aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/include/asm/code-patching.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2022-05-28 11:27:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-05-28 11:27:17 -0700
commit6112bd00e84e5dbffebc3c1e908cbe914ca772ee (patch)
tree06ffaf2e2e1623ad02d63ec615a03379ac833f3c /arch/powerpc/include/asm/code-patching.h
parentMerge tag 'pinctrl-v5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl (diff)
parentpowerpc/64: Include cache.h directly in paca.h (diff)
Merge tag 'powerpc-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman: - Convert to the generic mmap support (ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT) - Add support for outline-only KASAN with 64-bit Radix MMU (P9 or later) - Increase SIGSTKSZ and MINSIGSTKSZ and add support for AT_MINSIGSTKSZ - Enable the DAWR (Data Address Watchpoint) on POWER9 DD2.3 or later - Drop support for system call instruction emulation - Many other small features and fixes Thanks to Alexey Kardashevskiy, Alistair Popple, Andy Shevchenko, Bagas Sanjaya, Bjorn Helgaas, Bo Liu, Chen Huang, Christophe Leroy, Colin Ian King, Daniel Axtens, Dwaipayan Ray, Fabiano Rosas, Finn Thain, Frank Rowand, Fuqian Huang, Guilherme G. Piccoli, Hangyu Hua, Haowen Bai, Haren Myneni, Hari Bathini, He Ying, Jason Wang, Jiapeng Chong, Jing Yangyang, Joel Stanley, Julia Lawall, Kajol Jain, Kevin Hao, Krzysztof Kozlowski, Laurent Dufour, Lv Ruyi, Madhavan Srinivasan, Magali Lemes, Miaoqian Lin, Minghao Chi, Nathan Chancellor, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Oscar Salvador, Pali Rohár, Paul Mackerras, Peng Wu, Qing Wang, Randy Dunlap, Reza Arbab, Russell Currey, Sohaib Mohamed, Vaibhav Jain, Vasant Hegde, Wang Qing, Wang Wensheng, Xiang wangx, Xiaomeng Tong, Xu Wang, Yang Guang, Yang Li, Ye Bin, YueHaibing, Yu Kuai, Zheng Bin, Zou Wei, and Zucheng Zheng. * tag 'powerpc-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (200 commits) powerpc/64: Include cache.h directly in paca.h powerpc/64s: Only set HAVE_ARCH_UNMAPPED_AREA when CONFIG_PPC_64S_HASH_MMU is set powerpc/xics: Include missing header powerpc/powernv/pci: Drop VF MPS fixup powerpc/fsl_book3e: Don't set rodata RO too early powerpc/microwatt: Add mmu bits to device tree powerpc/powernv/flash: Check OPAL flash calls exist before using powerpc/powermac: constify device_node in of_irq_parse_oldworld() powerpc/powermac: add missing g5_phy_disable_cpu1() declaration selftests/powerpc/pmu: fix spelling mistake "mis-match" -> "mismatch" powerpc: Enable the DAWR on POWER9 DD2.3 and above powerpc/64s: Add CPU_FTRS_POWER10 to ALWAYS mask powerpc/64s: Add CPU_FTRS_POWER9_DD2_2 to CPU_FTRS_ALWAYS mask powerpc: Fix all occurences of "the the" selftests/powerpc/pmu/ebb: remove fixed_instruction.S powerpc/platforms/83xx: Use of_device_get_match_data() powerpc/eeh: Drop redundant spinlock initialization powerpc/iommu: Add missing of_node_put in iommu_init_early_dart powerpc/pseries/vas: Call misc_deregister if sysfs init fails powerpc/papr_scm: Fix leaking nvdimm_events_map elements ...
