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-rw-r--r--arch/s390/kernel/asm-offsets.c1
-rw-r--r--arch/s390/kernel/cert_store.c2
-rw-r--r--arch/s390/kernel/cpufeature.c5
-rw-r--r--arch/s390/kernel/crash_dump.c2
-rw-r--r--arch/s390/kernel/debug.c2
-rw-r--r--arch/s390/kernel/entry.S23
-rw-r--r--arch/s390/kernel/ipl.c27
-rw-r--r--arch/s390/kernel/perf_cpum_cf.c2
-rw-r--r--arch/s390/kernel/perf_cpum_cf_events.c4
-rw-r--r--arch/s390/kernel/perf_cpum_sf.c5
-rw-r--r--arch/s390/kernel/processor.c16
-rw-r--r--arch/s390/kernel/ptrace.c33
-rw-r--r--arch/s390/kernel/smp.c2
-rw-r--r--arch/s390/kernel/uv.c144
14 files changed, 130 insertions, 138 deletions
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index 841e05f7fa7e..95ecad9c7d7d 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -50,7 +50,6 @@ int main(void)
OFFSET(__PT_ORIG_GPR2, pt_regs, orig_gpr2);
OFFSET(__PT_INT_CODE, pt_regs, int_code);
OFFSET(__PT_FLAGS, pt_regs, flags);
- OFFSET(__PT_CR1, pt_regs, cr1);
OFFSET(__PT_LAST_BREAK, pt_regs, last_break);
DEFINE(__PT_SIZE, sizeof(struct pt_regs));
BLANK();
diff --git a/arch/s390/kernel/cert_store.c b/arch/s390/kernel/cert_store.c
index 03f3a1e52430..c217a5e64094 100644
--- a/arch/s390/kernel/cert_store.c
+++ b/arch/s390/kernel/cert_store.c
@@ -138,7 +138,7 @@ static void cert_store_key_describe(const struct key *key, struct seq_file *m)
* First 64 bytes of the key description is key name in EBCDIC CP 500.
* Convert it to ASCII for displaying in /proc/keys.
*/
- strscpy(ascii, key->description, sizeof(ascii));
+ strscpy(ascii, key->description);
EBCASC_500(ascii, VC_NAME_LEN_BYTES);
seq_puts(m, ascii);
diff --git a/arch/s390/kernel/cpufeature.c b/arch/s390/kernel/cpufeature.c
index 1b2ae42a0c15..76210f001028 100644
--- a/arch/s390/kernel/cpufeature.c
+++ b/arch/s390/kernel/cpufeature.c
@@ -5,11 +5,13 @@
#include <linux/cpufeature.h>
#include <linux/bug.h>
+#include <asm/machine.h>
#include <asm/elf.h>
enum {
TYPE_HWCAP,
TYPE_FACILITY,
+ TYPE_MACHINE,
};
struct s390_cpu_feature {
@@ -21,6 +23,7 @@ static struct s390_cpu_feature s390_cpu_features[MAX_CPU_FEATURES] = {
[S390_CPU_FEATURE_MSA] = {.type = TYPE_HWCAP, .num = HWCAP_NR_MSA},
[S390_CPU_FEATURE_VXRS] = {.type = TYPE_HWCAP, .num = HWCAP_NR_VXRS},
[S390_CPU_FEATURE_UV] = {.type = TYPE_FACILITY, .num = 158},
+ [S390_CPU_FEATURE_D288] = {.type = TYPE_MACHINE, .num = MFEATURE_DIAG288},
};
/*
@@ -38,6 +41,8 @@ int cpu_have_feature(unsigned int num)
return !!(elf_hwcap & BIT(feature->num));
case TYPE_FACILITY:
return test_facility(feature->num);
+ case TYPE_MACHINE:
+ return test_machine_feature(feature->num);
default:
WARN_ON_ONCE(1);
return 0;
diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index 4a981266b483..adb164223f8c 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -354,7 +354,7 @@ static void *nt_prpsinfo(void *ptr)
memset(&prpsinfo, 0, sizeof(prpsinfo));
prpsinfo.pr_sname = 'R';
- strcpy(prpsinfo.pr_fname, "vmlinux");
