From 382ac6b3fbc0ea6a5697fc6caaf7e7de12fa8b96 Mon Sep 17 00:00:00 2001 From: Glauber de Oliveira Costa Date: Thu, 17 Jan 2008 19:19:42 -0200 Subject: [PATCH] lguest: get rid of lg variable assignments We can save some lines of code by getting rid of *lg = cpu... lines of code spread everywhere by now. Signed-off-by: Glauber de Oliveira Costa Signed-off-by: Rusty Russell --- drivers/lguest/core.c | 24 +++--- drivers/lguest/hypercalls.c | 49 ++++++----- drivers/lguest/interrupts_and_traps.c | 54 ++++++------ drivers/lguest/lg.h | 28 +++---- drivers/lguest/page_tables.c | 115 +++++++++++++------------- drivers/lguest/segments.c | 8 +- drivers/lguest/x86/core.c | 30 ++++--- 7 files changed, 149 insertions(+), 159 deletions(-) diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c index 6023872e32..7743d73768 100644 --- a/drivers/lguest/core.c +++ b/drivers/lguest/core.c @@ -151,23 +151,23 @@ int lguest_address_ok(const struct lguest *lg, /* This routine copies memory from the Guest. Here we can see how useful the * kill_lguest() routine we met in the Launcher can be: we return a random * value (all zeroes) instead of needing to return an error. */ -void __lgread(struct lguest *lg, void *b, unsigned long addr, unsigned bytes) +void __lgread(struct lg_cpu *cpu, void *b, unsigned long addr, unsigned bytes) { - if (!lguest_address_ok(lg, addr, bytes) - || copy_from_user(b, lg->mem_base + addr, bytes) != 0) { + if (!lguest_address_ok(cpu->lg, addr, bytes) + || copy_from_user(b, cpu->lg->mem_base + addr, bytes) != 0) { /* copy_from_user should do this, but as we rely on it... */ memset(b, 0, bytes); - kill_guest(lg, "bad read address %#lx len %u", addr, bytes); + kill_guest(cpu, "bad read address %#lx len %u", addr, bytes); } } /* This is the write (copy into guest) version. */ -void __lgwrite(struct lguest *lg, unsigned long addr, const void *b, +void __lgwrite(struct lg_cpu *cpu, unsigned long addr, const void *b, unsigned bytes) { - if (!lguest_address_ok(lg, addr, bytes) - || copy_to_user(lg->mem_base + addr, b, bytes) != 0) - kill_guest(lg, "bad write address %#lx len %u", addr, bytes); + if (!lguest_address_ok(cpu->lg, addr, bytes) + || copy_to_user(cpu->lg->mem_base + addr, b, bytes) != 0) + kill_guest(cpu, "bad write address %#lx len %u", addr, bytes); } /*:*/ @@ -176,10 +176,8 @@ void __lgwrite(struct lguest *lg, unsigned long addr, const void *b, * going around and around until something interesting happens. */ int run_guest(struct lg_cpu *cpu, unsigned long __user *user) { - struct lguest *lg = cpu->lg; - /* We stop running once the Guest is dead. */ - while (!lg->dead) { + while (!cpu->lg->dead) { /* First we run any hypercalls the Guest wants done. */ if (cpu->hcall) do_hypercalls(cpu); @@ -212,7 +210,7 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user) /* Just make absolutely sure the Guest is still alive. One of * those hypercalls could have been fatal, for example. */ - if (lg->dead) + if (cpu->lg->dead) break; /* If the Guest asked to be stopped, we sleep. The Guest's @@ -237,7 +235,7 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user) lguest_arch_handle_trap(cpu); } - if (lg->dead == ERR_PTR(-ERESTART)) + if (cpu->lg->dead == ERR_PTR(-ERESTART)) return -ERESTART; /* The Guest is dead => "No such file or directory" */ return -ENOENT; diff --git a/drivers/lguest/hypercalls.c b/drivers/lguest/hypercalls.c index 0471018d70..32666d0d95 100644 --- a/drivers/lguest/hypercalls.c +++ b/drivers/lguest/hypercalls.c @@ -31,8 +31,6 @@ * Or gets killed. Or, in the case of LHCALL_CRASH, both. */ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args) { - struct lguest *lg = cpu->lg; - switch (args->arg0) { case LHCALL_FLUSH_ASYNC: /* This call does nothing, except by breaking out of the Guest @@ -41,7 +39,7 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args) case LHCALL_LGUEST_INIT: /* You can't get here unless you're already initialized. Don't * do that. */ - kill_guest(lg, "already have lguest_data"); + kill_guest(cpu, "already have lguest_data"); break; case LHCALL_SHUTDOWN: { /* Shutdown is such a trivial hypercall that we do it in four @@ -49,11 +47,11 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args) char msg[128]; /* If the lgread fails, it will call kill_guest() itself; the * kill_guest() with the message will be ignored. */ - __lgread(lg, msg, args->arg1, sizeof(msg)); + __lgread(cpu, msg, args->arg1, sizeof(msg)); msg[sizeof(msg)-1] = '\0'; - kill_guest(lg, "CRASH: %s", msg); + kill_guest(cpu, "CRASH: %s", msg); if (args->arg2 == LGUEST_SHUTDOWN_RESTART) - lg->dead = ERR_PTR(-ERESTART); + cpu->lg->dead = ERR_PTR(-ERESTART); break; } case LHCALL_FLUSH_TLB: @@ -74,10 +72,10 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args) guest_set_stack(cpu, args->arg1, args->arg2, args->arg3); break; case