#include <asm/mmu.h>
/*
- * We only have to have statically allocated lppaca structs on
- * legacy iSeries, which supports at most 64 cpus.
- */
-#define NR_LPPACAS 1
-
-/*
- * The Hypervisor barfs if the lppaca crosses a page boundary. A 1k
- * alignment is sufficient to prevent this
+ * The lppaca is the "virtual processor area" registered with the hypervisor,
+ * H_REGISTER_VPA etc.
+ *
+ * According to PAPR, the structure is 640 bytes long, must be L1 cache line
+ * aligned, and must not cross a 4kB boundary. Its size field must be at
+ * least 640 bytes (but may be more).
+ *
+ * Pre-v4.14 KVM hypervisors reject the VPA if its size field is smaller than
+ * 1kB, so we dynamically allocate 1kB and advertise size as 1kB, but keep
+ * this structure as the canonical 640 byte size.
*/
struct lppaca {
/* cacheline 1 contains read-only data */
__be32 page_ins; /* CMO Hint - # page ins by OS */
u8 reserved11[148];
- volatile __be64 dtl_idx; /* Dispatch Trace Log head index */
+ volatile __be64 dtl_idx; /* Dispatch Trace Log head index */
u8 reserved12[96];
-} __attribute__((__aligned__(0x400)));
-
-extern struct lppaca lppaca[];
+} ____cacheline_aligned;
#define lppaca_of(cpu) (*paca_ptrs[cpu]->lppaca_ptr)
kexec_stack.thread_info.cpu = current_thread_info()->cpu;
/* We need a static PACA, too; copy this CPU's PACA over and switch to
- * it. Also poison per_cpu_offset to catch anyone using non-static
- * data.
+ * it. Also poison per_cpu_offset and NULL lppaca to catch anyone using
+ * non-static data.
*/
memcpy(&kexec_paca, get_paca(), sizeof(struct paca_struct));
kexec_paca.data_offset = 0xedeaddeadeeeeeeeUL;
+#ifdef CONFIG_PPC_PSERIES
+ kexec_paca.lppaca_ptr = NULL;
+#endif
paca_ptrs[kexec_paca.paca_index] = &kexec_paca;
+
setup_paca(&kexec_paca);
- /* XXX: If anyone does 'dynamic lppacas' this will also need to be
- * switched to a static version!
+ /*
+ * The lppaca should be unregistered at this point so the HV won't
+ * touch it. In the case of a crash, none of the lppacas are
+ * unregistered so there is not much we can do about it here.
*/
+
/*
* On Book3S, the copy must happen with the MMU off if we are either
* using Radix page tables or we are not in an LPAR since we can
#ifdef CONFIG_PPC_PSERIES
/*
- * The structure which the hypervisor knows about - this structure
- * should not cross a page boundary. The vpa_init/register_vpa call
- * is now known to fail if the lppaca structure crosses a page
- * boundary. The lppaca is also used on POWER5 pSeries boxes.
- * The lppaca is 640 bytes long, and cannot readily
- * change since the hypervisor knows its layout, so a 1kB alignment
- * will suffice to ensure that it doesn't cross a page boundary.
+ * See asm/lppaca.h for more detail.
+ *
+ * lppaca structures must must be 1kB in size, L1 cache line aligned,
+ * and not cross 4kB boundary. A 1kB size and 1kB alignment will satisfy
+ * these requirements.
