From 4dd2b32f3c48112da2ffe55279aedc10c3784f90 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 4 Apr 2011 21:41:20 -0700 Subject: [PATCH] staging: memrar: remove driver from tree It's no longer needed at all. Cc: Ossama Othman Cc: Eugene Epshteyn Cc: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/staging/Kconfig | 2 - drivers/staging/Makefile | 1 - drivers/staging/memrar/Kconfig | 15 - drivers/staging/memrar/Makefile | 2 - drivers/staging/memrar/TODO | 43 - drivers/staging/memrar/memrar-abi | 89 -- drivers/staging/memrar/memrar.h | 174 ---- drivers/staging/memrar/memrar_allocator.c | 432 --------- drivers/staging/memrar/memrar_allocator.h | 149 --- drivers/staging/memrar/memrar_handler.c | 1007 --------------------- 10 files changed, 1914 deletions(-) delete mode 100644 drivers/staging/memrar/Kconfig delete mode 100644 drivers/staging/memrar/Makefile delete mode 100644 drivers/staging/memrar/TODO delete mode 100644 drivers/staging/memrar/memrar-abi delete mode 100644 drivers/staging/memrar/memrar.h delete mode 100644 drivers/staging/memrar/memrar_allocator.c delete mode 100644 drivers/staging/memrar/memrar_allocator.h delete mode 100644 drivers/staging/memrar/memrar_handler.c diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig index 18b43fcb417..dca4a0bb6ca 100644 --- a/drivers/staging/Kconfig +++ b/drivers/staging/Kconfig @@ -117,8 +117,6 @@ source "drivers/staging/hv/Kconfig" source "drivers/staging/vme/Kconfig" -source "drivers/staging/memrar/Kconfig" - source "drivers/staging/sep/Kconfig" source "drivers/staging/iio/Kconfig" diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile index cfd13cd55ef..eb93012b6f5 100644 --- a/drivers/staging/Makefile +++ b/drivers/staging/Makefile @@ -40,7 +40,6 @@ obj-$(CONFIG_VT6655) += vt6655/ obj-$(CONFIG_VT6656) += vt6656/ obj-$(CONFIG_HYPERV) += hv/ obj-$(CONFIG_VME_BUS) += vme/ -obj-$(CONFIG_MRST_RAR_HANDLER) += memrar/ obj-$(CONFIG_DX_SEP) += sep/ obj-$(CONFIG_IIO) += iio/ obj-$(CONFIG_CS5535_GPIO) += cs5535_gpio/ diff --git a/drivers/staging/memrar/Kconfig b/drivers/staging/memrar/Kconfig deleted file mode 100644 index cbeebc55090..00000000000 --- a/drivers/staging/memrar/Kconfig +++ /dev/null @@ -1,15 +0,0 @@ -config MRST_RAR_HANDLER - tristate "RAR handler driver for Intel Moorestown platform" - depends on RAR_REGISTER - ---help--- - This driver provides a memory management interface to - restricted access regions (RAR) available on the Intel - Moorestown platform. - - Once locked down, restricted access regions are only - accessible by specific hardware on the platform. The x86 - CPU is typically not one of those platforms. As such this - driver does not access RAR, and only provides a buffer - allocation/bookkeeping mechanism. - - If unsure, say N. diff --git a/drivers/staging/memrar/Makefile b/drivers/staging/memrar/Makefile deleted file mode 100644 index a3336c00cc5..00000000000 --- a/drivers/staging/memrar/Makefile +++ /dev/null @@ -1,2 +0,0 @@ -obj-$(CONFIG_MRST_RAR_HANDLER) += memrar.o -memrar-y := memrar_allocator.o memrar_handler.o diff --git a/drivers/staging/memrar/TODO b/drivers/staging/memrar/TODO deleted file mode 100644 index 435e09ba44c..00000000000 --- a/drivers/staging/memrar/TODO +++ /dev/null @@ -1,43 +0,0 @@ -RAR Handler (memrar) Driver TODO Items -====================================== - -Maintainer: Eugene Epshteyn - -memrar.h --------- -1. This header exposes the driver's user space and kernel space - interfaces. It should be moved to , or - something along those lines, when this memrar driver is moved out - of `staging'. - a. It would be ideal if staging/rar_register/rar_register.h was - moved to the same directory. - -memrar_allocator.[ch] ---------------------- -1. Address potential fragmentation issues with the memrar_allocator. - -2. Hide struct memrar_allocator details/fields. They need not be - exposed to the user. - a. Forward declare struct memrar_allocator. - b. Move all three struct definitions to `memrar_allocator.c' - source file. - c. Add a memrar_allocator_largest_free_area() function, or - something like that to get access to the value of the struct - memrar_allocator "largest_free_area" field. This allows the - struct memrar_allocator fields to be completely hidden from - the user. The memrar_handler code really only needs this for - statistic gathering on-demand. - d. Do the same for the "capacity" field as the - "largest_free_area" field. - -3. Move memrar_allocator.* to kernel `lib' directory since it is HW - neutral. - a. Alternatively, use lib/genalloc.c instead. - b. A kernel port of Doug Lea's malloc() implementation may also - be an option. - -memrar_handler.c ----------------- -1. Split user space interface (ioctl code) from core/kernel code, - e.g.: - memrar_handler.c -> memrar_core.c, memrar_user.c diff --git a/drivers/staging/memrar/memrar-abi b/drivers/staging/memrar/memrar-abi deleted file mode 100644 index c23fc996a43..00000000000 --- a/drivers/staging/memrar/memrar-abi +++ /dev/null @@ -1,89 +0,0 @@ -What: /dev/memrar -Date: March 2010 -KernelVersion: 2.6.34 -Contact: Eugene Epshteyn -Description: The Intel Moorestown Restricted Access Region (RAR) - Handler driver exposes an ioctl() based interface that - allows a user to reserve and release blocks of RAR - memory. - - Note: A sysfs based one was not appropriate for the - RAR handler's usage model. - - ========================================================= - ioctl() Requests - ========================================================= - RAR_HANDLER_RESERVE - ------------------- - Description: Reserve RAR block. - Type: struct RAR_block_info - Direction: in/out - Errors: EINVAL (invalid RAR type or size) - ENOMEM (not enough RAR memory) - - RAR_HANDLER_STAT - ---------------- - Description: Get RAR statistics. - Type: struct RAR_stat - Direction: in/out - Errors: EINVAL (invalid RAR type) - - RAR_HANDLER_RELEASE - ------------------- - Description: Release previously reserved RAR block. - Type: 32 bit unsigned integer - (e.g. uint32_t), i.e the RAR "handle". - Direction: in - Errors: EINVAL (invalid RAR handle) - - - ========================================================= - ioctl() Request Parameter Types - ========================================================= - The structures referred to above are defined as - follows: - - /** - * struct RAR_block_info - user space struct that - * describes RAR buffer - * @type: Type of RAR memory (e.g., - * RAR_TYPE_VIDEO or RAR_TYPE_AUDIO) [in] - * @size: Requested size of a block in bytes to - * be reserved in RAR. [in] - * @handle: Handle that can be used to refer to - * reserved block. [out] - * - * This is the basic structure exposed to the user - * space that describes a given RAR buffer. It used - * as the parameter