+ strscpy(prpsinfo.pr_fname, "vmlinux");
return nt_init(ptr, PRPSINFO, prpsinfo);
}
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
index ce038e9205f7..2a41be2f7925 100644
--- a/arch/s390/kernel/debug.c
+++ b/arch/s390/kernel/debug.c
@@ -251,7 +251,7 @@ static debug_info_t *debug_info_alloc(const char *name, int pages_per_area,
rc->level = level;
rc->buf_size = buf_size;
rc->entry_size = sizeof(debug_entry_t) + buf_size;
- strscpy(rc->name, name, sizeof(rc->name));
+ strscpy(rc->name, name);
memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
memset(rc->debugfs_entries, 0, DEBUG_MAX_VIEWS * sizeof(struct dentry *));
refcount_set(&(rc->ref_count), 0);
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index dd291c9ad6a6..0f00f4b06d51 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -116,7 +116,7 @@ _LPP_OFFSET = __LC_LPP
.macro SIEEXIT sie_control,lowcore
lg %r9,\sie_control # get control block pointer
ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE
- lctlg %c1,%c1,__LC_KERNEL_ASCE(\lowcore) # load primary asce
+ lctlg %c1,%c1,__LC_USER_ASCE(\lowcore) # load primary asce
lg %r9,__LC_CURRENT(\lowcore)
mvi __TI_sie(%r9),0
larl %r9,sie_exit # skip forward to sie_exit
@@ -208,7 +208,7 @@ SYM_FUNC_START(__sie64a)
lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer
ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
GET_LC %r14
- lctlg %c1,%c1,__LC_KERNEL_ASCE(%r14) # load primary asce
+ lctlg %c1,%c1,__LC_USER_ASCE(%r14) # load primary asce
lg %r14,__LC_CURRENT(%r14)
mvi __TI_sie(%r14),0
SYM_INNER_LABEL(sie_exit, SYM_L_GLOBAL)
@@ -240,7 +240,6 @@ SYM_CODE_START(system_call)
lghi %r14,0
.Lsysc_per:
STBEAR __LC_LAST_BREAK(%r13)
- lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13)
lg %r15,__LC_KERNEL_STACK(%r13)
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
stmg %r0,%r7,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
@@ -261,7 +260,6 @@ SYM_CODE_START(system_call)
lgr %r3,%r14
brasl %r14,__do_syscall
STACKLEAK_ERASE
- lctlg %c1,%c1,__LC_USER_ASCE(%r13)
mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)
BPON
LBEAR STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15)
@@ -278,7 +276,6 @@ SYM_CODE_START(ret_from_fork)
brasl %r14,__ret_from_fork
STACKLEAK_ERASE
GET_LC %r13
- lctlg %c1,%c1,__LC_USER_ASCE(%r13)
mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)
BPON
LBEAR STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15)
@@ -299,10 +296,7 @@ SYM_CODE_START(pgm_check_handler)
lmg %r8,%r9,__LC_PGM_OLD_PSW(%r13)
xgr %r10,%r10
tmhh %r8,0x0001 # coming from user space?
- jno .Lpgm_skip_asce
- lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13)
- j 3f # -> fault in user space
-.Lpgm_skip_asce:
+ jo 3f # -> fault in user space
#if IS_ENABLED(CONFIG_KVM)
lg %r11,__LC_CURRENT(%r13)
tm __TI_sie(%r11),0xff
@@ -340,7 +334,6 @@ SYM_CODE_START(pgm_check_handler)
tmhh %r8,0x0001 # returning to user space?