LHCALL_SET_PTE: - guest_set_pte(lg, args->arg1, args->arg2, __pte(args->arg3)); + guest_set_pte(cpu, args->arg1, args->arg2, __pte(args->arg3)); break; case LHCALL_SET_PMD: - guest_set_pmd(lg, args->arg1, args->arg2); + guest_set_pmd(cpu->lg, args->arg1, args->arg2); break; case LHCALL_SET_CLOCKEVENT: guest_set_clockevent(cpu, args->arg1); @@ -96,7 +94,7 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args) default: /* It should be an architecture-specific hypercall. */ if (lguest_arch_do_hcall(cpu, args)) - kill_guest(lg, "Bad hypercall %li\n", args->arg0); + kill_guest(cpu, "Bad hypercall %li\n", args->arg0); } } /*:*/ @@ -112,10 +110,9 @@ static void do_async_hcalls(struct lg_cpu *cpu) { unsigned int i; u8 st[LHCALL_RING_SIZE]; - struct lguest *lg = cpu->lg; /* For simplicity, we copy the entire call status array in at once. */ - if (copy_from_user(&st, &lg->lguest_data->hcall_status, sizeof(st))) + if (copy_from_user(&st, &cpu->lg->lguest_data->hcall_status, sizeof(st))) return; /* We process "struct lguest_data"s hcalls[] ring once. */ @@ -137,9 +134,9 @@ static void do_async_hcalls(struct lg_cpu *cpu) /* Copy the hypercall arguments into a local copy of * the hcall_args struct. */ - if (copy_from_user(&args, &lg->lguest_data->hcalls[n], + if (copy_from_user(&args, &cpu->lg->lguest_data->hcalls[n], sizeof(struct hcall_args))) { - kill_guest(lg, "Fetching async hypercalls"); + kill_guest(cpu, "Fetching async hypercalls"); break; } @@ -147,8 +144,8 @@ static void do_async_hcalls(struct lg_cpu *cpu) do_hcall(cpu, &args); /* Mark the hypercall done. */ - if (put_user(0xFF, &lg->lguest_data->hcall_status[n])) { - kill_guest(lg, "Writing result for async hypercall"); + if (put_user(0xFF, &cpu->lg->lguest_data->hcall_status[n])) { + kill_guest(cpu, "Writing result for async hypercall"); break; } @@ -163,29 +160,28 @@ static void do_async_hcalls(struct lg_cpu *cpu) * Guest makes a hypercall, we end up here to set things up: */ static void initialize(struct lg_cpu *cpu) { - struct lguest *lg = cpu->lg; /* You can't do anything until you're initialized. The Guest knows the * rules, so we're unforgiving here. */ if (cpu->hcall->arg0 != LHCALL_LGUEST_INIT) { - kill_guest(lg, "hypercall %li before INIT", cpu->hcall->arg0); + kill_guest(cpu, "hypercall %li before INIT", cpu->hcall->arg0); return; } if (lguest_arch_init_hypercalls(cpu)) - kill_guest(lg, "bad guest page %p", lg->lguest_data); + kill_guest(cpu, "bad guest page %p", cpu->lg->lguest_data); /* The Guest tells us where we're not to deliver interrupts by putting * the range of addresses into "struct lguest_data". */ - if (get_user(lg->noirq_start, &lg->lguest_data->noirq_start) - || get_user(lg->noirq_end, &lg->lguest_data->noirq_end)) - kill_guest(lg, "bad guest page %p", lg->lguest_data); + if (get_user(cpu->lg->noirq_start, &cpu->lg->lguest_data->noirq_start) + || get_user(cpu->lg->noirq_end, &cpu->lg->lguest_data->noirq_end)) + kill_guest(cpu, "bad guest page %p", cpu->lg->lguest_data); /* We write the current time into the Guest's data page once so it can * set its clock. */ - write_timestamp(lg); + write_timestamp(cpu); /* page_tables.c will also do some setup. */ - page_table_guest_data_init(lg); + page_table_guest_data_init(cpu); /* This is the one case where the above accesses might have been the * first write to a Guest page. This may have caused a copy-on-write @@ -237,10 +233,11 @@ void do_hypercalls(struct lg_cpu *cpu) /* This routine supplies the Guest with time: it's used for wallclock time at * initial boot and as a rough time source if the TSC isn't available. */ -void write_timestamp(struct lguest *lg) +void write_timestamp(struct lg_cpu *cpu) { struct timespec now; ktime_get_real_ts(&now); - if (copy_to_user(&lg->lguest_data->time, &now, sizeof(struct timespec))) - kill_guest(lg, "Writing timestamp"); + if (copy_to_user(&cpu->lg->lguest_data->time, + &now, sizeof(struct timespec))) + kill_guest(cpu, "Writing timestamp"); } diff --git a/drivers/lguest/interrupts_and_traps.c b/drivers/lguest/interrupts_and_traps.c index 9ac7455ec7..32e97c1858 100644 --- a/drivers/lguest/interrupts_and_traps.c +++ b/drivers/lguest/interrupts_and_traps.c @@ -41,11 +41,11 @@ static int idt_present(u32 lo, u32 hi) /* We need a helper to "push" a value onto the Guest's stack, since that's a * big part of what delivering an interrupt does. */ -static void push_guest_stack(struct lguest *lg, unsigned long *gstack, u32 val) +static void push_guest_stack(struct lg_cpu *cpu, unsigned long *gstack, u32 val) { /* Stack grows upwards: move stack then write value. */ *gstack -= 4; - lgwrite(lg, *gstack, u32, val); + lgwrite(cpu, *gstack, u32, val); } /*H:210 The set_guest_interrupt() routine actually delivers the interrupt or @@ -65,7 +65,6 @@ static void