for the RAR_HANDLER_RESERVE ioctl. - * The buffer's underlying bus address is not exposed - * to the user. User space code refers to the buffer - * entirely by "handle". - */ - struct RAR_block_info { - __u32 type; - __u32 size; - __u32 handle; - }; - - /** - * struct RAR_stat - RAR statistics structure - * @type: Type of RAR memory (e.g., - * RAR_TYPE_VIDEO or - * RAR_TYPE_AUDIO) [in] - * @capacity: Total size of RAR memory - * region. [out] - * @largest_block_size: Size of the largest reservable - * block. [out] - * - * This structure is used for RAR_HANDLER_STAT ioctl. - */ - struct RAR_stat { - __u32 type; - __u32 capacity; - __u32 largest_block_size; - }; - - Lastly, the RAR_HANDLER_RELEASE ioctl expects a - "handle" to the RAR block of memory. It is a 32 bit - unsigned integer. diff --git a/drivers/staging/memrar/memrar.h b/drivers/staging/memrar/memrar.h deleted file mode 100644 index 0feb73b94c9..00000000000 --- a/drivers/staging/memrar/memrar.h +++ /dev/null @@ -1,174 +0,0 @@ -/* - * RAR Handler (/dev/memrar) internal driver API. - * Copyright (C) 2010 Intel Corporation. All rights reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General - * Public License as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be - * useful, but WITHOUT ANY WARRANTY; without even the implied - * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR - * PURPOSE. See the GNU General Public License for more details. - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the Free - * Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 02111-1307, USA. - * The full GNU General Public License is included in this - * distribution in the file called COPYING. - */ - - -#ifndef _MEMRAR_H -#define _MEMRAR_H - -#include -#include - - -/** - * struct RAR_stat - RAR statistics structure - * @type: Type of RAR memory (e.g., audio vs. video) - * @capacity: Total size of RAR memory region. - * @largest_block_size: Size of the largest reservable block. - * - * This structure is used for RAR_HANDLER_STAT ioctl and for the - * RAR_get_stat() user space wrapper function. - */ -struct RAR_stat { - __u32 type; - __u32 capacity; - __u32 largest_block_size; -}; - - -/** - * struct RAR_block_info - user space struct that describes RAR buffer - * @type: Type of RAR memory (e.g., audio vs. video) - * @size: Requested size of a block to be reserved in RAR. - * @handle: Handle that can be used to refer to reserved block. - * - * This is the basic structure exposed to the user space that - * describes a given RAR buffer. The buffer's underlying bus address - * is not exposed to the user. User space code refers to the buffer - * entirely by "handle". - */ -struct RAR_block_info { - __u32 type; - __u32 size; - __u32 handle; -}; - - -#define RAR_IOCTL_BASE 0xE0 - -/* Reserve RAR block. */ -#define RAR_HANDLER_RESERVE _IOWR(RAR_IOCTL_BASE, 0x00, struct RAR_block_info) - -/* Release previously reserved RAR block. */ -#define RAR_HANDLER_RELEASE _IOW(RAR_IOCTL_BASE, 0x01, __u32) - -/* Get RAR stats. */ -#define RAR_HANDLER_STAT _IOWR(RAR_IOCTL_BASE, 0x02, struct RAR_stat) - - -#ifdef __KERNEL__ - -/* -------------------------------------------------------------- */ -/* Kernel Side RAR Handler Interface */ -/* -------------------------------------------------------------- */ - -/** - * struct RAR_buffer - kernel space struct that describes RAR buffer - * @info: structure containing base RAR buffer information - * @bus_address: buffer bus address - * - * Structure that contains all information related to a given block of - * memory in RAR. It is generally only used when retrieving RAR - * related bus addresses. - * - * Note: This structure is used only by RAR-enabled drivers, and is - * not intended to be exposed to the user space. - */ -struct RAR_buffer { - struct RAR_block_info info; - dma_addr_t bus_address; -}; - -#if defined(CONFIG_MRST_RAR_HANDLER) -/** - * rar_reserve() - reserve RAR buffers - * @buffers: array of RAR_buffers where type and size of buffers to - * reserve are passed in, handle and bus address are - * passed out - * @count: number of RAR_buffers in the "buffers" array - * - * This function will reserve buffers in the restricted access regions - * of given types. - * - * It returns the number of successfully reserved buffers. Successful - * buffer reservations will have the corresponding bus_address field - * set to a non-zero value in the given buffers vector. - */ -extern size_t rar_reserve(struct RAR_buffer *buffers, - size_t count); - -/** - * rar_release() - release RAR buffers - * @buffers: array of RAR_buffers where handles to buffers to be - * released are passed in - * @count: number of RAR_buffers in the "buffers" array - * - * This function will release RAR buffers that were retrieved through - * a call to rar_reserve() or rar_handle_to_bus() by decrementing the - * reference count. The RAR buffer will be reclaimed when the - * reference count drops to zero. - * - * It returns the number of successfully released buffers. Successful - * releases will have their handle field set to zero in the given - * buffers vector. - */ -extern size_t rar_release(struct RAR_buffer *buffers, - size_t count); - -/** - * rar_handle_to_bus() - convert a vector of RAR handles to bus addresses - * @buffers: array of RAR_buffers containing handles to be - * converted to bus_addresses - * @count: number of RAR_buffers in the "buffers" array - - * This function will retrieve the RAR buffer bus addresses, type and - * size corresponding to the RAR handles provided in the buffers - * vector. - * - * It returns the number of successfully converted buffers. The bus - * address will be set to 0 for unrecognized handles. - * - * The reference count for each corresponding buffer in RAR will be - * incremented. Call rar_release() when done with the buffers. - */ -extern size_t rar_handle_to_bus(struct RAR_buffer *buffers, - size_t count); - -#else - -extern inline size_t rar_reserve(struct RAR_buffer *buffers, size_t count) -{ - return 0; -} - -extern inline size_t rar_release(struct RAR_buffer *buffers, size_t count) -{ - return 0; -} - -extern inline size_t rar_handle_to_bus(struct RAR_buffer *buffers, - size_t count) -{ - return 0; -} - -#endif /* MRST_RAR_HANDLER */ -#endif /* __KERNEL__ */ - -#endif /* _MEMRAR_H */ diff --git a/drivers/staging/memrar/memrar_allocator.c b/drivers/staging/memrar/memrar_allocator.c deleted file mode 100644 index a4f8c5846a0..00000000000 --- a/drivers/staging/memrar/memrar_allocator.c +++ /dev/null @@ -1,432 +0,0 @@ -/* - * memrar_allocator 1.0: An allocator for Intel RAR. - * - * Copyright (C) 2010 Intel Corporation. All rights reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General - * Public License