jno .Lpgm_exit_kernel
STACKLEAK_ERASE
- lctlg %c1,%c1,__LC_USER_ASCE(%r13)
BPON
stpt __LC_EXIT_TIMER(%r13)
.Lpgm_exit_kernel:
@@ -384,8 +377,7 @@ SYM_CODE_START(\name)
#endif
0: aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
j 2f
-1: lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13)
- lg %r15,__LC_KERNEL_STACK(%r13)
+1: lg %r15,__LC_KERNEL_STACK(%r13)
2: xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
la %r11,STACK_FRAME_OVERHEAD(%r15)
stmg %r0,%r7,__PT_R0(%r11)
@@ -408,7 +400,6 @@ SYM_CODE_START(\name)
tmhh %r8,0x0001 # returning to user ?
jno 2f
STACKLEAK_ERASE
- lctlg %c1,%c1,__LC_USER_ASCE(%r13)
BPON
stpt __LC_EXIT_TIMER(%r13)
2: LBEAR __PT_LAST_BREAK(%r11)
@@ -476,8 +467,6 @@ SYM_CODE_START(mcck_int_handler)
.Lmcck_user:
lg %r15,__LC_MCCK_STACK(%r13)
la %r11,STACK_FRAME_OVERHEAD(%r15)
- stctg %c1,%c1,__PT_CR1(%r11)
- lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13)
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
lay %r14,__LC_GPREGS_SAVE_AREA(%r13)
mvc __PT_R0(128,%r11),0(%r14)
@@ -495,7 +484,6 @@ SYM_CODE_START(mcck_int_handler)
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
lgr %r2,%r11 # pass pointer to pt_regs
brasl %r14,s390_do_machine_check
- lctlg %c1,%c1,__PT_CR1(%r11)
lmg %r0,%r10,__PT_R0(%r11)
mvc __LC_RETURN_MCCK_PSW(16,%r13),__PT_PSW(%r11) # move return PSW
tm __LC_RETURN_MCCK_PSW+1(%r13),0x01 # returning to user ?
@@ -602,7 +590,8 @@ SYM_CODE_START(stack_invalid)
stmg %r0,%r7,__PT_R0(%r11)
stmg %r8,%r9,__PT_PSW(%r11)
mvc __PT_R8(64,%r11),0(%r14)
- stg %r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
+ GET_LC %r2
+ mvc __PT_ORIG_GPR2(8,%r11),__LC_PGM_LAST_BREAK(%r2)
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
lgr %r2,%r11 # pass pointer to pt_regs
jg kernel_stack_invalid
diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index 3b9d9ccfad63..ff15f91affde 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -270,7 +270,7 @@ static ssize_t sys_##_prefix##_##_name##_store(struct kobject *kobj, \
{ \
if (len >= sizeof(_value)) \
return -E2BIG; \
- len = strscpy(_value, buf, sizeof(_value)); \
+ len = strscpy(_value, buf); \
if ((ssize_t)len < 0) \
return len; \
strim(_value); \
@@ -2249,26 +2249,28 @@ static int __init s390_ipl_init(void)
__initcall(s390_ipl_init);
-static void __init strncpy_skip_quote(char *dst, char *src, int n)
+static void __init strscpy_skip_quote(char *dst, char *src, int n)
{
int sx, dx;
- dx = 0;
- for (sx = 0; src[sx] != 0; sx++) {
+ if (!n)
+ return;
+ for (sx = 0, dx = 0; src[sx]; sx++) {
if (src[sx] == '"')
continue;
- dst[dx++] = src[sx];
- if (dx >= n)
+ dst[dx] = src[sx];
+ if (dx + 1 == n)
break;
+ dx++;
}
+ dst[dx] = '\0';
}
static int __init vmcmd_on_reboot_setup(char *str)
{
if (!machine_is_vm())
return 1;
- strncpy_skip_quote(vmcmd_on_reboot, str, VMCMD_MAX_SIZE);
- vmcmd_on_reboot[VMCMD_MAX_SIZE] = 0;
+ strscpy_skip_quote(vmcmd_on_reboot, str, sizeof(vmcmd_on_reboot));
on_reboot_trigger.action = &vmcmd_action;
return 1;
}
@@ -2278,8 +2280,7 @@ static int __init vmcmd_on_panic_setup(char *str)
{
if (!machine_is_vm())
return 1;
- strncpy_skip_quote(vmcmd_on_panic, str, VMCMD_MAX_SIZE);
- vmcmd_on_panic[VMCMD_MAX_SIZE] = 0;