Diffstat (limited to 'arch/powerpc/include/asm/code-patching.h')
-rw-r--r--arch/powerpc/include/asm/code-patching.h67
1 files changed, 55 insertions, 12 deletions
diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h
index 409483b2d0ce..1c6316ec4b74 100644
--- a/arch/powerpc/include/asm/code-patching.h
+++ b/arch/powerpc/include/asm/code-patching.h
@@ -22,10 +22,55 @@
#define BRANCH_SET_LINK 0x1
#define BRANCH_ABSOLUTE 0x2
-bool is_offset_in_branch_range(long offset);
-bool is_offset_in_cond_branch_range(long offset);
-int create_branch(ppc_inst_t *instr, const u32 *addr,
- unsigned long target, int flags);
+DECLARE_STATIC_KEY_FALSE(init_mem_is_free);
+
+/*
+ * Powerpc branch instruction is :
+ *
+ * 0 6 30 31
+ * +---------+----------------+---+---+
+ * | opcode | LI |AA |LK |
+ * +---------+----------------+---+---+
+ * Where AA = 0 and LK = 0
+ *
+ * LI is a signed 24 bits integer. The real branch offset is computed
+ * by: imm32 = SignExtend(LI:'0b00', 32);
+ *
+ * So the maximum forward branch should be:
+ * (0x007fffff << 2) = 0x01fffffc = 0x1fffffc
+ * The maximum backward branch should be:
+ * (0xff800000 << 2) = 0xfe000000 = -0x2000000
+ */
+static inline bool is_offset_in_branch_range(long offset)
+{
+ return (offset >= -0x2000000 && offset <= 0x1fffffc && !(offset & 0x3));
+}
+
+static inline bool is_offset_in_cond_branch_range(long offset)
+{
+ return offset >= -0x8000 && offset <= 0x7fff && !(offset & 0x3);
+}
+
+static inline int create_branch(ppc_inst_t *instr, const u32 *addr,
+ unsigned long target, int flags)
+{
+ long offset;
+
+ *instr = ppc_inst(0);
+ offset = target;
+ if (! (flags & BRANCH_ABSOLUTE))
+ offset = offset - (unsigned long)addr;
+
+ /* Check we can represent the target in the instruction format */
+ if (!is_offset_in_branch_range(offset))
+ return 1;
+
+ /* Mask out the flags and target, so they don't step on each other. */
+ *instr = ppc_inst(0x48000000 | (flags & 0x3) | (offset & 0x03FFFFFC));
+
+ return 0;
+}
+
int create_cond_branch(ppc_inst_t *instr, const u32 *addr,
unsigned long target, int flags);
int patch_branch(u32 *addr, unsigned long target, int flags);
@@ -87,7 +132,7 @@ bool is_conditional_branch(ppc_inst_t instr);
static inline unsigned long ppc_function_entry(void *func)
{
-#ifdef PPC64_ELF_ABI_v2
+#ifdef CONFIG_PPC64_ELF_ABI_V2
u32 *insn = func;
/*
@@ -112,7 +157,7 @@ static inline unsigned long ppc_function_entry(void *func)
return (unsigned long)(insn + 2);
else
return (unsigned long)func;
-#elif defined(PPC64_ELF_ABI_v1)
+#elif defined(CONFIG_PPC64_ELF_ABI_V1)
/*
* On PPC64 ABIv1 the function pointer actually points to the
* function's descriptor. The first entry in the descriptor is the
@@ -126,7 +171,7 @@ static inline unsigned long ppc_function_entry(void *func)
static inline unsigned long ppc_global_function_entry(void *func)
{
-#ifdef PPC64_ELF_ABI_v2
+#ifdef CONFIG_PPC64_ELF_ABI_V2
/* PPC64 ABIv2 the global entry point is at the address */
return (unsigned long)func;
#else
@@ -143,7 +188,7 @@ static inline unsigned long ppc_global_function_entry(void *func)
static inline unsigned long ppc_kallsyms_lookup_name(const char *name)
{
unsigned long addr;
-#ifdef PPC64_ELF_ABI_v1
+#ifdef CONFIG_PPC64_ELF_ABI_V1
/* check for dot variant */
char dot_name[1 + KSYM_NAME_LEN];
bool dot_appended = false;
@@ -164,7 +209,7 @@ static inline unsigned long ppc_kallsyms_lookup_name(const char *name)
if (!addr && dot_appended)
/* Let's try the original non-dot symbol lookup */
addr = kallsyms_lookup_name(name);
-#elif defined(PPC64_ELF_ABI_v2)
+#elif defined(CONFIG_PPC64_ELF_ABI_V2)
addr = kallsyms_lookup_name(name);
if (addr)
addr = ppc_function_entry((void *)addr);
@@ -174,14 +219,13 @@ static inline unsigned long ppc_kallsyms_lookup_name(const char *name)
return addr;
}
-#ifdef CONFIG_PPC64
/*
* Some instruction encodings commonly used in dynamic ftracing
* and function live patching.
*/
/* This must match the definition of STK_GOT in <asm/ppc_asm.h> */
-#ifdef PPC64_ELF_ABI_v2
+#ifdef CONFIG_PPC64_ELF_ABI_V2
#define R2_STACK_OFFSET 24
#else
#define R2_STACK_OFFSET 40
@@ -191,6 +235,5 @@ static inline unsigned long ppc_kallsyms_lookup_name(const char *name)
/* usually preceded by a mflr r0 */
#define PPC_INST_STD_LR PPC_RAW_STD(_R0, _R1, PPC_LR_STKOFF)
-#endif /* CONFIG_PPC64 */
#endif /* _ASM_POWERPC_CODE_PATCHING_H */