set_guest_interrupt(struct lg_cpu *cpu, u32 lo, u32 hi, int has_err) unsigned long gstack, origstack; u32 eflags, ss, irq_enable; unsigned long virtstack; - struct lguest *lg = cpu->lg; /* There are two cases for interrupts: one where the Guest is already * in the kernel, and a more complex one where the Guest is in @@ -81,8 +80,8 @@ static void set_guest_interrupt(struct lg_cpu *cpu, u32 lo, u32 hi, int has_err) * stack: when the Guest does an "iret" back from the interrupt * handler the CPU will notice they're dropping privilege * levels and expect these here. */ - push_guest_stack(lg, &gstack, cpu->regs->ss); - push_guest_stack(lg, &gstack, cpu->regs->esp); + push_guest_stack(cpu, &gstack, cpu->regs->ss); + push_guest_stack(cpu, &gstack, cpu->regs->esp); } else { /* We're staying on the same Guest (kernel) stack. */ virtstack = cpu->regs->esp; @@ -96,20 +95,20 @@ static void set_guest_interrupt(struct lg_cpu *cpu, u32 lo, u32 hi, int has_err) * Guest's "irq_enabled" field into the eflags word: we saw the Guest * copy it back in "lguest_iret". */ eflags = cpu->regs->eflags; - if (get_user(irq_enable, &lg->lguest_data->irq_enabled) == 0 + if (get_user(irq_enable, &cpu->lg->lguest_data->irq_enabled) == 0 && !(irq_enable & X86_EFLAGS_IF)) eflags &= ~X86_EFLAGS_IF; /* An interrupt is expected to push three things on the stack: the old * "eflags" word, the old code segment, and the old instruction * pointer. */ - push_guest_stack(lg, &gstack, eflags); - push_guest_stack(lg, &gstack, cpu->regs->cs); - push_guest_stack(lg, &gstack, cpu->regs->eip); + push_guest_stack(cpu, &gstack, eflags); + push_guest_stack(cpu, &gstack, cpu->regs->cs); + push_guest_stack(cpu, &gstack, cpu->regs->eip); /* For the six traps which supply an error code, we push that, too. */ if (has_err) - push_guest_stack(lg, &gstack, cpu->regs->errcode); + push_guest_stack(cpu, &gstack, cpu->regs->errcode); /* Now we've pushed all the old state, we change the stack, the code * segment and the address to execute. */ @@ -121,8 +120,8 @@ static void set_guest_interrupt(struct lg_cpu *cpu, u32 lo, u32 hi, int has_err) /* There are two kinds of interrupt handlers: 0xE is an "interrupt * gate" which expects interrupts to be disabled on entry. */ if (idt_type(lo, hi) == 0xE) - if (put_user(0, &lg->lguest_data->irq_enabled)) - kill_guest(lg, "Disabling interrupts"); + if (put_user(0, &cpu->lg->lguest_data->irq_enabled)) + kill_guest(cpu, "Disabling interrupts"); } /*H:205 @@ -133,17 +132,16 @@ static void set_guest_interrupt(struct lg_cpu *cpu, u32 lo, u32 hi, int has_err) void maybe_do_interrupt(struct lg_cpu *cpu) { unsigned int irq; - struct lguest *lg = cpu->lg; DECLARE_BITMAP(blk, LGUEST_IRQS); struct desc_struct *idt; /* If the Guest hasn't even initialized yet, we can do nothing. */ - if (!lg->lguest_data) + if (!cpu->lg->lguest_data) return; /* Take our "irqs_pending" array and remove any interrupts the Guest * wants blocked: the result ends up in "blk". */ - if (copy_from_user(&blk, lg->lguest_data->blocked_interrupts, + if (copy_from_user(&blk, cpu->lg->lguest_data->blocked_interrupts, sizeof(blk))) return; @@ -157,19 +155,20 @@ void maybe_do_interrupt(struct lg_cpu *cpu) /* They may be in the middle of an iret, where they asked us never to * deliver interrupts. */ - if (cpu->regs->eip >= lg->noirq_start && cpu->regs->eip < lg->noirq_end) + if (cpu->regs->eip >= cpu->lg->noirq_start && + (cpu->regs->eip < cpu->lg->noirq_end)) return; /* If they're halted, interrupts restart them. */ if (cpu->halted) { /* Re-enable interrupts. */ - if (put_user(X86_EFLAGS_IF, &lg->lguest_data->irq_enabled)) - kill_guest(lg, "Re-enabling interrupts"); + if (put_user(X86_EFLAGS_IF, &cpu->lg->lguest_data->irq_enabled)) + kill_guest(cpu, "Re-enabling interrupts"); cpu->halted = 0; } else { /* Otherwise we check if they have interrupts disabled. */ u32 irq_enabled; - if (get_user(irq_enabled, &lg->lguest_data->irq_enabled)) + if (get_user(irq_enabled, &cpu->lg->lguest_data->irq_enabled)) irq_enabled = 0; if (!irq_enabled) return; @@ -194,7 +193,7 @@ void maybe_do_interrupt(struct lg_cpu *cpu) * did this more often, but it can actually be quite slow: doing it * here is a compromise which means at least it gets updated every * timer interrupt. */ - write_timestamp(lg); + write_timestamp(cpu); } /*:*/ @@ -315,10 +314,9 @@ void pin_stack_pages(struct lg_cpu *cpu) { unsigned int i; - struct lguest *lg = cpu->lg; /* Depending on the CONFIG_4KSTACKS option, the Guest can have one or * two pages of stack space. */ - for (i = 0; i < lg->stack_pages; i++) + for (i = 0; i < cpu->lg->stack_pages; i++) /* The stack grows *upwards*, so the address we're given is the * start of the page after the kernel stack. Subtract one to * get back onto the first stack page, and keep subtracting to @@ -339,10 +337,10 @@ void guest_set_stack(struct lg_cpu *cpu, u32 seg, u32 esp, unsigned int pages) /* You are not allowed have a stack segment with privilege level 0: bad * Guest! */ if ((seg & 0x3) != GUEST_PL) - kill_guest(cpu->lg, "bad stack segment %i", seg); + kill_guest(cpu, "bad stack segment %i", seg); /* We only expect one or two stack pages. */ if (pages > 2) - kill_guest(cpu->lg, "bad stack pages %u", pages); + kill_guest(cpu, "bad stack pages %u", pages); /* Save where the stack is, and how many pages */ cpu->ss1 = seg; cpu->esp1 = esp; @@ -356,7 +354,7 @@ void guest_set_stack(struct lg_cpu *cpu, u32 seg, u32 esp, unsigned int pages) /*H:235 This is the routine which actually checks the Guest's IDT entry and * transfers it into the entry in "struct lguest": */ -static void set_trap(struct lguest *lg, struct desc_struct *trap, +static void set_trap(struct lg_cpu *cpu, struct desc_struct *trap, unsigned int num, u32 lo, u32 hi) { u8 type = idt_type(lo, hi); @@ -369,7 +367,7 @@ static void set_trap(struct lguest *lg, struct desc_struct *trap, /* We only support interrupt and trap gates. */ if (type != 0xE && type != 0xF) - kill_guest(lg, "bad IDT type %i", type); + kill_guest(cpu, "bad IDT type %i", type); /* We only copy the handler address, present bit, privilege level and * type. The privilege level controls where the trap can be triggered @@ -399,9 +397,9 @@ void load_guest_idt_entry(struct lg_cpu *cpu, unsigned int num, u32 lo, u32 hi) /* Check that the Guest doesn't try to step outside the bounds. */ if (num >= ARRAY_SIZE(cpu->arch.idt)) - kill_guest(cpu->lg, "Setting idt entry %u", num); + kill_guest(cpu, "Setting idt entry %u", num); else - set_trap(cpu->lg, &cpu->arch.idt[num], num, lo, hi); + set_trap(cpu, &cpu->arch.idt[num], num, lo, hi); } /* The default entry for each interrupt points into the Switcher routines which diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h index 0d6f6435d7..b75ce3b17a 100644 --- a/drivers/lguest/lg.h +++ b/drivers/lguest/lg.h @@ -111,22 +111,22 @@ extern struct mutex lguest_lock; /* core.c: */ int lguest_address_ok(const struct lguest *lg, unsigned long addr, unsigned long len); -void __lgread(struct lguest *, void *, unsigned long, unsigned); -void __lgwrite(struct lguest *, unsigned long, const void *, unsigned); +void __lgread(struct lg_cpu *, void *, unsigned long, unsigned); +void __lgwrite(struct lg_cpu *, unsigned long, const void *, unsigned); /*H:035 Using memory-copy operations like that is usually inconvient, so we * have the following helper macros which read and write a specific type (often * an unsigned long). * * This reads into a variable of the given type then returns that. */ -#define lgread(lg, addr, type) \ - ({ type _v; __lgread((lg), &_v, (addr), sizeof(_v)); _v; }) +#define lgread(cpu, addr, type) \ + ({ type _v; __lgread((cpu), &_v, (addr), sizeof(_v)); _v; }) /* This checks that the variable is of the given type, then writes it out. */ -#define lgwrite(lg, addr, type, val) \ +#define lgwrite(cpu, addr, type, val) \ do { \ typecheck(type, val); \ - __lgwrite((lg), (addr), &(val), sizeof(val)); \ + __lgwrite((cpu), (addr), &(val), sizeof(val)); \ } while(0) /* (end of memory access helper routines) :*/ @@ -171,13 +171,13 @@ void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable); void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 i); void guest_pagetable_clear_all(struct lg_cpu *cpu); void guest_pagetable_flush_user(struct lg_cpu *cpu); -void guest_set_pte(struct lguest *lg, unsigned long gpgdir, +void guest_set_pte(struct lg_cpu *cpu, unsigned long gpgdir, unsigned long vaddr, pte_t val); void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages); int demand_page(struct lg_cpu *cpu, unsigned long cr2, int errcode); void pin_page(struct lg_cpu *cpu, unsigned long vaddr); unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr); -void page_table_guest_data_init(struct lguest *lg); +void page_table_guest_data_init(struct lg_cpu *cpu); /* /core.c: */ void lguest_arch_host_init(void); @@ -197,7 +197,7 @@ void lguest_device_remove(void); /* hypercalls.c: */ void do_hypercalls(struct lg_cpu *cpu); -void write_timestamp(struct lguest *lg); +void write_timestamp(struct lg_cpu *cpu); /*L:035 * Let's step aside for the moment, to study one important routine that's used @@ -223,12 +223,12 @@ void write_timestamp(struct lguest *lg); * Like any macro which uses an "if", it is safely wrapped in a run-once "do { * } while(0)". */ -#define kill_guest(lg, fmt...) \ +#define kill_guest(cpu, fmt...) \ do { \ - if (!(lg)->dead) { \ - (lg)->dead = kasprintf(GFP_ATOMIC, fmt); \ - if (!(lg)->dead) \ - (lg)->dead = ERR_PTR(-ENOMEM); \ + if (!(cpu)->lg->dead) { \ + (cpu)->lg->dead = kasprintf(GFP_ATOMIC, fmt); \ + if (!