+ strscpy_skip_quote(vmcmd_on_panic, str, sizeof(vmcmd_on_panic));
on_panic_trigger.action = &vmcmd_action;
return 1;
}
@@ -2289,8 +2290,7 @@ static int __init vmcmd_on_halt_setup(char *str)
{
if (!machine_is_vm())
return 1;
- strncpy_skip_quote(vmcmd_on_halt, str, VMCMD_MAX_SIZE);
- vmcmd_on_halt[VMCMD_MAX_SIZE] = 0;
+ strscpy_skip_quote(vmcmd_on_halt, str, sizeof(vmcmd_on_halt));
on_halt_trigger.action = &vmcmd_action;
return 1;
}
@@ -2300,8 +2300,7 @@ static int __init vmcmd_on_poff_setup(char *str)
{
if (!machine_is_vm())
return 1;
- strncpy_skip_quote(vmcmd_on_poff, str, VMCMD_MAX_SIZE);
- vmcmd_on_poff[VMCMD_MAX_SIZE] = 0;
+ strscpy_skip_quote(vmcmd_on_poff, str, sizeof(vmcmd_on_poff));
on_poff_trigger.action = &vmcmd_action;
return 1;
}
diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c
index e657fad7e376..6a262e198e35 100644
--- a/arch/s390/kernel/perf_cpum_cf.c
+++ b/arch/s390/kernel/perf_cpum_cf.c
@@ -980,8 +980,6 @@ static int cfdiag_push_sample(struct perf_event *event,
}
overflow = perf_event_overflow(event, &data, &regs);
- if (overflow)
- event->pmu->stop(event, 0);
perf_event_update_userpage(event);
return overflow;
diff --git a/arch/s390/kernel/perf_cpum_cf_events.c b/arch/s390/kernel/perf_cpum_cf_events.c
index 690a293eb10d..7ace1f9e4ccf 100644
--- a/arch/s390/kernel/perf_cpum_cf_events.c
+++ b/arch/s390/kernel/perf_cpum_cf_events.c
@@ -290,8 +290,8 @@ CPUMF_EVENT_ATTR(cf_z15, TX_C_TABORT_NO_SPECIAL, 0x00f4);
CPUMF_EVENT_ATTR(cf_z15, TX_C_TABORT_SPECIAL, 0x00f5);
CPUMF_EVENT_ATTR(cf_z15, DFLT_ACCESS, 0x00f7);
CPUMF_EVENT_ATTR(cf_z15, DFLT_CYCLES, 0x00fc);
-CPUMF_EVENT_ATTR(cf_z15, DFLT_CC, 0x00108);
-CPUMF_EVENT_ATTR(cf_z15, DFLT_CCFINISH, 0x00109);
+CPUMF_EVENT_ATTR(cf_z15, DFLT_CC, 0x0108);
+CPUMF_EVENT_ATTR(cf_z15, DFLT_CCFINISH, 0x0109);
CPUMF_EVENT_ATTR(cf_z15, MT_DIAG_CYCLES_ONE_THR_ACTIVE, 0x01c0);
CPUMF_EVENT_ATTR(cf_z15, MT_DIAG_CYCLES_TWO_THR_ACTIVE, 0x01c1);
CPUMF_EVENT_ATTR(cf_z16, L1D_RO_EXCL_WRITES, 0x0080);
diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c
index ad22799d8a7d..91469401f2c9 100644
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -1072,10 +1072,7 @@ static int perf_push_sample(struct perf_event *event,
overflow = 0;
if (perf_event_exclude(event, &regs, sde_regs))
goto out;
- if (perf_event_overflow(event, &data, &regs)) {
- overflow = 1;
- event->pmu->stop(event, 0);
- }
+ overflow = perf_event_overflow(event, &data, &regs);
perf_event_update_userpage(event);
out:
return overflow;
diff --git a/arch/s390/kernel/processor.c b/arch/s390/kernel/processor.c
index 80b1f7a29f11..11f70c1e2797 100644
--- a/arch/s390/kernel/processor.c
+++ b/arch/s390/kernel/processor.c
@@ -268,35 +268,35 @@ static int __init setup_elf_platform(void)
add_device_randomness(&cpu_id, sizeof(cpu_id));
switch (cpu_id.machine) {
default: /* Use "z10" as default. */
- strcpy(elf_platform, "z10");
+ strscpy(elf_platform, "z10");
break;
case 0x2817:
case 0x2818:
- strcpy(elf_platform, "z196");
+ strscpy(elf_platform, "z196");
break;
case 0x2827:
case 0x2828:
- strcpy(elf_platform, "zEC12");
+ strscpy(elf_platform, "zEC12");
break;
case 0x2964:
case 0x2965:
- strcpy(elf_platform, "z13");
+ strscpy(elf_platform, "z13");
break;
case 0x3906:
case 0x3907:
- strcpy(elf_platform, "z14");
