[PATCH 11/13] efi: Add tracking for dynamically allocated memmaps
From: Ard Biesheuvel
Date: Mon Jan 13 2020 - 12:23:50 EST
From: Dan Williams <dan.j.williams@xxxxxxxxx>
In preparation for fixing efi_memmap_alloc() leaks, add support for
recording whether the memmap was dynamically allocated from slab,
memblock, or is the original physical memmap provided by the platform.
Given this tracking is established in efi_memmap_alloc() and needs to be
carried to efi_memmap_install(), use 'struct efi_memory_map_data' to
convey the flags.
Some small cleanups result from this reorganization, specifically the
removal of local variables for 'phys' and 'size' that are already
tracked in @data.
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
arch/x86/platform/efi/efi.c | 10 +++++--
arch/x86/platform/efi/quirks.c | 23 +++++++---------
drivers/firmware/efi/fake_mem.c | 14 +++++-----
drivers/firmware/efi/memmap.c | 47 ++++++++++++++++++---------------
include/linux/efi.h | 11 +++++---
5 files changed, 56 insertions(+), 49 deletions(-)
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 4e46d2d24352..59f7f6d60cf6 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -304,10 +304,16 @@ static void __init efi_clean_memmap(void)
}
if (n_removal > 0) {
- u64 size = efi.memmap.nr_map - n_removal;
+ struct efi_memory_map_data data = {
+ .phys_map = efi.memmap.phys_map,
+ .desc_version = efi.memmap.desc_version,
+ .desc_size = efi.memmap.desc_size,
+ .size = data.desc_size * (efi.memmap.nr_map - n_removal),
+ .flags = 0,
+ };
pr_warn("Removing %d invalid memory map entries.\n", n_removal);
- efi_memmap_install(efi.memmap.phys_map, size);
+ efi_memmap_install(&data);
}
}
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index fe46ddf6c761..46807b7606da 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -243,7 +243,7 @@ EXPORT_SYMBOL_GPL(efi_query_variable_store);
*/
void __init efi_arch_mem_reserve(phys_addr_t addr, u64 size)
{
- phys_addr_t new_phys, new_size;
+ struct efi_memory_map_data data = { 0 };
struct efi_mem_range mr;
efi_memory_desc_t md;
int num_entries;
@@ -271,24 +271,21 @@ void __init efi_arch_mem_reserve(phys_addr_t addr, u64 size)
num_entries = efi_memmap_split_count(&md, &mr.range);
num_entries += efi.memmap.nr_map;
- new_size = efi.memmap.desc_size * num_entries;
-
- new_phys = efi_memmap_alloc(num_entries);
- if (!new_phys) {
+ if (efi_memmap_alloc(num_entries, &data) != 0) {
pr_err("Could not allocate boot services memmap\n");
return;
}
- new = early_memremap(new_phys, new_size);
+ new = early_memremap(data.phys_map, data.size);
if (!new) {
pr_err("Failed to map new boot services memmap\n");
return;
}
efi_memmap_insert(&efi.memmap, new, &mr);
- early_memunmap(new, new_size);
+ early_memunmap(new, data.size);
- efi_memmap_install(new_phys, num_entries);
+ efi_memmap_install(&data);
e820__range_update(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED);
e820__update_table(e820_table);
}
@@ -407,7 +404,7 @@ static void __init efi_unmap_pages(efi_memory_desc_t *md)
void __init efi_free_boot_services(void)
{
- phys_addr_t new_phys, new_size;
+ struct efi_memory_map_data data = { 0 };
efi_memory_desc_t *md;
int num_entries = 0;
void *new, *new_md;
@@ -462,14 +459,12 @@ void __init efi_free_boot_services(void)
if (!num_entries)
return;
- new_size = efi.memmap.desc_size * num_entries;
- new_phys = efi_memmap_alloc(num_entries);
- if (!new_phys) {
+ if (efi_memmap_alloc(num_entries, &data) != 0) {
pr_err("Failed to allocate new EFI memmap\n");
return;
}
