From: Bartosz Golaszewski <brgl@bgdev.pl> To: Jonathan Cameron <jic23@kernel.org>, Hartmut Knaack <knaack.h@gmx.de>, Lars-Peter Clausen <lars@metafoo.de>, Peter Meerwald-Stadler <pmeerw@pmeerw.net>, Michal Simek <michal.simek@xilinx.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Guenter Roeck <linux@roeck-us.net>, Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: linux-iio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski <bgolaszewski@baylibre.com> Subject: [PATCH v6 1/3] devres: provide devm_krealloc() Date: Sun, 2 Aug 2020 10:34:56 +0200 [thread overview] Message-ID: <20200802083458.24323-2-brgl@bgdev.pl> (raw) In-Reply-To: <20200802083458.24323-1-brgl@bgdev.pl> From: Bartosz Golaszewski <bgolaszewski@baylibre.com> Implement the managed variant of krealloc(). This function works with all memory allocated by devm_kmalloc() (or devres functions using it implicitly like devm_kmemdup(), devm_kstrdup() etc.). Managed realloc'ed chunks can be manually released with devm_kfree(). Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> --- .../driver-api/driver-model/devres.rst | 1 + drivers/base/devres.c | 65 +++++++++++++++++++ include/linux/device.h | 2 + 3 files changed, 68 insertions(+) diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst index eaaaafc21134..f318a5c0033c 100644 --- a/Documentation/driver-api/driver-model/devres.rst +++ b/Documentation/driver-api/driver-model/devres.rst @@ -354,6 +354,7 @@ MEM devm_kmalloc() devm_kmalloc_array() devm_kmemdup() + devm_krealloc() devm_kstrdup() devm_kvasprintf() devm_kzalloc() diff --git a/drivers/base/devres.c b/drivers/base/devres.c index ed615d3b9cf1..68a5a7201065 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -837,6 +837,71 @@ void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) } EXPORT_SYMBOL_GPL(devm_kmalloc); +/** + * devm_krealloc - Resource-managed krealloc() + * @dev: Device to re-allocate memory for + * @ptr: Pointer to the memory chunk to re-allocate + * @new_size: New allocation size + * @gfp: Allocation gfp flags + * + * Managed krealloc(). Resizes the memory chunk allocated with devm_kmalloc(). + * Behaves similarly to regular krealloc(): if @ptr is NULL or ZERO_SIZE_PTR, + * it's the equivalent of devm_kmalloc(). If new_size is zero, it frees the + * previously allocated memory and returns ZERO_SIZE_PTR. This function doesn't + * change the order in which the release callback for the re-alloc'ed devres + * will be called (except when falling back to devm_kmalloc() or when freeing + * resources when new_size is zero). The contents of the memory are preserved + * up to the lesser of new and old sizes. + */ +void *devm_krealloc(struct device *dev, void *ptr, size_t new_size, gfp_t gfp) +{ + struct devres *old_dr, *new_dr; + struct list_head old_head; + unsigned long flags; + size_t total_size; + + if (unlikely(!new_size)) { + devm_kfree(dev, ptr); + return ZERO_SIZE_PTR; + } + + if (unlikely(ZERO_OR_NULL_PTR(ptr))) + return devm_kmalloc(dev, new_size, gfp); + + if (WARN_ON(is_kernel_rodata((unsigned long)ptr))) + /* + * We cannot reliably realloc a const string returned by + * devm_kstrdup_const(). + */ + return NULL; + + if (!check_dr_size(new_size, &total_size)) + return NULL; + + spin_lock_irqsave(&dev->devres_lock, flags); + old_dr = find_dr(dev, devm_kmalloc_release, devm_kmalloc_match, ptr); + spin_unlock_irqrestore(&dev->devres_lock, flags); + if (!old_dr) { + WARN(1, "Memory chunk not managed or managed by a different device."); + return NULL; + } + + old_head = old_dr->node.entry; + + new_dr = krealloc(old_dr, total_size, gfp); + if (!new_dr) + return NULL; + + if (new_dr != old_dr) { + spin_lock_irqsave(&dev->devres_lock, flags); + list_replace(&old_head, &new_dr->node.entry); + spin_unlock_irqrestore(&dev->devres_lock, flags); + } + + return new_dr->data; +} +EXPORT_SYMBOL_GPL(devm_krealloc); + /** * devm_kstrdup - Allocate resource managed space and * copy an existing string into that. diff --git a/include/linux/device.h b/include/linux/device.h index 79ce404619e6..51fb33400d7a 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -206,6 +206,8 @@ int devres_release_group(struct device *dev, void *id); /* managed devm_k.alloc/kfree for device drivers */ void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc; +void *devm_krealloc(struct device *dev, void *ptr, size_t size, + gfp_t gfp) __must_check; __printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt, va_list ap) __malloc; __printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp, -- 2.26.1
WARNING: multiple messages have this Message-ID (diff)