as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be - * useful, but WITHOUT ANY WARRANTY; without even the implied - * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR - * PURPOSE. See the GNU General Public License for more details. - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the Free - * Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 02111-1307, USA. - * The full GNU General Public License is included in this - * distribution in the file called COPYING. - * - * - * ------------------------------------------------------------------ - * - * This simple allocator implementation provides a - * malloc()/free()-like interface for reserving space within a - * previously reserved block of memory. It is not specific to - * any hardware, nor is it coupled with the lower level paging - * mechanism. - * - * The primary goal of this implementation is to provide a means - * to partition an arbitrary block of memory without actually - * accessing the memory or incurring any hardware side-effects - * (e.g. paging). It is, in effect, a bookkeeping mechanism for - * buffers. - */ - - -#include "memrar_allocator.h" -#include -#include -#include - - -struct memrar_allocator *memrar_create_allocator(unsigned long base, - size_t capacity, - size_t block_size) -{ - struct memrar_allocator *allocator = NULL; - struct memrar_address_ranges *first_node = NULL; - - /* - * Make sure the base address is aligned on a block_size - * boundary. - * - * @todo Is this necessary? - */ - /* base = ALIGN(base, block_size); */ - - /* Validate parameters. - * - * Make sure we can allocate the entire memory space. Zero - * capacity or block size are obviously invalid. - */ - if (base == 0 - || capacity == 0 - || block_size == 0 - || ULONG_MAX - capacity < base - || capacity < block_size) - return allocator; - - /* - * There isn't much point in creating a memory allocator that - * is only capable of holding one block but we'll allow it, - * and issue a diagnostic. - */ - WARN(capacity < block_size * 2, - "memrar: Only one block available to allocator.\n"); - - allocator = kmalloc(sizeof(*allocator), GFP_KERNEL); - - if (allocator == NULL) - return allocator; - - mutex_init(&allocator->lock); - allocator->base = base; - - /* Round the capacity down to a multiple of block_size. */ - allocator->capacity = (capacity / block_size) * block_size; - - allocator->block_size = block_size; - - allocator->largest_free_area = allocator->capacity; - - /* Initialize the handle and free lists. */ - INIT_LIST_HEAD(&allocator->allocated_list.list); - INIT_LIST_HEAD(&allocator->free_list.list); - - first_node = kmalloc(sizeof(*first_node), GFP_KERNEL); - if (first_node == NULL) { - kfree(allocator); - allocator = NULL; - } else { - /* Full range of blocks is available. */ - first_node->range.begin = base; - first_node->range.end = base + allocator->capacity; - list_add(&first_node->list, - &allocator->free_list.list); - } - - return allocator; -} - -void memrar_destroy_allocator(struct memrar_allocator *allocator) -{ - /* - * Assume that the memory allocator lock isn't held at this - * point in time. Caller must ensure that. - */ - - struct memrar_address_ranges *pos = NULL; - struct memrar_address_ranges *n = NULL; - - if (allocator == NULL) - return; - - mutex_lock(&allocator->lock); - - /* Reclaim free list resources. */ - list_for_each_entry_safe(pos, - n, - &allocator->free_list.list, - list) { - list_del(&pos->list); - kfree(pos); - } - - mutex_unlock(&allocator->lock); - - kfree(allocator); -} - -unsigned long memrar_allocator_alloc(struct memrar_allocator *allocator, - size_t size) -{ - struct memrar_address_ranges *pos = NULL; - - size_t num_blocks; - unsigned long reserved_bytes; - - /* - * Address of allocated buffer. We assume that zero is not a - * valid address. - */ - unsigned long addr = 0; - - if (allocator == NULL || size == 0) - return addr; - - /* Reserve enough blocks to hold the amount of bytes requested. */ - num_blocks = DIV_ROUND_UP(size, allocator->block_size); - - reserved_bytes = num_blocks * allocator->block_size; - - mutex_lock(&allocator->lock); - - if (reserved_bytes > allocator->largest_free_area) { - mutex_unlock(&allocator->lock); - return addr; - } - - /* - * Iterate through the free list to find a suitably sized - * range of free contiguous memory blocks. - * - * We also take the opportunity to reset the size of the - * largest free area size statistic. - */ - list_for_each_entry(pos, &allocator->free_list.list, list) { - struct memrar_address_range * const fr = &pos->range; - size_t const curr_size = fr->end - fr->begin; - - if (curr_size >= reserved_bytes && addr == 0) { - struct memrar_address_range *range = NULL; - struct memrar_address_ranges * const new_node = - kmalloc(sizeof(*new_node), GFP_KERNEL); - - if (new_node == NULL) - break; - - list_add(&new_node->list, - &allocator->allocated_list.list); - - /* - * Carve out area of memory from end of free - * range. - */ - range = &new_node->range; - range->end = fr->end; - fr->end -= reserved_bytes; - range->begin = fr->end; - addr = range->begin; - - /* - * Check if largest area has decreased in - * size. We'll need to continue scanning for - * the next largest area if it has. - */ - if (curr_size == allocator->largest_free_area) - allocator->largest_free_area -= - reserved_bytes; - else - break; - } - - /* - * Reset largest free area size statistic as needed, - * but only if we've actually allocated memory. - */ - if (addr != 0 - && curr_size > allocator->largest_free_area) { - allocator->largest_free_area = curr_size; - break; - } - } - - mutex_unlock(&allocator->lock); - - return addr; -} - -long memrar_allocator_free(struct memrar_allocator *allocator, - unsigned long addr) -{ - struct list_head *pos = NULL; - struct list_head *tmp = NULL; - struct list_head *dst = NULL; - - struct memrar_address_ranges *allocated = NULL; - struct memrar_address_range const *handle = NULL; - - unsigned long old_end = 0; - unsigned long new_chunk_size = 0; - - if (allocator == NULL) - return -EINVAL; - - if (addr == 0) - return 0; /* Ignore "free(0)". */ - - mutex_lock(&allocator->lock); - - /* Find the corresponding handle. */ - list_for_each_entry(allocated, - &allocator->allocated_list.list, - list) { - if (allocated->range.begin == addr) { - handle = &allocated->range; - break; - } - } - - /* No such buffer created by this allocator. */ - if (handle == NULL) { - mutex_unlock(&allocator->lock); - return -EFAULT; - } - - /* - * Coalesce adjacent chunks of memory if possible. - * - * @note This isn't full blown coalescing since we're only - * coalescing at most three chunks of memory. - */ - list_for_each_safe(pos, tmp, &allocator->free_list.list) { - /* @todo O(n) performance. Optimize. */ - - struct