- new = memremap(new_phys, new_size, MEMREMAP_WB);
+ new = memremap(data.phys_map, data.size, MEMREMAP_WB);
if (!new) {
pr_err("Failed to map new EFI memmap\n");
return;
@@ -493,7 +488,7 @@ void __init efi_free_boot_services(void)
memunmap(new);
- if (efi_memmap_install(new_phys, num_entries)) {
+ if (efi_memmap_install(&data) != 0) {
pr_err("Could not install new EFI memmap\n");
return;
}
diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
index bb9fc70d0cfa..a8d20568d532 100644
--- a/drivers/firmware/efi/fake_mem.c
+++ b/drivers/firmware/efi/fake_mem.c
@@ -36,9 +36,9 @@ static int __init cmp_fake_mem(const void *x1, const void *x2)
void __init efi_fake_memmap(void)
{
+ struct efi_memory_map_data data = { 0 };
int new_nr_map = efi.memmap.nr_map;
efi_memory_desc_t *md;
- phys_addr_t new_memmap_phy;
void *new_memmap;
int i;
@@ -55,15 +55,13 @@ void __init efi_fake_memmap(void)
}
/* allocate memory for new EFI memmap */
- new_memmap_phy = efi_memmap_alloc(new_nr_map);
- if (!new_memmap_phy)
+ if (efi_memmap_alloc(new_nr_map, &data) != 0)
return;
/* create new EFI memmap */
- new_memmap = early_memremap(new_memmap_phy,
- efi.memmap.desc_size * new_nr_map);
+ new_memmap = early_memremap(data.phys_map, data.size);
if (!new_memmap) {
- memblock_free(new_memmap_phy, efi.memmap.desc_size * new_nr_map);
+ memblock_free(data.phys_map, data.size);
return;
}
@@ -71,9 +69,9 @@ void __init efi_fake_memmap(void)
efi_memmap_insert(&efi.memmap, new_memmap, &efi_fake_mems[i]);
/* swap into new EFI memmap */
- early_memunmap(new_memmap, efi.memmap.desc_size * new_nr_map);
+ early_memunmap(new_memmap, data.size);
- efi_memmap_install(new_memmap_phy, new_nr_map);
+ efi_memmap_install(&data);
/* print new EFI memmap */
efi_print_memmap();
diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index 4f98eb12c172..04dfa56b994b 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -32,6 +32,7 @@ static phys_addr_t __init __efi_memmap_alloc_late(unsigned long size)
/**
* efi_memmap_alloc - Allocate memory for the EFI memory map
* @num_entries: Number of entries in the allocated map.
+ * @data: efi memmap installation parameters
*
* Depending on whether mm_init() has already been invoked or not,
* either memblock or "normal" page allocation is used.
@@ -39,14 +40,29 @@ static phys_addr_t __init __efi_memmap_alloc_late(unsigned long size)
* Returns the physical address of the allocated memory map on
* success, zero on failure.
*/
-phys_addr_t __init efi_memmap_alloc(unsigned int num_entries)
+int __init efi_memmap_alloc(unsigned int num_entries,
+ struct efi_memory_map_data *data)
{
- unsigned long size = num_entries * efi.memmap.desc_size;
-
- if (slab_is_available())
- return __efi_memmap_alloc_late(size);
+ /* Expect allocation parameters are zero initialized */
+ WARN_ON(data->phys_map || data->size);
+
+ data->size = num_entries * efi.memmap.desc_size;
+ data->desc_version = efi.memmap.desc_version;
+ data->desc_size = efi.memmap.desc_size;
+ data->flags &= ~(EFI_MEMMAP_SLAB | EFI_MEMMAP_MEMBLOCK);
+ data->flags |= efi.memmap.flags & EFI_MEMMAP_LATE;
+
+ if (slab_is_available()) {
+ data->flags |= EFI_MEMMAP_SLAB;
+ data->phys_map = __efi_memmap_alloc_late(data->size);
+ } else {
+ data->flags |= EFI_MEMMAP_MEMBLOCK;
+ data->phys_map = __efi_memmap_alloc_early(data->size);
+ }
- return __efi_memmap_alloc_early(size);
+ if (!data->phys_map)
+ return -ENOMEM;
+ return 0;
}
/**
@@ -64,8 +80,7 @@ phys_addr_t __init efi_memmap_alloc(unsigned int num_entries)
*
* Returns zero on success, a negative error code on failure.
