From ae883cab9457aad0fb3342249e1207873d3b64de Mon Sep 17 00:00:00 2001 From: John Rose Date: Wed, 8 Nov 2006 10:07:30 -0600 Subject: [PATCH] [POWERPC] pseries: Force 4k update_flash block and list sizes The enablement of 64k pages on pseries platforms exposed a bug in the RTAS mechanism for updating firmware. RTAS assumes 4k for flash block and list sizes, and use of any other sizes results in a failure, even though PAPR does not specify any such requirement. This patch changes the rtas_flash module to force the use of 4k memory block and list sizes when preparing and sending a firmware image to RTAS. The rtas_flash function now uses a slab cache of 4k blocks with 4k alignment, rather than get_zeroed_page(), to allocate the memory for the flash blocks and lists. The 4k alignment requirement is specified in PAPR. Signed-off-by: John Rose Signed-off-by: Paul Mackerras --- arch/powerpc/kernel/rtas_flash.c | 47 +++++++++++++++++++++++++------- 1 file changed, 37 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/kernel/rtas_flash.c b/arch/powerpc/kernel/rtas_flash.c index 1442b63a75da..6f6fc977cb39 100644 --- a/arch/powerpc/kernel/rtas_flash.c +++ b/arch/powerpc/kernel/rtas_flash.c @@ -72,6 +72,10 @@ #define VALIDATE_BUF_SIZE 4096 #define RTAS_MSG_MAXLEN 64 +/* Quirk - RTAS requires 4k list length and block size */ +#define RTAS_BLKLIST_LENGTH 4096 +#define RTAS_BLK_SIZE 4096 + struct flash_block { char *data; unsigned long length; @@ -83,7 +87,7 @@ struct flash_block { * into a version/length and translate the pointers * to absolute. */ -#define FLASH_BLOCKS_PER_NODE ((PAGE_SIZE - 16) / sizeof(struct flash_block)) +#define FLASH_BLOCKS_PER_NODE ((RTAS_BLKLIST_LENGTH - 16) / sizeof(struct flash_block)) struct flash_block_list { unsigned long num_blocks; struct flash_block_list *next; @@ -96,6 +100,9 @@ struct flash_block_list_header { /* just the header of flash_block_list */ static struct flash_block_list_header rtas_firmware_flash_list = {0, NULL}; +/* Use slab cache to guarantee 4k alignment */ +static kmem_cache_t *flash_block_cache = NULL; + #define FLASH_BLOCK_LIST_VERSION (1UL) /* Local copy of the flash block list. @@ -153,7 +160,7 @@ static int flash_list_valid(struct flash_block_list *flist) return FLASH_IMG_NULL_DATA; } block_size = f->blocks[i].length; - if (block_size <= 0 || block_size > PAGE_SIZE) { + if (block_size <= 0 || block_size > RTAS_BLK_SIZE) { return FLASH_IMG_BAD_LEN; } image_size += block_size; @@ -177,9 +184,9 @@ static void free_flash_list(struct flash_block_list *f) while (f) { for (i = 0; i < f->num_blocks; i++) - free_page((unsigned long)(f->blocks[i].data)); + kmem_cache_free(flash_block_cache, f->blocks[i].data); next = f->next; - free_page((unsigned long)f); + kmem_cache_free(flash_block_cache, f); f = next; } } @@ -278,6 +285,12 @@ static ssize_t rtas_flash_read(struct file *file, char __user *buf, return msglen; } +/* constructor for flash_block_cache */ +void rtas_block_ctor(void *ptr, kmem_cache_t *cache, unsigned long flags) +{ + memset(ptr, 0, RTAS_BLK_SIZE); +} + /* We could be much more efficient here. But to keep this function * simple we allocate a page to the block list no matter how small the * count is. If the system is low on memory it will be just as well @@ -302,7 +315,7 @@ static ssize_t rtas_flash_write(struct file *file, const char __user *buffer, * proc file */ if (uf->flist == NULL) { - uf->flist = (struct flash_block_list *) get_zeroed_page(GFP_KERNEL); + uf->flist = kmem_cache_alloc(flash_block_cache, GFP_KERNEL); if (!uf->flist) return -ENOMEM; } @@ -313,21 +326,21 @@ static ssize_t rtas_flash_write(struct file *file, const char __user *buffer, next_free = fl->num_blocks; if (next_free == FLASH_BLOCKS_PER_NODE) { /* Need to allocate another block_list */ - fl->next = (struct flash_block_list *)get_zeroed_page(GFP_KERNEL); + fl->next = kmem_cache_alloc(flash_block_cache, GFP_KERNEL); if (!fl->next) return -ENOMEM; fl = fl->next; next_free = 0; } - if (count > PAGE_SIZE) - count = PAGE_SIZE; - p = (char *)get_zeroed_page(GFP_KERNEL); + if (count > RTAS_BLK_SIZE) + count = RTAS_BLK_SIZE; + p = kmem_cache_alloc(flash_block_cache, GFP_KERNEL); if (!p) return -ENOMEM; if(copy_from_user(p, buffer, count)) { - free_page((unsigned long)p); + kmem_cache_free(flash_block_cache, p); return -EFAULT; } fl->blocks[next_free].data = p; @@ -791,6 +804,16 @@ int __init rtas_flash_init(void) goto cleanup; rtas_flash_term_hook = rtas_flash_firmware; + + flash_block_cache = kmem_cache_create("rtas_flash_cache", + RTAS_BLK_SIZE, RTAS_BLK_SIZE, 0, + rtas_block_ctor, NULL); + if (!flash_block_cache) { + printk(KERN_ERR "%s: failed to create block cache\n", + __FUNCTION__); + rc = -ENOMEM; + goto cleanup; + } return 0; cleanup: @@ -805,6 +828,10 @@ cleanup: void __exit rtas_flash_cleanup(void) { rtas_flash_term_hook = NULL; + + if (flash_block_cache) + kmem_cache_destroy(flash_block_cache); + remove_flash_pde(firmware_flash_pde); remove_flash_pde(firmware_update_pde); remove_flash_pde(validate_pde); -- 2.20.1