memrar_address_range * const chunk = - &list_entry(pos, - struct memrar_address_ranges, - list)->range; - - /* Extend size of existing free adjacent chunk. */ - if (chunk->end == handle->begin) { - /* - * Chunk "less than" than the one we're - * freeing is adjacent. - * - * Before: - * - * +-----+------+ - * |chunk|handle| - * +-----+------+ - * - * After: - * - * +------------+ - * | chunk | - * +------------+ - */ - - struct memrar_address_ranges const * const next = - list_entry(pos->next, - struct memrar_address_ranges, - list); - - chunk->end = handle->end; - - /* - * Now check if next free chunk is adjacent to - * the current extended free chunk. - * - * Before: - * - * +------------+----+ - * | chunk |next| - * +------------+----+ - * - * After: - * - * +-----------------+ - * | chunk | - * +-----------------+ - */ - if (!list_is_singular(pos) - && chunk->end == next->range.begin) { - chunk->end = next->range.end; - list_del(pos->next); - kfree(next); - } - - list_del(&allocated->list); - - new_chunk_size = chunk->end - chunk->begin; - - goto exit_memrar_free; - - } else if (handle->end == chunk->begin) { - /* - * Chunk "greater than" than the one we're - * freeing is adjacent. - * - * +------+-----+ - * |handle|chunk| - * +------+-----+ - * - * After: - * - * +------------+ - * | chunk | - * +------------+ - */ - - struct memrar_address_ranges const * const prev = - list_entry(pos->prev, - struct memrar_address_ranges, - list); - - chunk->begin = handle->begin; - - /* - * Now check if previous free chunk is - * adjacent to the current extended free - * chunk. - * - * - * Before: - * - * +----+------------+ - * |prev| chunk | - * +----+------------+ - * - * After: - * - * +-----------------+ - * | chunk | - * +-----------------+ - */ - if (!list_is_singular(pos) - && prev->range.end == chunk->begin) { - chunk->begin = prev->range.begin; - list_del(pos->prev); - kfree(prev); - } - - list_del(&allocated->list); - - new_chunk_size = chunk->end - chunk->begin; - - goto exit_memrar_free; - - } else if (chunk->end < handle->begin - && chunk->end > old_end) { - /* Keep track of where the entry could be - * potentially moved from the "allocated" list - * to the "free" list if coalescing doesn't - * occur, making sure the "free" list remains - * sorted. - */ - old_end = chunk->end; - dst = pos; - } - } - - /* - * Nothing to coalesce. - * - * Move the entry from the "allocated" list to the "free" - * list. - */ - list_move(&allocated->list, dst); - new_chunk_size = handle->end - handle->begin; - allocated = NULL; - -exit_memrar_free: - - if (new_chunk_size > allocator->largest_free_area) - allocator->largest_free_area = new_chunk_size; - - mutex_unlock(&allocator->lock); - - kfree(allocated); - - return 0; -} - - - -/* - Local Variables: - c-file-style: "linux" - End: -*/ diff --git a/drivers/staging/memrar/memrar_allocator.h b/drivers/staging/memrar/memrar_allocator.h deleted file mode 100644 index 0b80dead710..00000000000 --- a/drivers/staging/memrar/memrar_allocator.h +++ /dev/null @@ -1,149 +0,0 @@ -/* - * Copyright (C) 2010 Intel Corporation. All rights reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General - * Public License as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be - * useful, but WITHOUT ANY WARRANTY; without even the implied - * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR - * PURPOSE. See the GNU General Public License for more details. - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the Free - * Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 02111-1307, USA. - * The full GNU General Public License is included in this - * distribution in the file called COPYING. - */ - -#ifndef MEMRAR_ALLOCATOR_H -#define MEMRAR_ALLOCATOR_H - - -#include -#include -#include -#include - - -/** - * struct memrar_address_range - struct that describes a memory range - * @begin: Beginning of available address range. - * @end: End of available address range, one past the end, - * i.e. [begin, end). - */ -struct memrar_address_range { -/* private: internal use only */ - unsigned long begin; - unsigned long end; -}; - -/** - * struct memrar_address_ranges - list of areas of memory. - * @list: Linked list of address ranges. - * @range: Memory address range corresponding to given list node. - */ -struct memrar_address_ranges { -/* private: internal use only */ - struct list_head list; - struct memrar_address_range range; -}; - -/** - * struct memrar_allocator - encapsulation of the memory allocator state - * @lock: Lock used to synchronize access to the memory - * allocator state. - * @base: Base (start) address of the allocator memory - * space. - * @capacity: Size of the allocator memory space in bytes. - * @block_size: The size in bytes of individual blocks within - * the allocator memory space. - * @largest_free_area: Largest free area of memory in the allocator - * in bytes. - * @allocated_list: List of allocated memory block address - * ranges. - * @free_list: List of free address ranges. - * - * This structure contains all memory allocator state, including the - * base address, capacity, free list, lock, etc. - */ -struct memrar_allocator { -/* private: internal use only */ - struct mutex lock; - unsigned long base; - size_t capacity; - size_t block_size; - size_t largest_free_area; - struct memrar_address_ranges allocated_list; - struct memrar_address_ranges free_list; -}; - -/** - * memrar_create_allocator() - create a memory allocator - * @base: Address at which the memory allocator begins. - * @capacity: Desired size of the memory allocator. This value must - * be larger than the block_size, ideally more than twice - * as large since there wouldn't be much point in using a - * memory allocator otherwise. - * @block_size: The size of individual blocks within the memory - * allocator. This value must smaller than the - * capacity. - * - * Create a memory allocator with the given capacity and block size. - * The capacity will be reduced to be a multiple of the block size, if - * necessary. - * - * Returns an instance of the memory allocator, if creation succeeds, - * otherwise zero if creation fails. Failure may occur if not enough - * kernel memory exists to create the memrar_allocator instance - * itself, or if the capacity and block_size arguments are not - * compatible or make sense. - */ -struct memrar_allocator *memrar_create_allocator(unsigned long base, - size_t capacity, - size_t block_size); - -/** - * memrar_destroy_allocator() - destroy allocator - * @allocator: The allocator being destroyed. - * - * Reclaim resources held by the memory allocator. The caller must - * explicitly free all memory reserved by memrar_allocator_alloc() - * prior to calling this function. Otherwise leaks will occur. - */ -void memrar_destroy_allocator(struct memrar_allocator *allocator); - -/** - * memrar_allocator_alloc() - reserve an area of memory of given size - * @allocator: The allocator instance being used to reserve buffer. - * @size: The size in bytes of the buffer to allocate. - * - * This functions reserves an area of memory managed by the given - * allocator. It returns zero if allocation was not possible. - * Failure may occur if the allocator no longer has space available. - */ -unsigned long memrar_allocator_alloc(struct memrar_allocator *allocator, - size_t size); - -/** - * memrar_allocator_free() - release buffer starting at given address - * @allocator: The allocator instance being used to release the buffer. - * @address: The address of the buffer being released. - * - * Release an area of memory starting at the given address. Failure - * could occur if the given address is not in the address space - * managed by the allocator. Returns zero on success or an errno - * (negative value) on failure. - */ -long memrar_allocator_free(struct memrar_allocator *allocator, - unsigned long address); - -#endif /* MEMRAR_ALLOCATOR_H */ - - -/* - Local Variables: - c-file-style: "linux" - End: -*/ diff --git a/drivers/staging/memrar/memrar_handler.c b/drivers/staging/memrar/memrar_handler.c deleted file mode 100644 index cfcaa8e5b8e..00000000000 --- a/drivers/staging/memrar/memrar_handler.c +++ /dev/null @@ -1,1007 +0,0 @@ -/* - * memrar_handler 1.0: An Intel restricted access region handler device - * - * Copyright (C) 2010 Intel Corporation. All rights reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General - * Public License as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be - * useful, but WITHOUT ANY WARRANTY; without even the implied - * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR - * PURPOSE. See the GNU General Public License for more details. - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the Free - * Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 02111-1307, USA. - * The full GNU General Public License is included in this - * distribution in the file called COPYING. - * - * ------------------------------------------------------------------- - * - * Moorestown restricted access regions (RAR) provide isolated - * areas of main memory that are only acceessible by authorized - * devices. - * - * The Intel Moorestown RAR handler module exposes a kernel space - * RAR memory management mechanism. It is essentially a - * RAR-specific allocator. - * - * Besides providing RAR buffer management, the RAR handler also - * behaves in many ways like an OS virtual memory manager. For - * example, the RAR "handles" created by the RAR handler are - * analogous to user space virtual addresses. - * - * RAR memory itself is never accessed directly by the RAR - * handler. - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "memrar.h" -#include "memrar_allocator.h" - - -#define MEMRAR_VER "1.0" - -/* - * Moorestown supports three restricted access regions. - * - * We only care about the first two, video and audio. The third, - * reserved for Chaabi and the P-unit, will be handled by their - * respective drivers. - */ -#define MRST_NUM_RAR 2 - -/* ---------------- -------------------- ------------------- */ - -/** - * struct memrar_buffer_info - struct that keeps track of all RAR buffers - * @list: Linked list of memrar_buffer_info objects. - * @buffer: Core RAR buffer information. - * @refcount: Reference count. - * @owner: File handle corresponding to process that reserved the - * block of memory in RAR. This will be zero for buffers - * allocated by other drivers instead of by a user space - * process. - * - * This structure encapsulates a link list of RAR buffers, as well as - * other characteristics specific to a given list node, such as the - * reference count on the corresponding RAR buffer. - */ -struct memrar_buffer_info { - struct list_head list; - struct RAR_buffer buffer; - struct kref refcount; - struct file *owner; -}; - -/** - * struct memrar_rar_info - characteristics of a given RAR - * @base: Base bus address of the RAR. - * @length: Length of the RAR. - * @iobase: Virtual address of RAR mapped into kernel. - * @allocator: Allocator associated with the RAR. Note the allocator - * "capacity" may be smaller than the RAR length if the - * length is not a multiple of the configured allocator - * block size. - * @buffers: Table that keeps track of all reserved RAR buffers. - * @lock: Lock used to synchronize access to RAR-specific data - * structures. - * - * Each RAR has an associated memrar_rar_info structure that describes - * where in memory the RAR is located, how large it is, and a list of - * reserved RAR buffers inside that RAR. Each RAR also has a mutex - * associated with it to reduce lock contention when operations on - * multiple RARs are performed in parallel. - */ -struct memrar_rar_info { - dma_addr_t base; - unsigned long length; - void __iomem *iobase; - struct memrar_allocator *allocator; - struct memrar_buffer_info buffers; - struct mutex lock; - int allocated; /* True if we own this RAR */ -}; - -/* - * Array of RAR characteristics. - */ -static struct memrar_rar_info memrars[MRST_NUM_RAR]; - -/* ---------------- -------------------- ------------------- */ - -/* Validate RAR type. */ -static inline int memrar_is_valid_rar_type(u32 type) -{ - return type == RAR_TYPE_VIDEO || type == RAR_TYPE_AUDIO; -} - -/* Check if an address/handle falls with the given RAR memory range. */ -static inline int memrar_handle_in_range(struct memrar_rar_info *rar, - u32 vaddr) -{ - unsigned long const iobase = (unsigned long) (rar->iobase); - return (vaddr >= iobase && vaddr < iobase + rar->length); -} - -/* Retrieve RAR information associated with the given handle. */ -static struct memrar_rar_info *memrar_get_rar_info(u32 vaddr) -{ - int i; - for (i = 0; i < MRST_NUM_RAR; ++i) { - struct memrar_rar_info * const rar = &memrars[i]; - if (memrar_handle_in_range(rar, vaddr)) - return rar; - } - - return NULL; -} - -/** - * memrar_get_bus address - handle to bus address - * - * Retrieve bus address from given handle. - * - * Returns address corresponding to given handle. Zero if handle is - * invalid. - */ -static dma_addr_t memrar_get_bus_address( - struct memrar_rar_info *rar, - u32 vaddr) -{ - unsigned long const iobase = (unsigned long) (rar->iobase); - - if (!memrar_handle_in_range(rar, vaddr)) - return 0; - - /* - * An assumption is made that the virtual address offset is - * the same as the bus address offset, at least based on the - * way this driver is implemented. For example, vaddr + 2 == - * baddr + 2. - * - * @todo Is that a valid assumption? - */ - return rar->base + (vaddr - iobase); -} - -/** - * memrar_get_physical_address - handle to physical address - * - * Retrieve physical address from given handle. - * - * Returns address corresponding to given handle. Zero if handle is - * invalid. - */ -static dma_addr_t memrar_get_physical_address( - struct memrar_rar_info *rar, - u32 vaddr) -{ - /* - * @todo This assumes that the bus address and physical - * address are the same. That is true for Moorestown - * but not necessarily on other platforms. This - * deficiency should be addressed at some point. - */ - return memrar_get_bus_address(rar, vaddr); -} - -/** - * memrar_release_block - release a block to the pool - * @kref: kref of block - * - * Core block release code. A node has hit zero references so can - * be released and the lists must be updated. - * - * Note: This code removes the node from a list. Make sure any list - * iteration is performed using list_for_each_safe(). - */ -static void memrar_release_block_i(struct kref *ref) -{ - /* - * Last reference is being released. Remove from the table, - * and reclaim resources. - */ - - struct memrar_buffer_info * const node = - container_of(ref, struct memrar_buffer_info, refcount); - - struct RAR_block_info * const user_info = - &node->buffer.info; - - struct memrar_allocator * const allocator = - memrars[user_info->type].allocator; - - list_del(&node->list); - - memrar_allocator_free(allocator, user_info->handle); - - kfree(node); -} - -/** - * memrar_init_rar_resources - configure a RAR - * @rarnum: rar that has been allocated - * @devname: name of our device - * - * Initialize RAR parameters, such as bus addresses, etc and make - * the resource accessible. - */ -static int memrar_init_rar_resources(int rarnum, char const *devname) -{ - /* ---- Sanity Checks ---- - * 1. RAR bus addresses in both Lincroft and Langwell RAR - * registers should be the same. - * a. There's no way we can do this through IA. - * - * 2. Secure device ID in Langwell RAR registers should be set - * appropriately, e.g. only LPE DMA for the audio RAR, and - * security for the other Langwell based RAR registers. - * a. There's no way we can do this through IA. - * - * 3. Audio and video RAR registers and RAR access should be - * locked down. If not, enable RAR access control. Except - * for debugging purposes, there is no reason for them to - * be unlocked. - * a. We can only do this for the Lincroft (IA) side. - * - * @todo Should the RAR handler driver even be aware of audio - * and video RAR settings? - */ - - /* - * RAR buffer block size. - * - * We choose it to be the size of a page to simplify the - * /dev/memrar mmap() implementation and usage. Otherwise - * paging is not involved once an RAR is locked down. - */ - static size_t const RAR_BLOCK_SIZE = PAGE_SIZE; - - dma_addr_t low, high; - struct memrar_rar_info * const rar = &memrars[rarnum]; - - BUG_ON(MRST_NUM_RAR != ARRAY_SIZE(memrars)); - BUG_ON(!memrar_is_valid_rar_type(rarnum)); - BUG_ON(rar->allocated); - - if (rar_get_address(rarnum, &low, &high) != 0) - /* No RAR is available. */ - return -ENODEV; - - if (low == 0 || high == 0) { - rar->base = 0; - rar->length = 0; - rar->iobase = NULL; - rar->allocator = NULL; - return -ENOSPC; - } - - /* - * @todo Verify that LNC and LNW RAR register contents - * addresses, security, etc are compatible and - * consistent). - */ - - rar->length = high - low + 1; - - /* Claim RAR memory as our own. */ - if (request_mem_region(low, rar->length, devname) == NULL) { - rar->length = 0; - pr_err("%s: Unable to claim RAR[%d] memory.\n", - devname, rarnum); - pr_err("%s: RAR[%d] disabled.\n", devname, rarnum); - return -EBUSY; - } - - rar->base = low; - - /* - * Now map it into the kernel address space. - * - * Note that the RAR memory may only be accessed by IA - * when debugging. Otherwise attempts to access the - * RAR memory when it is locked down will result in - * behavior similar to writing to /dev/null and - * reading from /dev/zero. This behavior is enforced - * by the hardware. Even if we don't access the - * memory, mapping it into the kernel provides us with - * a convenient RAR handle to bus address mapping. - */ - rar->iobase = ioremap_nocache(rar->base, rar->length); - if (rar->iobase == NULL) { - pr_err("%s: Unable to map RAR memory.\n", devname); - release_mem_region(low, rar->length); - return -ENOMEM; - } - - /* Initialize corresponding memory allocator. */ - rar->allocator = memrar_create_allocator((unsigned long) rar->iobase, - rar->length, RAR_BLOCK_SIZE); - if (rar->allocator == NULL) { - iounmap(rar->iobase); - release_mem_region(low, rar->length); - return -ENOMEM; - } - - pr_info("%s: BRAR[%d] bus address range = [0x%lx, 0x%lx]\n", - devname, rarnum, (unsigned long) low, (unsigned long) high); - - pr_info("%s: BRAR[%d] size = %zu KiB\n", - devname, rarnum, rar->allocator->capacity / 1024); - - rar->allocated = 1; - return 0; -} - -/** - * memrar_fini_rar_resources - free up RAR resources - * - * Finalize RAR resources. Free up the resource tables, hand the memory - * back to the kernel, unmap the device and release the address space. - */ -static void memrar_fini_rar_resources(void) -{ - int z; - struct memrar_buffer_info *pos; - struct memrar_buffer_info *tmp; - - /* - * @todo Do we need to hold a lock at this point in time? - * (module initialization failure or exit?) - */ - - for (z = MRST_NUM_RAR; z-- != 0; ) { - struct memrar_rar_info * const rar = &memrars[z]; - - if (!rar->allocated) - continue; - - /* Clean up remaining resources. */ - - list_for_each_entry_safe(pos, - tmp, - &rar->buffers.list, - list) { - kref_put(&pos->refcount, memrar_release_block_i); - } - - memrar_destroy_allocator(rar->allocator); - rar->allocator = NULL; - - iounmap(rar->iobase); - release_mem_region(rar->base, rar->length); - - rar->iobase = NULL; - rar->base = 0; - rar->length = 0; - - unregister_rar(z); - } -} - -/** - * memrar_reserve_block - handle an allocation request - * @request: block being requested - * @filp: owner it is tied to - * - * Allocate a block of the requested RAR. If successful return the - * request object filled in and zero, if not report an error code - */ - -static long memrar_reserve_block(struct RAR_buffer *request, - struct file *filp) -{ - struct RAR_block_info * const rinfo = &request->info; - struct RAR_buffer *buffer; - struct memrar_buffer_info *buffer_info; - u32 handle; - struct memrar_rar_info *rar = NULL; - - /* Prevent array overflow. */ - if (!memrar_is_valid_rar_type(rinfo->type)) - return -EINVAL; - - rar = &memrars[rinfo->type]; - if (!rar->allocated) - return -ENODEV; - - /* Reserve memory in RAR. */ - handle = memrar_allocator_alloc(rar->allocator, rinfo->size); - if (handle == 0) - return -ENOMEM; - - buffer_info = kmalloc(sizeof(*buffer_info), GFP_KERNEL); - - if (buffer_info == NULL) { - memrar_allocator_free(rar->allocator, handle); - return -ENOMEM; - } - - buffer = &buffer_info->buffer; - buffer->info.type = rinfo->type; - buffer->info.size = rinfo->size; - - /* Memory handle corresponding to the bus address. */ - buffer->info.handle = handle; - buffer->bus_address = memrar_get_bus_address(rar, handle); - - /* - * Keep track of owner so that we can later cleanup if - * necessary. - */ - buffer_info->owner = filp; - - kref_init(&buffer_info->refcount); - - mutex_lock(&rar->lock); - list_add(&buffer_info->list, &rar->buffers.list); - mutex_unlock(&rar->lock); - - rinfo->handle = buffer->info.handle; - request->bus_address = buffer->bus_address; - - return 0; -} - -/** - * memrar_release_block - release a RAR block - * @addr: address in RAR space - * - * Release a previously allocated block. Releases act on complete - * blocks, partially freeing a block is not supported - */ - -static long memrar_release_block(u32 addr) -{ - struct memrar_buffer_info *pos; - struct memrar_buffer_info *tmp; - struct memrar_rar_info * const rar = memrar_get_rar_info(addr); - long result = -EINVAL; - - if (rar == NULL) - return -ENOENT; - - mutex_lock(&rar->lock); - - /* - * Iterate through the buffer list to find the corresponding - * buffer to be released. - */ - list_for_each_entry_safe(pos, - tmp, - &rar->buffers.list, - list) { - struct RAR_block_info * const info = - &pos->buffer.info; - - /* - * Take into account handle offsets that may have been - * added to the base handle, such as in the following - * scenario: - * - * u32 handle = base + offset; - * rar_handle_to_bus(handle); - * rar_release(handle); - */ - if (addr >= info->handle - && addr < (info->handle + info->size) - && memrar_is_valid_rar_type(info->type)) { - kref_put(&pos->refcount, memrar_release_block_i); - result = 0; - break; - } - } - - mutex_unlock(&rar->lock); - - return result; -} - -/** - * memrar_get_stats - read statistics for a RAR - * @r: statistics to be filled in - * - * Returns the statistics data for the RAR, or an error code if - * the request cannot be completed - */ -static long memrar_get_stat(struct RAR_stat *r) -{ - struct memrar_allocator *allocator; - - if (!memrar_is_valid_rar_type(r->type)) - return -EINVAL; - - if (!memrars[r->type].allocated) - return -ENODEV; - - allocator = memrars[r->type].allocator; - - BUG_ON(allocator == NULL); - - /* - * Allocator capacity doesn't change over time. No - * need to synchronize. - */ - r->capacity = allocator->capacity; - - mutex_lock(&allocator->lock); - r->largest_block_size = allocator->largest_free_area; - mutex_unlock(&allocator->lock); - return 0; -} - -/** - * memrar_ioctl - ioctl callback - * @filp: file issuing the request - * @cmd: command - * @arg: pointer to control information - * - * Perform one of the ioctls supported by the memrar device - */ - -static long memrar_ioctl(struct file *filp, - unsigned int cmd, - unsigned long arg) -{ - void __user *argp = (void __user *)arg; - long result = 0; - - struct RAR_buffer buffer; - struct RAR_block_info * const request = &buffer.info; - struct RAR_stat rar_info; - u32 rar_handle; - - switch (cmd) { - case RAR_HANDLER_RESERVE: - if (copy_from_user(request, - argp, - sizeof(*request))) - return -EFAULT; - - result = memrar_reserve_block(&buffer, filp); - if (result != 0) - return result; - - return copy_to_user(argp, request, sizeof(*request)); - - case RAR_HANDLER_RELEASE: - if (copy_from_user(&rar_handle, - argp, - sizeof(rar_handle))) - return -EFAULT; - - return memrar_release_block(rar_handle); - - case RAR_HANDLER_STAT: - if (copy_from_user(&rar_info, - argp, - sizeof(rar_info))) - return -EFAULT; - - /* - * Populate the RAR_stat structure based on the RAR - * type given by the user - */ - if (memrar_get_stat(&rar_info) != 0) - return -EINVAL; - - /* - * @todo Do we need to verify destination pointer - * "argp" is non-zero? Is that already done by - * copy_to_user()? - */ - return copy_to_user(argp, - &rar_info, - sizeof(rar_info)) ? -EFAULT : 0; - - default: - return -ENOTTY; - } - - return 0; -} - -/** - * memrar_mmap - mmap helper for deubgging - * @filp: handle doing the mapping - * @vma: memory area - * - * Support the mmap operation on the RAR space for debugging systems - * when the memory is not locked down. - */ - -static int memrar_mmap(struct file *filp, struct vm_area_struct *vma) -{ - /* - * This mmap() implementation is predominantly useful for - * debugging since the CPU will be prevented from accessing - * RAR memory by the hardware when RAR is properly locked - * down. - * - * In order for this implementation to be useful RAR memory - * must be not be locked down. However, we only want to do - * that when debugging. DO NOT leave RAR memory unlocked in a - * deployed device that utilizes RAR. - */ - - size_t const size = vma->vm_end - vma->vm_start; - - /* Users pass the RAR handle as the mmap() offset parameter. */ - unsigned long const handle = vma->vm_pgoff << PAGE_SHIFT; - - struct memrar_rar_info * const rar = memrar_get_rar_info(handle); - unsigned long pfn; - - /* Only allow priviledged apps to go poking around this way */ - if (!capable(CAP_SYS_RAWIO)) - return -EPERM; - - /* Invalid RAR handle or size passed to mmap(). */ - if (rar == NULL - || handle == 0 - || size > (handle - (unsigned long) rar->iobase)) - return -EINVAL; - - /* - * Retrieve physical address corresponding to the RAR handle, - * and convert it to a page frame. - */ - pfn = memrar_get_physical_address(rar, handle) >> PAGE_SHIFT; - - - pr_debug("memrar: mapping RAR range [0x%lx, 0x%lx) into user space.\n", - handle, - handle + size); - - /* - * Map RAR memory into user space. This is really only useful - * for debugging purposes since the memory won't be - * accessible, i.e. reads return zero and writes are ignored, - * when RAR access control is enabled. - */ - if (remap_pfn_range(vma, - vma->vm_start, - pfn, - size, - vma->vm_page_prot)) - return -EAGAIN; - - /* vma->vm_ops = &memrar_mem_ops; */ - - return 0; -} - -/** - * memrar_open - device open method - * @inode: inode to open - * @filp: file handle - * - * As we support multiple arbitary opens there is no work to be done - * really. - */ - -static int memrar_open(struct inode *inode, struct file *filp) -{ - nonseekable_open(inode, filp); - return 0; -} - -/** - * memrar_release - close method for miscev - * @inode: inode of device - * @filp: handle that is going away - * - * Free up all the regions that belong to this file handle. We use - * the handle as a natural Linux style 'lifetime' indicator and to - * ensure resources are not leaked when their owner explodes in an - * unplanned fashion. - */ - -static int memrar_release(struct inode *inode, struct