+ strscpy(elf_platform, "z14");
break;
case 0x8561:
case 0x8562:
- strcpy(elf_platform, "z15");
+ strscpy(elf_platform, "z15");
break;
case 0x3931:
case 0x3932:
- strcpy(elf_platform, "z16");
+ strscpy(elf_platform, "z16");
break;
case 0x9175:
case 0x9176:
- strcpy(elf_platform, "z17");
+ strscpy(elf_platform, "z17");
break;
}
return 0;
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 34b8d9e745df..e1240f6b29fa 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -1524,13 +1524,6 @@ static const char *gpr_names[NUM_GPRS] = {
"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
};
-unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
-{
- if (offset >= NUM_GPRS)
- return 0;
- return regs->gprs[offset];
-}
-
int regs_query_register_offset(const char *name)
{
unsigned long offset;
@@ -1550,29 +1543,3 @@ const char *regs_query_register_name(unsigned int offset)
return NULL;
return gpr_names[offset];
}
-
-static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
-{
- unsigned long ksp = kernel_stack_pointer(regs);
-
- return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
-}
-
-/**
- * regs_get_kernel_stack_nth() - get Nth entry of the stack
- * @regs:pt_regs which contains kernel stack pointer.
- * @n:stack entry number.
- *
- * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
- * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
- * this returns 0.
- */
-unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
-{
- unsigned long addr;
-
- addr = kernel_stack_pointer(regs) + n * sizeof(long);
- if (!regs_within_kernel_stack(regs, addr))
- return 0;
- return READ_ONCE_NOCHECK(addr);
-}
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 63f41dfaba85..81f12bb77f62 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -263,7 +263,7 @@ static void pcpu_prepare_secondary(struct pcpu *pcpu, int cpu)
abs_lc = get_abs_lowcore();
memcpy(lc->cregs_save_area, abs_lc->cregs_save_area, sizeof(lc->cregs_save_area));
put_abs_lowcore(abs_lc);
- lc->cregs_save_area[1] = lc->kernel_asce;
+ lc->cregs_save_area[1] = lc->user_asce;
lc->cregs_save_area[7] = lc->user_asce;
save_access_regs((unsigned int *) lc->access_regs_save_area);
arch_spin_lock_setup(cpu);
diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c
index 9a5d5be8acf4..b99478e84da4 100644
--- a/arch/s390/kernel/uv.c
+++ b/arch/s390/kernel/uv.c
@@ -15,6 +15,7 @@
#include <linux/pagemap.h>
#include <linux/swap.h>
#include <linux/pagewalk.h>
+#include <linux/backing-dev.h>
#include <asm/facility.h>
#include <asm/sections.h>
#include <asm/uv.h>
@@ -135,7 +136,7 @@ int uv_destroy_folio(struct folio *folio)
{
int rc;
- /* See gmap_make_secure(): large folios cannot be secure */
+ /* Large folios cannot be secure */
if (unlikely(folio_test_large(folio)))
return 0;
@@ -184,7 +185,7 @@ int uv_convert_from_secure_folio(struct folio *folio)
{
int rc;
- /* See gmap_make_secure(): large folios cannot be secure */
+ /* Large folios cannot be secure */
if (unlikely(folio_test_large(folio)))
return 0;
@@ -324,32 +325,87 @@ static int make_folio_secure(struct mm_struct *mm, struct folio *folio, struct u
}
/**
- * s390_wiggle_split_folio() - try to drain extra references to a folio and optionally split.