(cpu)->lg->dead) \ + (cpu)->lg->dead = ERR_PTR(-ENOMEM); \ } \ } while(0) /* (End of aside) :*/ diff --git a/drivers/lguest/page_tables.c b/drivers/lguest/page_tables.c index c9acafcab2..983e9020ce 100644 --- a/drivers/lguest/page_tables.c +++ b/drivers/lguest/page_tables.c @@ -68,17 +68,17 @@ static DEFINE_PER_CPU(pte_t *, switcher_pte_pages); * page directory entry (PGD) for that address. Since we keep track of several * page tables, the "i" argument tells us which one we're interested in (it's * usually the current one). */ -static pgd_t *spgd_addr(struct lguest *lg, u32 i, unsigned long vaddr) +static pgd_t *spgd_addr(struct lg_cpu *cpu, u32 i, unsigned long vaddr) { unsigned int index = pgd_index(vaddr); /* We kill any Guest trying to touch the Switcher addresses. */ if (index >= SWITCHER_PGD_INDEX) { - kill_guest(lg, "attempt to access switcher pages"); + kill_guest(cpu, "attempt to access switcher pages"); index = 0; } /* Return a pointer index'th pgd entry for the i'th page table. */ - return &lg->pgdirs[i].pgdir[index]; + return &cpu->lg->pgdirs[i].pgdir[index]; } /* This routine then takes the page directory entry returned above, which @@ -137,7 +137,7 @@ static unsigned long get_pfn(unsigned long virtpfn, int write) * entry can be a little tricky. The flags are (almost) the same, but the * Guest PTE contains a virtual page number: the CPU needs the real page * number. */ -static pte_t gpte_to_spte(struct lguest *lg, pte_t gpte, int write) +static pte_t gpte_to_spte(struct lg_cpu *cpu, pte_t gpte, int write) { unsigned long pfn, base, flags; @@ -148,7 +148,7 @@ static pte_t gpte_to_spte(struct lguest *lg, pte_t gpte, int write) flags = (pte_flags(gpte) & ~_PAGE_GLOBAL); /* The Guest's pages are offset inside the Launcher. */ - base = (unsigned long)lg->mem_base / PAGE_SIZE; + base = (unsigned long)cpu->lg->mem_base / PAGE_SIZE; /* We need a temporary "unsigned long" variable to hold the answer from * get_pfn(), because it returns 0xFFFFFFFF on failure, which wouldn't @@ -156,7 +156,7 @@ static pte_t gpte_to_spte(struct lguest *lg, pte_t gpte, int write) * page, given the virtual number. */ pfn = get_pfn(base + pte_pfn(gpte), write); if (pfn == -1UL) { - kill_guest(lg, "failed to get page %lu", pte_pfn(gpte)); + kill_guest(cpu, "failed to get page %lu", pte_pfn(gpte)); /* When we destroy the Guest, we'll go through the shadow page * tables and release_pte() them. Make sure we don't think * this one is valid! */ @@ -176,17 +176,18 @@ static void release_pte(pte_t pte) } /*:*/ -static void check_gpte(struct lguest *lg, pte_t gpte) +static void check_gpte(struct lg_cpu *cpu, pte_t gpte) { if ((pte_flags(gpte) & (_PAGE_PWT|_PAGE_PSE)) - || pte_pfn(gpte) >= lg->pfn_limit) - kill_guest(lg, "bad page table entry"); + || pte_pfn(gpte) >= cpu->lg->pfn_limit) + kill_guest(cpu, "bad page table entry"); } -static void check_gpgd(struct lguest *lg, pgd_t gpgd) +static void check_gpgd(struct lg_cpu *cpu, pgd_t gpgd) { - if ((pgd_flags(gpgd) & ~_PAGE_TABLE) || pgd_pfn(gpgd) >= lg->pfn_limit) - kill_guest(lg, "bad page directory entry"); + if ((pgd_flags(gpgd) & ~_PAGE_TABLE) || + (pgd_pfn(gpgd) >= cpu->lg->pfn_limit)) + kill_guest(cpu, "bad page directory entry"); } /*H:330 @@ -206,27 +207,26 @@ int demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode) unsigned long gpte_ptr; pte_t gpte; pte_t *spte; - struct lguest *lg = cpu->lg; /* First step: get the top-level Guest page table entry. */ - gpgd = lgread(lg, gpgd_addr(cpu, vaddr), pgd_t); + gpgd = lgread(cpu, gpgd_addr(cpu, vaddr), pgd_t); /* Toplevel not present? We can't map it in. */ if (!(pgd_flags(gpgd) & _PAGE_PRESENT)) return 0; /* Now look at the matching shadow entry. */ - spgd = spgd_addr(lg, cpu->cpu_pgd, vaddr); + spgd = spgd_addr(cpu, cpu->cpu_pgd, vaddr); if (!(pgd_flags(*spgd) & _PAGE_PRESENT)) { /* No shadow entry: allocate a new shadow PTE page. */ unsigned long ptepage = get_zeroed_page(GFP_KERNEL); /* This is not really the Guest's fault, but killing it is * simple for this corner case. */ if (!ptepage) { - kill_guest(lg, "out of memory allocating pte page"); + kill_guest(cpu, "out of memory allocating pte page"); return 0; } /* We check that the Guest pgd is OK. */ - check_gpgd(lg, gpgd); + check_gpgd(cpu, gpgd); /* And we copy the flags to the shadow PGD entry. The page * number in the shadow PGD is the page we just allocated. */ *spgd = __pgd(__pa(ptepage) | pgd_flags(gpgd)); @@ -235,7 +235,7 @@ int demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode) /* OK, now we look at the lower level in the Guest page table: keep its * address, because we might update it later. */ gpte_ptr = gpte_addr(gpgd, vaddr); - gpte = lgread(lg, gpte_ptr, pte_t); + gpte = lgread(cpu, gpte_ptr, pte_t); /* If this page isn't in the Guest page tables, we can't page it in. */ if (!