diff options
| -rw-r--r-- | drivers/firmware/efi/efi.c | 21 | ||||
| -rw-r--r-- | include/linux/efi.h | 3 |
2 files changed, 20 insertions, 4 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 80b11521627a..4c46ff6f2242 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -997,8 +997,8 @@ static int __init efi_memreserve_map_root(void) int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) { struct linux_efi_memreserve *rsv; - int rsvsize = EFI_MEMRESERVE_SIZE(1); - int rc; + unsigned long prsv; + int rc, index; if (efi_memreserve_root == (void *)ULONG_MAX) return -ENODEV; @@ -1009,11 +1009,24 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) return rc; } - rsv = kmalloc(rsvsize, GFP_ATOMIC); + /* first try to find a slot in an existing linked list entry */ + for (prsv = efi_memreserve_root->next; prsv; prsv = rsv->next) { + rsv = __va(prsv); + index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); + if (index < rsv->size) { + rsv->entry[index].base = addr; + rsv->entry[index].size = size; + + return 0; + } + } + + /* no slot found - allocate a new linked list entry */ + rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC); if (!rsv) return -ENOMEM; - rsv->size = 1; + rsv->size = EFI_MEMRESERVE_COUNT(PAGE_SIZE); atomic_set(&rsv->count, 1); rsv->entry[0].base = addr; rsv->entry[0].size = size; diff --git a/include/linux/efi.h b/include/linux/efi.h index 4f27640fdcdc..becd5d76a207 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1724,4 +1724,7 @@ struct linux_efi_memreserve { #define EFI_MEMRESERVE_SIZE(count) (sizeof(struct linux_efi_memreserve) + \ (count) * sizeof(((struct linux_efi_memreserve *)0)->entry[0])) +#define EFI_MEMRESERVE_COUNT(size) (((size) - sizeof(struct linux_efi_memreserve)) \ + / sizeof(((struct linux_efi_memreserve *)0)->entry[0])) + #endif /* _LINUX_EFI_H */ |