+ * s390_wiggle_split_folio() - try to drain extra references to a folio and
+ * split the folio if it is large.
* @mm: the mm containing the folio to work on
* @folio: the folio
- * @split: whether to split a large folio
*
* Context: Must be called while holding an extra reference to the folio;
* the mm lock should not be held.
- * Return: 0 if the folio was split successfully;
- * -EAGAIN if the folio was not split successfully but another attempt
- * can be made, or if @split was set to false;
- * -EINVAL in case of other errors. See split_folio().
+ * Return: 0 if the operation was successful;
+ * -EAGAIN if splitting the large folio was not successful,
+ * but another attempt can be made;
+ * -EINVAL in case of other folio splitting errors. See split_folio().
*/
-static int s390_wiggle_split_folio(struct mm_struct *mm, struct folio *folio, bool split)
+static int s390_wiggle_split_folio(struct mm_struct *mm, struct folio *folio)
{
- int rc;
+ int rc, tried_splits;
lockdep_assert_not_held(&mm->mmap_lock);
folio_wait_writeback(folio);
lru_add_drain_all();
- if (split) {
+
+ if (!folio_test_large(folio))
+ return 0;
+
+ for (tried_splits = 0; tried_splits < 2; tried_splits++) {
+ struct address_space *mapping;
+ loff_t lstart, lend;
+ struct inode *inode;
+
folio_lock(folio);
rc = split_folio(folio);
+ if (rc != -EBUSY) {
+ folio_unlock(folio);
+ return rc;
+ }
+
+ /*
+ * Splitting with -EBUSY can fail for various reasons, but we
+ * have to handle one case explicitly for now: some mappings
+ * don't allow for splitting dirty folios; writeback will
+ * mark them clean again, including marking all page table
+ * entries mapping the folio read-only, to catch future write
+ * attempts.
+ *
+ * While the system should be writing back dirty folios in the
+ * background, we obtained this folio by looking up a writable
+ * page table entry. On these problematic mappings, writable
+ * page table entries imply dirty folios, preventing the
+ * split in the first place.
+ *
+ * To prevent a livelock when trigger writeback manually and
+ * letting the caller look up the folio again in the page
+ * table (turning it dirty), immediately try to split again.
+ *
+ * This is only a problem for some mappings (e.g., XFS);
+ * mappings that do not support writeback (e.g., shmem) do not
+ * apply.
+ */
+ if (!folio_test_dirty(folio) || folio_test_anon(folio) ||
+ !folio->mapping || !mapping_can_writeback(folio->mapping)) {
+ folio_unlock(folio);
+ break;
+ }
+
+ /*
+ * Ideally, we'd only trigger writeback on this exact folio. But
+ * there is no easy way to do that, so we'll stabilize the
+ * mapping while we still hold the folio lock, so we can drop
+ * the folio lock to trigger writeback on the range currently
+ * covered by the folio instead.