*/
-static int __init
-__efi_memmap_init(struct efi_memory_map_data *data)
+static int __init __efi_memmap_init(struct efi_memory_map_data *data)
{
struct efi_memory_map map;
phys_addr_t phys_map;
@@ -184,8 +199,7 @@ int __init efi_memmap_init_late(phys_addr_t addr, unsigned long size)
/**
* efi_memmap_install - Install a new EFI memory map in efi.memmap
- * @addr: Physical address of the memory map
- * @nr_map: Number of entries in the memory map
+ * @ctx: map allocation parameters (address, size, flags)
*
* Unlike efi_memmap_init_*(), this function does not allow the caller
* to switch from early to late mappings. It simply uses the existing
@@ -193,20 +207,11 @@ int __init efi_memmap_init_late(phys_addr_t addr, unsigned long size)
*
* Returns zero on success, a negative error code on failure.
*/
-int __init efi_memmap_install(phys_addr_t addr, unsigned int nr_map)
+int __init efi_memmap_install(struct efi_memory_map_data *data)
{
- struct efi_memory_map_data data;
- unsigned long flags;
-
efi_memmap_unmap();
- data.phys_map = addr;
- data.size = efi.memmap.desc_size * nr_map;
- data.desc_version = efi.memmap.desc_version;
- data.desc_size = efi.memmap.desc_size;
- data.flags = efi.memmap.flags & EFI_MEMMAP_LATE;
-
- return __efi_memmap_init(&data);
+ return __efi_memmap_init(data);
}
/**
diff --git a/include/linux/efi.h b/include/linux/efi.h
index f117d68c314e..adbe421835c1 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -759,8 +759,8 @@ typedef union {
/*
* Architecture independent structure for describing a memory map for the
- * benefit of efi_memmap_init_early(), saving us the need to pass four
- * parameters.
+ * benefit of efi_memmap_init_early(), and for passing context between
+ * efi_memmap_alloc() and efi_memmap_install().
*/
struct efi_memory_map_data {
phys_addr_t phys_map;
@@ -778,6 +778,8 @@ struct efi_memory_map {
unsigned long desc_version;
unsigned long desc_size;
#define EFI_MEMMAP_LATE (1UL << 0)
+#define EFI_MEMMAP_MEMBLOCK (1UL << 1)
+#define EFI_MEMMAP_SLAB (1UL << 2)
unsigned long flags;
};
@@ -972,11 +974,12 @@ static inline efi_status_t efi_query_variable_store(u32 attributes,
#endif
extern void __iomem *efi_lookup_mapped_addr(u64 phys_addr);
-extern phys_addr_t __init efi_memmap_alloc(unsigned int num_entries);
+extern int __init efi_memmap_alloc(unsigned int num_entries,
+ struct efi_memory_map_data *data);
extern int __init efi_memmap_init_early(struct efi_memory_map_data *data);
extern int __init efi_memmap_init_late(phys_addr_t addr, unsigned long size);
extern void __init efi_memmap_unmap(void);
-extern int __init efi_memmap_install(phys_addr_t addr, unsigned int nr_map);
+extern int __init efi_memmap_install(struct efi_memory_map_data *data);
extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
struct range *range);
extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
--
2.20.1