From 469e1906a1b121ecb0c2ef43f28a98fd9d453831 Mon Sep 17 00:00:00 2001 From: Tomas Winkler Date: Sat, 8 Feb 2020 20:44:07 +0200 Subject: platform: constify properties in platform_device Constify 'struct property_entry *properties' in platform_device. It is always passed around as a pointer const struct. Reviewed-by: Andy Shevchenko Signed-off-by: Tomas Winkler Link: https://lore.kernel.org/r/20200208184407.1294-2-tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman --- include/linux/platform_device.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/platform_device.h') diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 276a03c24691..8e83c6ff140d 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -89,7 +89,7 @@ struct platform_device_info { size_t size_data; u64 dma_mask; - struct property_entry *properties; + const struct property_entry *properties; }; extern struct platform_device *platform_device_register_full( const struct platform_device_info *pdevinfo); -- cgit v1.2.3 From e3a36eb6dfaeea8175c05d5915dcf0b939be6dab Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 11 Mar 2020 17:07:10 +0100 Subject: driver code: clarify and fix platform device DMA mask allocation This does three inter-related things to clarify the usage of the platform device dma_mask field. In the process, fix the bug introduced by cdfee5623290 ("driver core: initialize a default DMA mask for platform device") that caused Artem Tashkinov's laptop to not boot with newer Fedora kernels. This does: - First off, rename the field to "platform_dma_mask" to make it greppable. We have way too many different random fields called "dma_mask" in various data structures, where some of them are actual masks, and some of them are just pointers to the mask. And the structures all have pointers to each other, or embed each other inside themselves, and "pdev" sometimes means "platform device" and sometimes it means "PCI device". So to make it clear in the code when you actually use this new field, give it a unique name (it really should be something even more unique like "platform_device_dma_mask", since it's per platform device, not per platform, but that gets old really fast, and this is unique enough in context). To further clarify when the field gets used, initialize it when we actually start using it with the default value. - Then, use this field instead of the random one-off allocation in platform_device_register_full() that is now unnecessary since we now already have a perfectly fine allocation for it in the platform device structure. - The above then allows us to fix the actual bug, where the error path of platform_device_register_full() would unconditionally free the platform device DMA allocation with 'kfree()'. That kfree() was dont regardless of whether the allocation had been done earlier with the (now removed) kmalloc, or whether setup_pdev_dma_masks() had already been used and the dma_mask pointer pointed to the mask that was part of the platform device. It seems most people never triggered the error path, or only triggered it from a call chain that set an explicit pdevinfo->dma_mask value (and thus caused the unnecessary allocation that was "cleaned up" in the error path) before calling platform_device_register_full(). Robin Murphy points out that in Artem's case the wdat_wdt driver failed in platform_device_add(), and that was the one that had called platform_device_register_full() with pdevinfo.dma_mask = 0, and would have caused that kfree() of pdev.dma_mask corrupting the heap. A later unrelated kmalloc() then oopsed due to the heap corruption. Fixes: cdfee5623290 ("driver core: initialize a default DMA mask for platform device") Reported-bisected-and-tested-by: Artem S. Tashkinov Reviewed-by: Robin Murphy Cc: Greg Kroah-Hartman Signed-off-by: Christoph Hellwig Signed-off-by: Linus Torvalds --- drivers/base/platform.c | 25 ++++++------------------- include/linux/platform_device.h | 2 +- 2 files changed, 7 insertions(+), 20 deletions(-) (limited to 'include/linux/platform_device.h') diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 7fa654f1288b..b5ce7b085795 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -363,10 +363,10 @@ static void setup_pdev_dma_masks(struct platform_device *pdev) { if (!pdev->dev.coherent_dma_mask) pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32); - if (!pdev->dma_mask) - pdev->dma_mask = DMA_BIT_MASK(32); - if (!pdev->dev.dma_mask) - pdev->dev.dma_mask = &pdev->dma_mask; + if (!pdev->dev.dma_mask) { + pdev->platform_dma_mask = DMA_BIT_MASK(32); + pdev->dev.dma_mask = &pdev->platform_dma_mask; + } }; /** @@ -662,20 +662,8 @@ struct platform_device *platform_device_register_full( pdev->dev.of_node_reused = pdevinfo->of_node_reused; if (pdevinfo->dma_mask) { - /* - * This memory isn't freed when the device is put, - * I don't have a nice idea for that though. Conceptually - * dma_mask in struct device should not be a pointer. - * See http://thread.gmane.org/gmane.linux.kernel.pci/9081 - */ - pdev->dev.dma_mask = - kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL); - if (!pdev->dev.dma_mask) - goto err; - - kmemleak_ignore(pdev->dev.dma_mask); - - *pdev->dev.dma_mask = pdevinfo->dma_mask; + pdev->platform_dma_mask = pdevinfo->dma_mask; + pdev->dev.dma_mask = &pdev->platform_dma_mask; pdev->dev.coherent_dma_mask = pdevinfo->dma_mask; } @@ -700,7 +688,6 @@ struct platform_device *platform_device_register_full( if (ret) { err: ACPI_COMPANION_SET(&pdev->dev, NULL); - kfree(pdev->dev.dma_mask); platform_device_put(pdev); return ERR_PTR(ret); } diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 276a03c24691..041bfa412aa0 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -24,7 +24,7 @@ struct platform_device { int id; bool id_auto; struct device dev; - u64 dma_mask; + u64 platform_dma_mask; u32 num_resources; struct resource *resource; -- cgit v1.2.3 From 890cc39a879906b63912482dfc41944579df2dc6 Mon Sep 17 00:00:00 2001 From: Dejin Zheng Date: Tue, 24 Mar 2020 00:06:08 +0800 Subject: drivers: provide devm_platform_get_and_ioremap_resource() Since commit "drivers: provide devm_platform_ioremap_resource()", it was wrap platform_get_resource() and devm_ioremap_resource() as single helper devm_platform_ioremap_resource(). but now, many drivers still used platform_get_resource() and devm_ioremap_resource() together in the kernel tree. The reason can not be replaced is they still need use the resource variables obtained by platform_get_resource(). so provide this helper. Suggested-by: Geert Uytterhoeven Suggested-by: Sergei Shtylyov Reviewed-by: Geert Uytterhoeven Signed-off-by: Dejin Zheng Link: https://lore.kernel.org/r/20200323160612.17277-2-zhengdejin5@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/platform.c | 22 ++++++++++++++++++++++ include/linux/platform_device.h | 3 +++ 2 files changed, 25 insertions(+) (limited to 'include/linux/platform_device.h') diff --git a/drivers/base/platform.c b/drivers/base/platform.c index b5ce7b085795..8f0f62bdc58e 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -62,6 +62,28 @@ struct resource *platform_get_resource(struct platform_device *dev, EXPORT_SYMBOL_GPL(platform_get_resource); #ifdef CONFIG_HAS_IOMEM +/** + * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a + * platform device and get resource + * + * @pdev: platform device to use both for memory resource lookup as well as + * resource management + * @index: resource index + * @res: optional output parameter to store a pointer to the obtained resource. + */ +void __iomem * +devm_platform_get_and_ioremap_resource(struct platform_device *pdev, + unsigned int index, struct resource **res) +{ + struct resource *r; + + r = platform_get_resource(pdev, IORESOURCE_MEM, index); + if (res) + *res = r; + return devm_ioremap_resource(&pdev->dev, r); +} +EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource); + /** * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform * device diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 041bfa412aa0..f242f66db19d 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -55,6 +55,9 @@ extern struct device * platform_find_device_by_driver(struct device *start, const struct device_driver *drv); extern void __iomem * +devm_platform_get_and_ioremap_resource(struct platform_device *pdev, + unsigned int index, struct resource **res); +extern void __iomem * devm_platform_ioremap_resource(struct platform_device *pdev, unsigned int index); extern void __iomem * -- cgit v1.2.3