(pte_flags(gpte) & _PAGE_PRESENT)) @@ -252,7 +252,7 @@ int demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode) /* Check that the Guest PTE flags are OK, and the page number is below * the pfn_limit (ie. not mapping the Launcher binary). */ - check_gpte(lg, gpte); + check_gpte(cpu, gpte); /* Add the _PAGE_ACCESSED and (for a write) _PAGE_DIRTY flag */ gpte = pte_mkyoung(gpte); @@ -268,17 +268,17 @@ int demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode) /* If this is a write, we insist that the Guest page is writable (the * final arg to gpte_to_spte()). */ if (pte_dirty(gpte)) - *spte = gpte_to_spte(lg, gpte, 1); + *spte = gpte_to_spte(cpu, gpte, 1); else /* If this is a read, don't set the "writable" bit in the page * table entry, even if the Guest says it's writable. That way * we will come back here when a write does actually occur, so * we can update the Guest's _PAGE_DIRTY flag. */ - *spte = gpte_to_spte(lg, pte_wrprotect(gpte), 0); + *spte = gpte_to_spte(cpu, pte_wrprotect(gpte), 0); /* Finally, we write the Guest PTE entry back: we've set the * _PAGE_ACCESSED and maybe the _PAGE_DIRTY flags. */ - lgwrite(lg, gpte_ptr, pte_t, gpte); + lgwrite(cpu, gpte_ptr, pte_t, gpte); /* The fault is fixed, the page table is populated, the mapping * manipulated, the result returned and the code complete. A small @@ -303,7 +303,7 @@ static int page_writable(struct lg_cpu *cpu, unsigned long vaddr) unsigned long flags; /* Look at the current top level entry: is it present? */ - spgd = spgd_addr(cpu->lg, cpu->cpu_pgd, vaddr); + spgd = spgd_addr(cpu, cpu->cpu_pgd, vaddr); if (!(pgd_flags(*spgd) & _PAGE_PRESENT)) return 0; @@ -320,7 +320,7 @@ static int page_writable(struct lg_cpu *cpu, unsigned long vaddr) void pin_page(struct lg_cpu *cpu, unsigned long vaddr) { if (!page_writable(cpu, vaddr) && !demand_page(cpu, vaddr, 2)) - kill_guest(cpu->lg, "bad stack page %#lx", vaddr); + kill_guest(cpu, "bad stack page %#lx", vaddr); } /*H:450 If we chase down the release_pgd() code, it looks like this: */ @@ -372,14 +372,14 @@ unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr) pte_t gpte; /* First step: get the top-level Guest page table entry. */ - gpgd = lgread(cpu->lg, gpgd_addr(cpu, vaddr), pgd_t); + gpgd = lgread(cpu, gpgd_addr(cpu, vaddr), pgd_t); /* Toplevel not present? We can't map it in. */ if (!(pgd_flags(gpgd) & _PAGE_PRESENT)) - kill_guest(cpu->lg, "Bad address %#lx", vaddr); + kill_guest(cpu, "Bad address %#lx", vaddr); - gpte = lgread(cpu->lg, gpte_addr(gpgd, vaddr), pte_t); + gpte = lgread(cpu, gpte_addr(gpgd, vaddr), pte_t); if (!(pte_flags(gpte) & _PAGE_PRESENT)) - kill_guest(cpu->lg, "Bad address %#lx", vaddr); + kill_guest(cpu, "Bad address %#lx", vaddr); return pte_pfn(gpte) * PAGE_SIZE | (vaddr & ~PAGE_MASK); } @@ -404,16 +404,16 @@ static unsigned int new_pgdir(struct lg_cpu *cpu, int *blank_pgdir) { unsigned int next; - struct lguest *lg = cpu->lg; /* We pick one entry at random to throw out. Choosing the Least * Recently Used might be better, but this is easy. */ - next = random32() % ARRAY_SIZE(lg->pgdirs); + next = random32() % ARRAY_SIZE(cpu->lg->pgdirs); /* If it's never been allocated at all before, try now. */ - if (!lg->pgdirs[next].pgdir) { - lg->pgdirs[next].pgdir = (pgd_t *)get_zeroed_page(GFP_KERNEL); + if (!cpu->lg->pgdirs[next].pgdir) { + cpu->lg->pgdirs[next].pgdir = + (pgd_t *)get_zeroed_page(GFP_KERNEL); /* If the allocation fails, just keep using the one we have */ - if (!lg->pgdirs[next].pgdir) + if (!cpu->lg->pgdirs[next].pgdir) next = cpu->cpu_pgd; else /* This is a blank page, so there are no kernel @@ -421,9 +421,9 @@ static unsigned int new_pgdir(struct lg_cpu *cpu, *blank_pgdir = 1; } /* Record which Guest toplevel this shadows. */ - lg->pgdirs[next].gpgdir = gpgdir; + cpu->lg->pgdirs[next].gpgdir = gpgdir; /* Release all the non-kernel mappings. */ - flush_user_mappings(lg, next); + flush_user_mappings(cpu->lg, next); return next; } @@ -436,13 +436,12 @@ static unsigned int new_pgdir(struct lg_cpu *cpu, void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable) { int newpgdir, repin = 0; - struct lguest *lg = cpu->lg; /* Look to see if we have this one already. */ - newpgdir = find_pgdir(lg, pgtable); + newpgdir = find_pgdir(cpu->lg, pgtable); /* If not, we allocate or mug an existing one: if it's a fresh one, * repin gets set to 1. */ - if (newpgdir == ARRAY_SIZE(lg->pgdirs)) + if (newpgdir == ARRAY_SIZE(cpu->lg->pgdirs)) newpgdir = new_pgdir(cpu, pgtable, &repin); /* Change the current pgd index to the new one. */ cpu->cpu_pgd = newpgdir; @@ -499,11 +498,11 @@ void guest_pagetable_clear_all(struct lg_cpu *cpu) * _PAGE_ACCESSED then we can put a read-only PTE entry in immediately, and if * they set _PAGE_DIRTY then we can put a writable PTE entry in immediately. */ -static void do_set_pte(struct lguest *lg, int idx, +static void do_set_pte(struct lg_cpu *cpu, int idx, unsigned long vaddr, pte_t gpte) { /* Look up the matching shadow page directory entry. */ - pgd_t *spgd = spgd_addr(lg, idx, vaddr); + pgd_t *spgd = spgd_addr(cpu, idx, vaddr); /* If the top level isn't present, there's no entry to update. */ if (pgd_flags(*spgd) & _PAGE_PRESENT) { @@ -515,8 +514,8 @@ static void do_set_pte(struct lguest *lg, int idx, * as well put that entry they've given us in now. This shaves * 10% off a copy-on-write micro-benchmark. */ if (pte_flags(gpte) & (_PAGE_DIRTY | _PAGE_ACCESSED)) { - check_gpte(lg, gpte); - *spte = gpte_to_spte(lg, gpte, + check_gpte(cpu, gpte); + *spte = gpte_to_spte(cpu, gpte, pte_flags(gpte) & _PAGE_DIRTY); } else /* Otherwise kill it and we can demand_page() it in @@ -535,22 +534,22 @@ static void do_set_pte(struct lguest *lg, int idx, * * The benefit is that when we have to track a new page table, we can copy keep * all the kernel mappings. This speeds up context switch immensely. */ -void guest_set_pte(struct lguest *lg, +void guest_set_pte(struct lg_cpu *cpu, unsigned long gpgdir, unsigned long vaddr, pte_t gpte) { /* Kernel mappings must be changed on all top levels. Slow, but * doesn't happen often. */ - if (vaddr >= lg->kernel_address) { + if (vaddr >= cpu->lg->kernel_address) { unsigned int i; - for (i = 0; i < ARRAY_SIZE(lg->pgdirs); i++) - if (lg->pgdirs[i].pgdir) - do_set_pte(lg, i, vaddr, gpte); + for (i = 0; i < ARRAY_SIZE(cpu->lg->pgdirs); i++) + if (cpu->lg->pgdirs[i].pgdir) + do_set_pte(cpu, i, vaddr, gpte); } else { /* Is this page table one we have a shadow for? */ - int pgdir = find_pgdir(lg, gpgdir); - if (pgdir != ARRAY_SIZE(lg->pgdirs)) + int pgdir = find_pgdir(cpu->lg, gpgdir); + if (pgdir != ARRAY_SIZE(cpu->lg->pgdirs)) /* If so, do the update. */ - do_set_pte(lg, pgdir, vaddr, gpte); + do_set_pte(cpu, pgdir, vaddr, gpte); } } @@ -601,21 +600,23 @@ int init_guest_pagetable(struct lguest *lg, unsigned long pgtable) } /* When the Guest calls LHCALL_LGUEST_INIT we do more setup. */ -void page_table_guest_data_init(struct lguest *lg) +void page_table_guest_data_init(struct lg_cpu *cpu) { /* We get the kernel address: above this is all kernel memory. */ - if (get_user(lg->kernel_address, &lg->lguest_data->kernel_address) + if (get_user(cpu->lg->kernel_address, + &cpu->lg->lguest_data->kernel_address) /* We tell the Guest that it can't use the top 4MB of virtual * addresses used by the Switcher. */ - || put_user(4U*1024*1024, &lg->lguest_data->reserve_mem) - || put_user(lg->pgdirs[0].gpgdir, &lg->lguest_data->pgdir)) - kill_guest(lg, "bad guest page %p", lg->lguest_data); + || put_user(4U*1024*1024, &cpu->lg->lguest_data->reserve_mem) + || put_user(cpu->lg->pgdirs[0].gpgdir, &cpu->lg->lguest_data->pgdir)) + kill_guest(cpu, "bad guest page %p", cpu->lg->lguest_data); /* In flush_user_mappings() we loop from 0 to * "pgd_index(lg->kernel_address)". This assumes it won't hit the * Switcher mappings, so check that now. */ - if (pgd_index(lg->kernel_address) >= SWITCHER_PGD_INDEX) - kill_guest(lg, "bad kernel address %#lx", lg->kernel_address); + if (pgd_index(cpu->lg->kernel_address) >= SWITCHER_PGD_INDEX) + kill_guest(cpu, "bad kernel address %#lx", + cpu->lg->kernel_address); } /* When a Guest dies, our cleanup is fairly simple. */ diff --git a/drivers/lguest/segments.c b/drivers/lguest/segments.c index 635f54c719..ec6aa3f1c3 100644 --- a/drivers/lguest/segments.c +++ b/drivers/lguest/segments.c @@ -148,14 +148,13 @@ void copy_gdt(const struct lg_cpu *cpu, struct desc_struct *gdt) * We copy it from the Guest and tweak the entries. */ void load_guest_gdt(struct lg_cpu *cpu, unsigned long table, u32 num) { - struct lguest *lg = cpu->lg; /* We assume the Guest has the same number of GDT entries as the * Host, otherwise we'd have to dynamically allocate the Guest GDT. */ if (num > ARRAY_SIZE(cpu->arch.gdt)) - kill_guest(lg, "too many gdt entries %i", num); + kill_guest(cpu, "too many gdt entries %i", num); /* We read the whole thing in, then fix it up. */ - __lgread(lg, cpu->arch.gdt, table, num * sizeof(cpu->arch.gdt[0])); + __lgread(cpu, cpu->arch.gdt, table, num * sizeof(cpu->arch.gdt[0])); fixup_gdt_table(cpu, 0, ARRAY_SIZE(cpu->arch.gdt)); /* Mark that the GDT changed so the core knows it has to copy it again, * even if the Guest is run on the same CPU. */ @@ -169,9 +168,8 @@ void load_guest_gdt(struct lg_cpu *cpu, unsigned long table, u32 num) void guest_load_tls(struct lg_cpu *cpu, unsigned long gtls) { struct desc_struct *tls = &cpu->arch.gdt[GDT_ENTRY_TLS_MIN]; - struct lguest *lg = cpu->lg; - __lgread(lg, tls, gtls, sizeof(*tls)*GDT_ENTRY_TLS_ENTRIES); + __lgread(cpu, tls, gtls, sizeof(*tls)*GDT_ENTRY_TLS_ENTRIES); fixup_gdt_table(cpu, GDT_ENTRY_TLS_MIN, GDT_ENTRY_TLS_MAX+1); /* Note