Commit-ID: 5f0b0ecf043a5319e729c11a53bc8294df12dab3 Gitweb: https://git.kernel.org/tip/5f0b0ecf043a5319e729c11a53bc8294df12dab3 Author: Ard Biesheuvel <ard.biesheu...@linaro.org> AuthorDate: Thu, 29 Nov 2018 18:12:28 +0100 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Fri, 30 Nov 2018 09:10:31 +0100
efi: Permit multiple entries in persistent memreserve data structure In preparation of updating efi_mem_reserve_persistent() to cause less fragmentation when dealing with many persistent reservations, update the struct definition and the code that handles it currently so it can describe an arbitrary number of reservations using a single linked list entry. The actual optimization will be implemented in a subsequent patch. Tested-by: Marc Zyngier <marc.zyng...@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org> Cc: Andy Lutomirski <l...@kernel.org> Cc: Arend van Spriel <arend.vanspr...@broadcom.com> Cc: Bhupesh Sharma <bhsha...@redhat.com> Cc: Borislav Petkov <b...@alien8.de> Cc: Dave Hansen <dave.han...@intel.com> Cc: Eric Snowberg <eric.snowb...@oracle.com> Cc: Hans de Goede <hdego...@redhat.com> Cc: Joe Perches <j...@perches.com> Cc: Jon Hunter <jonath...@nvidia.com> Cc: Julien Thierry <julien.thie...@arm.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Matt Fleming <m...@codeblueprint.co.uk> Cc: Nathan Chancellor <natechancel...@gmail.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prak...@intel.com> Cc: Sedat Dilek <sedat.di...@gmail.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: YiFei Zhu <zhuyifei1...@gmail.com> Cc: linux-...@vger.kernel.org Link: http://lkml.kernel.org/r/20181129171230.18699-10-ard.biesheu...@linaro.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- drivers/firmware/efi/efi.c | 39 +++++++++++++++++++++++---------- drivers/firmware/efi/libstub/arm-stub.c | 2 +- include/linux/efi.h | 13 ++++++++--- 3 files changed, 38 insertions(+), 16 deletions(-) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 415849bab233..80b11521627a 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -602,21 +602,33 @@ int __init efi_apply_persistent_mem_reservations(void) while (prsv) { struct linux_efi_memreserve *rsv; - - /* reserve the entry itself */ - memblock_reserve(prsv, sizeof(*rsv)); - - rsv = early_memremap(prsv, sizeof(*rsv)); - if (rsv == NULL) { + u8 *p; + int i; + + /* + * Just map a full page: that is what we will get + * anyway, and it permits us to map the entire entry + * before knowing its size. + */ + p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE), + PAGE_SIZE); + if (p == NULL) { pr_err("Could not map UEFI memreserve entry!\n"); return -ENOMEM; } - if (rsv->size) - memblock_reserve(rsv->base, rsv->size); + rsv = (void *)(p + prsv % PAGE_SIZE); + + /* reserve the entry itself */ + memblock_reserve(prsv, EFI_MEMRESERVE_SIZE(rsv->size)); + + for (i = 0; i < atomic_read(&rsv->count); i++) { + memblock_reserve(rsv->entry[i].base, + rsv->entry[i].size); + } prsv = rsv->next; - early_memunmap(rsv, sizeof(*rsv)); + early_memunmap(p, PAGE_SIZE); } } @@ -985,6 +997,7 @@ 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; if (efi_memreserve_root == (void *)ULONG_MAX) @@ -996,12 +1009,14 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) return rc; } - rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC); + rsv = kmalloc(rsvsize, GFP_ATOMIC); if (!rsv) return -ENOMEM; - rsv->base = addr; - rsv->size = size; + rsv->size = 1; + atomic_set(&rsv->count, 1); + rsv->entry[0].base = addr; + rsv->entry[0].size = size; spin_lock(&efi_mem_reserve_persistent_lock); rsv->next = efi_memreserve_root->next; diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c index 3d36142cf812..9e20159ea5f5 100644 --- a/drivers/firmware/efi/libstub/arm-stub.c +++ b/drivers/firmware/efi/libstub/arm-stub.c @@ -86,8 +86,8 @@ void install_memreserve_table(efi_system_table_t *sys_table_arg) } rsv->next = 0; - rsv->base = 0; rsv->size = 0; + atomic_set(&rsv->count, 0); status = efi_call_early(install_configuration_table, &memreserve_table_guid, diff --git a/include/linux/efi.h b/include/linux/efi.h index 2b3b33c83b05..4f27640fdcdc 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1712,9 +1712,16 @@ extern struct efi_runtime_work efi_rts_work; extern struct workqueue_struct *efi_rts_wq; struct linux_efi_memreserve { - phys_addr_t next; - phys_addr_t base; - phys_addr_t size; + int size; // allocated size of the array + atomic_t count; // number of entries used + phys_addr_t next; // pa of next struct instance + struct { + phys_addr_t base; + phys_addr_t size; + } entry[0]; }; +#define EFI_MEMRESERVE_SIZE(count) (sizeof(struct linux_efi_memreserve) + \ + (count) * sizeof(((struct linux_efi_memreserve *)0)->entry[0])) + #endif /* _LINUX_EFI_H */