From: Bartosz Golaszewski <brgl@bgdev.pl> To: Jonathan Cameron <jic23@kernel.org>, Hartmut Knaack <knaack.h@gmx.de>, Lars-Peter Clausen <lars@metafoo.de>, Peter Meerwald-Stadler <pmeerw@pmeerw.net>, Michal Simek <michal.simek@xilinx.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Guenter Roeck <linux@roeck-us.net>, Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: linux-iio@vger.kernel.org, Bartosz Golaszewski <bgolaszewski@baylibre.com>, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v6 1/3] devres: provide devm_krealloc() Date: Sun, 2 Aug 2020 10:34:56 +0200 [thread overview] Message-ID: <20200802083458.24323-2-brgl@bgdev.pl> (raw) In-Reply-To: <20200802083458.24323-1-brgl@bgdev.pl> From: Bartosz Golaszewski <bgolaszewski@baylibre.com> Implement the managed variant of krealloc(). This function works with all memory allocated by devm_kmalloc() (or devres functions using it implicitly like devm_kmemdup(), devm_kstrdup() etc.). Managed realloc'ed chunks can be manually released with devm_kfree(). Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> --- .../driver-api/driver-model/devres.rst | 1 + drivers/base/devres.c | 65 +++++++++++++++++++ include/linux/device.h | 2 + 3 files changed, 68 insertions(+) diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst index eaaaafc21134..f318a5c0033c 100644 --- a/Documentation/driver-api/driver-model/devres.rst +++ b/Documentation/driver-api/driver-model/devres.rst @@ -354,6 +354,7 @@ MEM devm_kmalloc() devm_kmalloc_array() devm_kmemdup() + devm_krealloc() devm_kstrdup() devm_kvasprintf() devm_kzalloc() diff --git a/drivers/base/devres.c b/drivers/base/devres.c index ed615d3b9cf1..68a5a7201065 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -837,6 +837,71 @@ void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) } EXPORT_SYMBOL_GPL(devm_kmalloc); +/** + * devm_krealloc - Resource-managed krealloc() + * @dev: Device to re-allocate memory for + * @ptr: Pointer to the memory chunk to re-allocate + * @new_size: New allocation size + * @gfp: Allocation gfp flags + * + * Managed krealloc(). Resizes the memory chunk allocated with devm_kmalloc(). + * Behaves similarly to regular krealloc(): if @ptr is NULL or ZERO_SIZE_PTR, + * it's the equivalent of devm_kmalloc(). If new_size is zero, it frees the + * previously allocated memory and returns ZERO_SIZE_PTR. This function doesn't + * change the order in which the release callback for the re-alloc'ed devres + * will be called (except when falling back to devm_kmalloc() or when freeing + * resources when new_size is zero). The contents of the memory are preserved + * up to the lesser of new and old sizes. + */ +void *devm_krealloc(struct device *dev, void *ptr, size_t new_size, gfp_t gfp) +{ + struct devres *old_dr, *new_dr; + struct list_head old_head; + unsigned long flags; + size_t total_size; + + if (unlikely(!new_size)) { + devm_kfree(dev, ptr); + return ZERO_SIZE_PTR; + } + + if (unlikely(ZERO_OR_NULL_PTR(ptr))) + return devm_kmalloc(dev, new_size, gfp); + + if (WARN_ON(is_kernel_rodata((unsigned long)ptr))) + /* + * We cannot reliably realloc a const string returned by + * devm_kstrdup_const(). + */ + return NULL; + + if (!check_dr_size(new_size, &total_size)) + return NULL; + + spin_lock_irqsave(&dev->devres_lock, flags); + old_dr = find_dr(dev, devm_kmalloc_release, devm_kmalloc_match, ptr); + spin_unlock_irqrestore(&dev->devres_lock, flags); + if (!old_dr) { + WARN(1, "Memory chunk not managed or managed by a different device."); + return NULL; + } + + old_head = old_dr->node.entry; + + new_dr = krealloc(old_dr, total_size, gfp); + if (!new_dr) + return NULL; + + if (new_dr != old_dr) { + spin_lock_irqsave(&dev->devres_lock, flags); + list_replace(&old_head, &new_dr->node.entry); + spin_unlock_irqrestore(&dev->devres_lock, flags); + } + + return new_dr->data; +} +EXPORT_SYMBOL_GPL(devm_krealloc); + /** * devm_kstrdup - Allocate resource managed space and * copy an existing string into that. diff --git a/include/linux/device.h b/include/linux/device.h index 79ce404619e6..51fb33400d7a 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -206,6 +206,8 @@ int devres_release_group(struct device *dev, void *id); /* managed devm_k.alloc/kfree for device drivers */ void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc; +void *devm_krealloc(struct device *dev, void *ptr, size_t size, + gfp_t gfp) __must_check; __printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt, va_list ap) __malloc; __printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp, -- 2.26.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-08-02 8:35 UTC|newest] Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-08-02 8:34 [PATCH v6 0/3] devres: provide and use devm_krealloc() Bartosz Golaszewski 2020-08-02 8:34 ` Bartosz Golaszewski 2020-08-02 8:34 ` Bartosz Golaszewski [this message] 2020-08-02 8:34 ` [PATCH v6 1/3] devres: provide devm_krealloc() Bartosz Golaszewski 2020-08-02 10:42 ` Andy Shevchenko 2020-08-02 10:42 ` Andy Shevchenko 2020-08-03 19:31 ` Bartosz Golaszewski 2020-08-03 19:31 ` Bartosz Golaszewski 2020-08-02 8:34 ` [PATCH v6 2/3] hwmon: pmbus: use more devres helpers Bartosz Golaszewski 2020-08-02 8:34 ` Bartosz Golaszewski 2020-08-02 8:34 ` [PATCH v6 3/3] iio: adc: xilinx-xadc: use devm_krealloc() Bartosz Golaszewski 2020-08-02 8:34 ` Bartosz Golaszewski
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