+ */
+ mapping = folio->mapping;
+ lstart = folio_pos(folio);
+ lend = lstart + folio_size(folio) - 1;
+ inode = igrab(mapping->host);
folio_unlock(folio);
- if (rc != -EBUSY)
- return rc;
+ if (unlikely(!inode))
+ break;
+
+ filemap_write_and_wait_range(mapping, lstart, lend);
+ iput(mapping->host);
}
return -EAGAIN;
}
@@ -393,8 +449,11 @@ int make_hva_secure(struct mm_struct *mm, unsigned long hva, struct uv_cb_header
folio_walk_end(&fw, vma);
mmap_read_unlock(mm);
- if (rc == -E2BIG || rc == -EBUSY)
- rc = s390_wiggle_split_folio(mm, folio, rc == -E2BIG);
+ if (rc == -E2BIG || rc == -EBUSY) {
+ rc = s390_wiggle_split_folio(mm, folio);
+ if (!rc)
+ rc = -EAGAIN;
+ }
folio_put(folio);
return rc;
@@ -403,15 +462,15 @@ EXPORT_SYMBOL_GPL(make_hva_secure);
/*
* To be called with the folio locked or with an extra reference! This will
- * prevent gmap_make_secure from touching the folio concurrently. Having 2
- * parallel arch_make_folio_accessible is fine, as the UV calls will become a
- * no-op if the folio is already exported.
+ * prevent kvm_s390_pv_make_secure() from touching the folio concurrently.
+ * Having 2 parallel arch_make_folio_accessible is fine, as the UV calls will
+ * become a no-op if the folio is already exported.
*/
int arch_make_folio_accessible(struct folio *folio)
{
int rc = 0;
- /* See gmap_make_secure(): large folios cannot be secure */
+ /* Large folios cannot be secure */
if (unlikely(folio_test_large(folio)))
return 0;
@@ -782,7 +841,12 @@ out_kobj:
device_initcall(uv_sysfs_init);
/*
- * Find the secret with the secret_id in the provided list.
+ * Locate a secret in the list by its id.
+ * @secret_id: search pattern.
+ * @list: ephemeral buffer space
+ * @secret: output data, containing the secret's metadata.
+ *
+ * Search for a secret with the given secret_id in the Ultravisor secret store.
*
* Context: might sleep.
*/
@@ -803,12 +867,15 @@ static int find_secret_in_page(const u8 secret_id[UV_SECRET_ID_LEN],
/*
* Do the actual search for `uv_get_secret_metadata`.
+ * @secret_id: search pattern.
+ * @list: ephemeral buffer space
+ * @secret: output data, containing the secret's metadata.
*
* Context: might sleep.
*/
-static int find_secret(const u8 secret_id[UV_SECRET_ID_LEN],
- struct uv_secret_list *list,
- struct uv_secret_list_item_hdr *secret)
+int uv_find_secret(const u8 secret_id[UV_SECRET_ID_LEN],
+ struct uv_secret_list *list,
+ struct uv_secret_list_item_hdr *secret)
{
u16 start_idx = 0;
u16 list_rc;
@@ -830,36 +897,7 @@ static int find_secret(const u8 secret_id[UV_SECRET_ID_LEN],
return -ENOENT;
}
-
-/**
- * uv_get_secret_metadata() - get secret metadata for a given secret id.
- * @secret_id: search pattern.
- * @secret: output data, containing the secret's metadata.
- *
- * Search for a secret with the given secret_id in the Ultravisor secret store.
- *
- * Context: might sleep.
- *
- * Return:
- * * %0: - Found entry; secret->idx and secret->type are valid.
- * * %ENOENT - No entry found.
- * * %ENODEV: - Not supported: UV not available or command not available.
- * * %EIO: - Other unexpected UV error.
- */
-int uv_get_secret_metadata(const u8 secret_id[UV_SECRET_ID_LEN],
- struct uv_secret_list_item_hdr *secret)
-{
- struct uv_secret_list *buf;
- int rc;
-
- buf = kzalloc(sizeof(*buf), GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
- rc = find_secret(secret_id, buf, secret);
- kfree(buf);
- return rc;
-}
-EXPORT_SYMBOL_GPL(uv_get_secret_metadata);
+EXPORT_SYMBOL_GPL(uv_find_secret);
/**
* uv_retrieve_secret() - get the secret value for the secret index.
generated by cgit (git 2.34.1) at 2025-06-03 16:40:22 +0000