont want to enable hardirqs in hardirq
  * context. Use local_irq_enable_in_hardirq() to annotate
diff --git a/include/linux/io.h b/include/linux/io.h
index 81877ea..f5edf9c 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -28,6 +28,23 @@ void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
 int ioremap_page_range(unsigned long addr, unsigned long end,
 		       unsigned long phys_addr, pgprot_t prot);
 
+/*
+ * Managed iomap interface
+ */
+void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
+			       unsigned int nr);
+void devm_ioport_unmap(struct device *dev, void __iomem *addr);
+
+void __iomem * devm_ioremap(struct device *dev, unsigned long offset,
+			    unsigned long size);
+void __iomem * devm_ioremap_nocache(struct device *dev, unsigned long offset,
+				    unsigned long size);
+void devm_iounmap(struct device *dev, void __iomem *addr);
+
+void __iomem * pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
+void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr);
+void __iomem * const * pcim_iomap_table(struct pci_dev *pdev);
+
 /**
  *	check_signature		-	find BIOS signatures
  *	@io_addr: mmio address to check
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 15228d7..6859a3b 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -137,4 +137,24 @@ static inline int __deprecated check_region(resource_size_t s,
 {
 	return __check_region(&ioport_resource, s, n);
 }
+
+/* Wrappers for managed devices */
+struct device;
+#define devm_request_region(dev,start,n,name) \
+	__devm_request_region(dev, &ioport_resource, (start), (n), (name))
+#define devm_request_mem_region(dev,start,n,name) \
+	__devm_request_region(dev, &iomem_resource, (start), (n), (name))
+
+extern struct resource * __devm_request_region(struct device *dev,
+				struct resource *parent, resource_size_t start,
+				resource_size_t n, const char *name);
+
+#define devm_release_region(start,n) \
+	__devm_release_region(dev, &ioport_resource, (start), (n))
+#define devm_release_mem_region(start,n) \
+	__devm_release_region(dev, &iomem_resource, (start), (n))
+
+extern void __devm_release_region(struct device *dev, struct resource *parent,
+				  resource_size_t start, resource_size_t n);
+
 #endif	/* _LINUX_IOPORT_H */
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 805412c..9e3042e 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -167,6 +167,7 @@ struct pci_dev {
 	unsigned int	broken_parity_status:1;	/* Device generates false positive parity */
 	unsigned int 	msi_enabled:1;
 	unsigned int	msix_enabled:1;
+	unsigned int	is_managed:1;
 	atomic_t	enable_cnt;	/* pci_enable_device has been called */
 
 	u32		saved_config_space[16]; /* config space saved at suspend time */
@@ -528,6 +529,14 @@ static inline int pci_write_config_dword(struct pci_dev *dev, int where, u32 val
 
 int __must_check pci_enable_device(struct pci_dev *dev);
 int __must_check pci_enable_device_bars(struct pci_dev *dev, int mask);
+int __must_check pcim_enable_device(struct pci_dev *pdev);
+void pcim_pin_device(struct pci_dev *pdev);
+
+static inline int pci_is_managed(struct pci_dev *pdev)
+{
+	return pdev->is_managed;
+}
+
 void pci_disable_device(struct pci_dev *dev);
 void pci_set_master(struct pci_dev *dev);
 #define HAVE_PCI_SET_MWI