file *filp) -{ - /* Free all regions associated with the given file handle. */ - - struct memrar_buffer_info *pos; - struct memrar_buffer_info *tmp; - int z; - - for (z = 0; z != MRST_NUM_RAR; ++z) { - struct memrar_rar_info * const rar = &memrars[z]; - - mutex_lock(&rar->lock); - - list_for_each_entry_safe(pos, - tmp, - &rar->buffers.list, - list) { - if (filp == pos->owner) - kref_put(&pos->refcount, - memrar_release_block_i); - } - - mutex_unlock(&rar->lock); - } - - return 0; -} - -/** - * rar_reserve - reserve RAR memory - * @buffers: buffers to reserve - * @count: number wanted - * - * Reserve a series of buffers in the RAR space. Returns the number of - * buffers successfully allocated - */ - -size_t rar_reserve(struct RAR_buffer *buffers, size_t count) -{ - struct RAR_buffer * const end = - (buffers == NULL ? buffers : buffers + count); - struct RAR_buffer *i; - - size_t reserve_count = 0; - - for (i = buffers; i != end; ++i) { - if (memrar_reserve_block(i, NULL) == 0) - ++reserve_count; - else - i->bus_address = 0; - } - - return reserve_count; -} -EXPORT_SYMBOL(rar_reserve); - -/** - * rar_release - return RAR buffers - * @buffers: buffers to release - * @size: size of released block - * - * Return a set of buffers to the RAR pool - */ - -size_t rar_release(struct RAR_buffer *buffers, size_t count) -{ - struct RAR_buffer * const end = - (buffers == NULL ? buffers : buffers + count); - struct RAR_buffer *i; - - size_t release_count = 0; - - for (i = buffers; i != end; ++i) { - u32 * const handle = &i->info.handle; - if (memrar_release_block(*handle) == 0) { - /* - * @todo We assume we should do this each time - * the ref count is decremented. Should - * we instead only do this when the ref - * count has dropped to zero, and the - * buffer has been completely - * released/unmapped? - */ - *handle = 0; - ++release_count; - } - } - - return release_count; -} -EXPORT_SYMBOL(rar_release); - -/** - * rar_handle_to_bus - RAR to bus address - * @buffers: RAR buffer structure - * @count: number of buffers to convert - * - * Turn a list of RAR handle mappings into actual bus addresses. Note - * that when the device is locked down the bus addresses in question - * are not CPU accessible. - */ - -size_t rar_handle_to_bus(struct RAR_buffer *buffers, size_t count) -{ - struct RAR_buffer * const end = - (buffers == NULL ? buffers : buffers + count); - struct RAR_buffer *i; - struct memrar_buffer_info *pos; - - size_t conversion_count = 0; - - /* - * Find all bus addresses corresponding to the given handles. - * - * @todo Not liking this nested loop. Optimize. - */ - for (i = buffers; i != end; ++i) { - struct memrar_rar_info * const rar = - memrar_get_rar_info(i->info.handle); - - /* - * Check if we have a bogus handle, and then continue - * with remaining buffers. - */ - if (rar == NULL) { - i->bus_address = 0; - continue; - } - - mutex_lock(&rar->lock); - - list_for_each_entry(pos, &rar->buffers.list, list) { - struct RAR_block_info * const user_info = - &pos->buffer.info; - - /* - * Take into account handle offsets that may - * have been added to the base handle, such as - * in the following scenario: - * - * u32 handle = base + offset; - * rar_handle_to_bus(handle); - */ - - if (i->info.handle >= user_info->handle - && i->info.handle < (user_info->handle - + user_info->size)) { - u32 const offset = - i->info.handle - user_info->handle; - - i->info.type = user_info->type; - i->info.size = user_info->size - offset; - i->bus_address = - pos->buffer.bus_address - + offset; - - /* Increment the reference count. */ - kref_get(&pos->refcount); - - ++conversion_count; - break; - } else { - i->bus_address = 0; - } - } - - mutex_unlock(&rar->lock); - } - - return conversion_count; -} -EXPORT_SYMBOL(rar_handle_to_bus); - -static const struct file_operations memrar_fops = { - .owner = THIS_MODULE, - .unlocked_ioctl = memrar_ioctl, - .mmap = memrar_mmap, - .open = memrar_open, - .release = memrar_release, - .llseek = no_llseek, -}; - -static struct miscdevice memrar_miscdev = { - .minor = MISC_DYNAMIC_MINOR, /* dynamic allocation */ - .name = "memrar", /* /dev/memrar */ - .fops = &memrar_fops -}; - -static char const banner[] __initdata = - KERN_INFO - "Intel RAR Handler: " MEMRAR_VER " initialized.\n"; - -/** - * memrar_registration_callback - RAR obtained - * @rar: RAR number - * - * We have been granted ownership of the RAR. Add it to our memory - * management tables - */ - -static int memrar_registration_callback(unsigned long rar) -{ - /* - * We initialize the RAR parameters early on so that we can - * discontinue memrar device initialization and registration - * if suitably configured RARs are not available. - */ - return memrar_init_rar_resources(rar, memrar_miscdev.name); -} - -/** - * memrar_init - initialise RAR support - * - * Initialise support for RAR handlers. This may get loaded before - * the RAR support is activated, but the callbacks on the registration - * will handle that situation for us anyway. - */ - -static int __init memrar_init(void) -{ - int err; - int i; - - printk(banner); - - /* - * Some delayed initialization is performed in this driver. - * Make sure resources that are used during driver clean-up - * (e.g. during driver's release() function) are fully - * initialized before first use. This is particularly - * important for the case when the delayed initialization - * isn't completed, leaving behind a partially initialized - * driver. - * - * Such a scenario can occur when RAR is not available on the - * platform, and the driver is release()d. - */ - for (i = 0; i != ARRAY_SIZE(memrars); ++i) { - struct memrar_rar_info * const rar = &memrars[i]; - mutex_init(&rar->lock); - INIT_LIST_HEAD(&rar->buffers.list); - } - - err = misc_register(&memrar_miscdev); - if (err) - return err; - - /* Now claim the two RARs we want */ - err = register_rar(0, memrar_registration_callback, 0); - if (err) - goto fail; - - err = register_rar(1, memrar_registration_callback, 1); - if (err == 0) - return 0; - - /* It is possible rar 0 registered and allocated resources then rar 1 - failed so do a full resource free */ - memrar_fini_rar_resources(); -fail: - misc_deregister(&memrar_miscdev); - return err; -} - -/** - * memrar_exit - unregister and unload - * - * Unregister the device and then unload any mappings and release - * the RAR resources - */ - -static void __exit memrar_exit(void) -{ - misc_deregister(&memrar_miscdev); - memrar_fini_rar_resources(); -} - - -module_init(memrar_init); -module_exit(memrar_exit); - - -MODULE_AUTHOR("Ossama Othman "); -MODULE_DESCRIPTION("Intel Restricted Access Region Handler"); -MODULE_LICENSE("GPL"); -MODULE_VERSION(MEMRAR_VER); - - - -/* - Local Variables: - c-file-style: "linux" - End: -*/ -- 2.20.1