*/
-struct lppaca lppaca[] = {
- [0 ... (NR_LPPACAS-1)] = {
+static inline void init_lppaca(struct lppaca *lppaca)
+{
+ BUILD_BUG_ON(sizeof(struct lppaca) != 640);
+
+ *lppaca = (struct lppaca) {
.desc = cpu_to_be32(0xd397d781), /* "LpPa" */
- .size = cpu_to_be16(sizeof(struct lppaca)),
+ .size = cpu_to_be16(0x400),
.fpregs_in_use = 1,
.slb_count = cpu_to_be16(64),
.vmxregs_in_use = 0,
- .page_ins = 0,
- },
+ .page_ins = 0, };
};
-static struct lppaca *extra_lppacas;
-static long __initdata lppaca_size;
-
-static void __init allocate_lppacas(int nr_cpus, unsigned long limit)
-{
- if (early_cpu_has_feature(CPU_FTR_HVMODE))
- return;
-
- if (nr_cpus <= NR_LPPACAS)
- return;
-
- lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) *
- (nr_cpus - NR_LPPACAS));
- extra_lppacas = __va(memblock_alloc_base(lppaca_size,
- PAGE_SIZE, limit));
-}
-
-static struct lppaca * __init new_lppaca(int cpu)
+static struct lppaca * __init new_lppaca(int cpu, unsigned long limit)
{
struct lppaca *lp;
+ size_t size = 0x400;
+
+ BUILD_BUG_ON(size < sizeof(struct lppaca));
if (early_cpu_has_feature(CPU_FTR_HVMODE))
return NULL;
- if (cpu < NR_LPPACAS)
- return &lppaca[cpu];
-
- lp = extra_lppacas + (cpu - NR_LPPACAS);
- *lp = lppaca[0];
+ lp = __va(memblock_alloc_base(size, 0x400, limit));
+ init_lppaca(lp);
return lp;
}
-static void __init free_lppacas(void)
+static void __init free_lppaca(struct lppaca *lp)
{
- long new_size = 0, nr;
+ size_t size = 0x400;
if (early_cpu_has_feature(CPU_FTR_HVMODE))
return;
- if (!lppaca_size)
- return;
- nr = num_possible_cpus() - NR_LPPACAS;
- if (nr > 0)
- new_size = PAGE_ALIGN(nr * sizeof(struct lppaca));
- if (new_size >= lppaca_size)
- return;
-
- memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size);
- lppaca_size = new_size;
+ memblock_free(__pa(lp), size);
}
-
-#else
-
-static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { }
-static inline void free_lppacas(void) { }
-
#endif /* CONFIG_PPC_BOOK3S */
#ifdef CONFIG_PPC_BOOK3S_64
void __init initialise_paca(struct paca_struct *new_paca, int cpu)
{
#ifdef CONFIG_PPC_PSERIES
- new_paca->lppaca_ptr = new_lppaca(cpu);
+ new_paca->lppaca_ptr = NULL;
#endif
#ifdef CONFIG_PPC_BOOK3E
new_paca->kernel_pgd = swapper_pg_dir;
printk(KERN_DEBUG "Allocated %lu bytes for %u pacas\n",
size, nr_cpu_ids);
- allocate_lppacas(nr_cpu_ids, limit);
-
allocate_slb_shadows(nr_cpu_ids, limit);
/* Can't use for_each_*_cpu, as they aren't functional yet */
- for (cpu = 0; cpu < nr_cpu_ids; cpu++)
+ for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
initialise_paca(paca_ptrs[cpu], cpu);
+#ifdef CONFIG_PPC_PSERIES
+ paca_ptrs[cpu]->lppaca_ptr = new_lppaca(cpu, limit);
+#endif
+ }
}
void __init free_unused_pacas(void)
for (cpu = 0; cpu < paca_nr_cpu_ids; cpu++) {
if (!cpu_possible(cpu)) {
unsigned long pa = __pa(paca_ptrs[cpu]);
+#ifdef CONFIG_PPC_PSERIES
+ free_lppaca(paca_ptrs[cpu]->lppaca_ptr);
+#endif
memblock_free(pa, sizeof(struct paca_struct));
paca_ptrs[cpu] = NULL;
size += sizeof(struct paca_struct);
if (size)
printk(KERN_DEBUG "Freed %lu bytes for unused pacas\n", size);
- free_lppacas();
-
paca_nr_cpu_ids = nr_cpu_ids;
paca_ptrs_size = new_ptrs_size;
}
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