that just the TLS entries have changed. */ cpu->changed |= CHANGED_GDT_TLS; diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c index fd6a851244..e9c3ba8aa1 100644 --- a/drivers/lguest/x86/core.c +++ b/drivers/lguest/x86/core.c @@ -117,7 +117,6 @@ static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages) { /* This is a dummy value we need for GCC's sake. */ unsigned int clobber; - struct lguest *lg = cpu->lg; /* Copy the guest-specific information into this CPU's "struct * lguest_pages". */ @@ -144,7 +143,7 @@ static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages) * 0-th argument above, ie "a"). %ebx contains the * physical address of the Guest's top-level page * directory. */ - : "0"(pages), "1"(__pa(lg->pgdirs[cpu->cpu_pgd].pgdir)) + : "0"(pages), "1"(__pa(cpu->lg->pgdirs[cpu->cpu_pgd].pgdir)) /* We tell gcc that all these registers could change, * which means we don't have to save and restore them in * the Switcher. */ @@ -217,7 +216,6 @@ void lguest_arch_run_guest(struct lg_cpu *cpu) * instructions and skip over it. We return true if we did. */ static int emulate_insn(struct lg_cpu *cpu) { - struct lguest *lg = cpu->lg; u8 insn; unsigned int insnlen = 0, in = 0, shift = 0; /* The eip contains the *virtual* address of the Guest's instruction: @@ -231,7 +229,7 @@ static int emulate_insn(struct lg_cpu *cpu) return 0; /* Decoding x86 instructions is icky. */ - insn = lgread(lg, physaddr, u8); + insn = lgread(cpu, physaddr, u8); /* 0x66 is an "operand prefix". It means it's using the upper 16 bits of the eax register. */ @@ -239,7 +237,7 @@ static int emulate_insn(struct lg_cpu *cpu) shift = 16; /* The instruction is 1 byte so far, read the next byte. */ insnlen = 1; - insn = lgread(lg, physaddr + insnlen, u8); + insn = lgread(cpu, physaddr + insnlen, u8); } /* We can ignore the lower bit for the moment and decode the 4 opcodes @@ -283,7 +281,6 @@ static int emulate_insn(struct lg_cpu *cpu) /*H:050 Once we've re-enabled interrupts, we look at why the Guest exited. */ void lguest_arch_handle_trap(struct lg_cpu *cpu) { - struct lguest *lg = cpu->lg; switch (cpu->regs->trapnum) { case 13: /* We've intercepted a General Protection Fault. */ /* Check if this was one of those annoying IN or OUT @@ -315,9 +312,10 @@ void lguest_arch_handle_trap(struct lg_cpu *cpu) * Note that if the Guest were really messed up, this could * happen before it's done the LHCALL_LGUEST_INIT hypercall, so * lg->lguest_data could be NULL */ - if (lg->lguest_data && - put_user(cpu->arch.last_pagefault, &lg->lguest_data->cr2)) - kill_guest(lg, "Writing cr2"); + if (cpu->lg->lguest_data && + put_user(cpu->arch.last_pagefault, + &cpu->lg->lguest_data->cr2)) + kill_guest(cpu, "Writing cr2"); break; case 7: /* We've intercepted a Device Not Available fault. */ /* If the Guest doesn't want to know, we already restored the @@ -345,7 +343,7 @@ void lguest_arch_handle_trap(struct lg_cpu *cpu) /* If the Guest doesn't have a handler (either it hasn't * registered any yet, or it's one of the faults we don't let * it handle), it dies with a cryptic error message. */ - kill_guest(lg, "unhandled trap %li at %#lx (%#lx)", + kill_guest(cpu, "unhandled trap %li at %#lx (%#lx)", cpu->regs->trapnum, cpu->regs->eip, cpu->regs->trapnum == 14 ? cpu->arch.last_pagefault : cpu->regs->errcode); @@ -514,11 +512,11 @@ int lguest_arch_do_hcall(struct lg_cpu *cpu, struct hcall_args *args) int lguest_arch_init_hypercalls(struct lg_cpu *cpu) { u32 tsc_speed; - struct lguest *lg = cpu->lg; /* The pointer to the Guest's "struct lguest_data" is the only * argument. We check that address now. */ - if (!lguest_address_ok(lg, cpu->hcall->arg1, sizeof(*lg->lguest_data))) + if (!lguest_address_ok(cpu->lg, cpu->hcall->arg1, + sizeof(*cpu->lg->lguest_data))) return -EFAULT; /* Having checked it, we simply set lg->lguest_data to point straight @@ -526,7 +524,7 @@ int lguest_arch_init_hypercalls(struct lg_cpu *cpu) * copy_to_user/from_user from now on, instead of lgread/write. I put * this in to show that I'm not immune to writing stupid * optimizations. */ - lg->lguest_data = lg->mem_base + cpu->hcall->arg1; + cpu->lg->lguest_data = cpu->lg->mem_base + cpu->hcall->arg1; /* We insist that the Time Stamp Counter exist and doesn't change with * cpu frequency. Some devious chip manufacturers decided that TSC @@ -539,12 +537,12 @@ int lguest_arch_init_hypercalls(struct lg_cpu *cpu) tsc_speed = tsc_khz; else tsc_speed = 0; - if (put_user(tsc_speed, &lg->lguest_data->tsc_khz)) + if (put_user(tsc_speed, &cpu->lg->lguest_data->tsc_khz)) return -EFAULT; /* The interrupt code might not like the system call vector. */ - if (!check_syscall_vector(lg)) - kill_guest(lg, "bad syscall vector"); + if (!check_syscall_vector(cpu->lg)) + kill_guest(cpu, "bad syscall vector"); return 0; } -- 2.39.5