X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Flguest%2Flguest_user.c;h=b184652e45d7811f9b518b79b112021f1eeaa079;hb=c18acd73ffc209def08003a1927473096f66c5ad;hp=80d1b58c76986b9d245637e4e29999793260ddcd;hpb=715dad5992b1466320c1ac674db46297e57acf21;p=linux-2.6-omap-h63xx.git diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c index 80d1b58c769..b184652e45d 100644 --- a/drivers/lguest/lguest_user.c +++ b/drivers/lguest/lguest_user.c @@ -1,49 +1,18 @@ /*P:200 This contains all the /dev/lguest code, whereby the userspace launcher * controls and communicates with the Guest. For example, the first write will - * tell us the memory size, pagetable, entry point and kernel address offset. - * A read will run the Guest until a signal is pending (-EINTR), or the Guest - * does a DMA out to the Launcher. Writes are also used to get a DMA buffer - * registered by the Guest and to send the Guest an interrupt. :*/ + * tell us the Guest's memory layout, pagetable, entry point and kernel address + * offset. A read will run the Guest until something happens, such as a signal + * or the Guest doing a DMA out to the Launcher. Writes are also used to get a + * DMA buffer registered by the Guest and to send the Guest an interrupt. :*/ #include #include #include #include "lg.h" -/*L:030 setup_regs() doesn't really belong in this file, but it gives us an - * early glimpse deeper into the Host so it's worth having here. - * - * Most of the Guest's registers are left alone: we used get_zeroed_page() to - * allocate the structure, so they will be 0. */ -static void setup_regs(struct lguest_regs *regs, unsigned long start) -{ - /* There are four "segment" registers which the Guest needs to boot: - * The "code segment" register (cs) refers to the kernel code segment - * __KERNEL_CS, and the "data", "extra" and "stack" segment registers - * refer to the kernel data segment __KERNEL_DS. - * - * The privilege level is packed into the lower bits. The Guest runs - * at privilege level 1 (GUEST_PL).*/ - regs->ds = regs->es = regs->ss = __KERNEL_DS|GUEST_PL; - regs->cs = __KERNEL_CS|GUEST_PL; - - /* The "eflags" register contains miscellaneous flags. Bit 1 (0x002) - * is supposed to always be "1". Bit 9 (0x200) controls whether - * interrupts are enabled. We always leave interrupts enabled while - * running the Guest. */ - regs->eflags = 0x202; - - /* The "Extended Instruction Pointer" register says where the Guest is - * running. */ - regs->eip = start; - - /* %esi points to our boot information, at physical address 0, so don't - * touch it. */ -} - /*L:310 To send DMA into the Guest, the Launcher needs to be able to ask for a * DMA buffer. This is done by writing LHREQ_GETDMA and the key to * /dev/lguest. */ -static long user_get_dma(struct lguest *lg, const u32 __user *input) +static long user_get_dma(struct lguest *lg, const unsigned long __user *input) { unsigned long key, udma, irq; @@ -67,7 +36,7 @@ static long user_get_dma(struct lguest *lg, const u32 __user *input) /*L:315 To force the Guest to stop running and return to the Launcher, the * Waker sets writes LHREQ_BREAK and the value "1" to /dev/lguest. The * Launcher then writes LHREQ_BREAK and "0" to release the Waker. */ -static int break_guest_out(struct lguest *lg, const u32 __user *input) +static int break_guest_out(struct lguest *lg, const unsigned long __user *input) { unsigned long on; @@ -90,9 +59,9 @@ static int break_guest_out(struct lguest *lg, const u32 __user *input) /*L:050 Sending an interrupt is done by writing LHREQ_IRQ and an interrupt * number to /dev/lguest. */ -static int user_send_irq(struct lguest *lg, const u32 __user *input) +static int user_send_irq(struct lguest *lg, const unsigned long __user *input) { - u32 irq; + unsigned long irq; if (get_user(irq, input) != 0) return -EFAULT; @@ -142,8 +111,10 @@ static ssize_t read(struct file *file, char __user *user, size_t size,loff_t*o) return run_guest(lg, (unsigned long __user *)user); } -/*L:020 The initialization write supplies 4 32-bit values (in addition to the - * 32-bit LHREQ_INITIALIZE value). These are: +/*L:020 The initialization write supplies 5 pointer sized (32 or 64 bit) + * values (in addition to the LHREQ_INITIALIZE value). These are: + * + * base: The start of the Guest-physical memory inside the Launcher memory. * * pfnlimit: The highest (Guest-physical) page number the Guest should be * allowed to access. The Launcher has to live in Guest memory, so it sets @@ -160,16 +131,16 @@ static ssize_t read(struct file *file, char __user *user, size_t size,loff_t*o) * quickly converted from physical to virtual by adding PAGE_OFFSET. It's * 0xC0000000 (3G) by default, but it's configurable at kernel build time. */ -static int initialize(struct file *file, const u32 __user *input) +static int initialize(struct file *file, const unsigned long __user *input) { /* "struct lguest" contains everything we (the Host) know about a * Guest. */ struct lguest *lg; - int err, i; - u32 args[4]; + int err; + unsigned long args[5]; - /* We grab the Big Lguest lock, which protects the global array - * "lguests" and multiple simultaneous initializations. */ + /* We grab the Big Lguest lock, which protects against multiple + * simultaneous initializations. */ mutex_lock(&lguest_lock); /* You can't initialize twice! Close the device and start again... */ if (file->private_data) { @@ -182,20 +153,16 @@ static int initialize(struct file *file, const u32 __user *input) goto unlock; } - /* Find an unused guest. */ - i = find_free_guest(); - if (i < 0) { - err = -ENOSPC; + lg = kzalloc(sizeof(*lg), GFP_KERNEL); + if (!lg) { + err = -ENOMEM; goto unlock; } - /* OK, we have an index into the "lguest" array: "lg" is a convenient - * pointer. */ - lg = &lguests[i]; /* Populate the easy fields of our "struct lguest" */ - lg->guestid = i; - lg->pfn_limit = args[0]; - lg->page_offset = args[3]; + lg->mem_base = (void __user *)(long)args[0]; + lg->pfn_limit = args[1]; + lg->page_offset = args[4]; /* We need a complete page for the Guest registers: they are accessible * to the Guest and we can only grant it access to whole pages. */ @@ -210,17 +177,13 @@ static int initialize(struct file *file, const u32 __user *input) /* Initialize the Guest's shadow page tables, using the toplevel * address the Launcher gave us. This allocates memory, so can * fail. */ - err = init_guest_pagetable(lg, args[1]); + err = init_guest_pagetable(lg, args[2]); if (err) goto free_regs; /* Now we initialize the Guest's registers, handing it the start * address. */ - setup_regs(lg->regs, args[2]); - - /* There are a couple of GDT entries the Guest expects when first - * booting. */ - setup_guest_gdt(lg); + lguest_arch_setup_regs(lg, args[3]); /* The timer for lguest's clock needs initialization. */ init_clockdev(lg); @@ -261,17 +224,18 @@ unlock: * start with a 32 bit number: for the first write this must be * LHREQ_INITIALIZE to set up the Guest. After that the Launcher can use * writes of other values to get DMA buffers and send interrupts. */ -static ssize_t write(struct file *file, const char __user *input, +static ssize_t write(struct file *file, const char __user *in, size_t size, loff_t *off) { /* Once the guest is initialized, we hold the "struct lguest" in the * file private data. */ struct lguest *lg = file->private_data; - u32 req; + const unsigned long __user *input = (const unsigned long __user *)in; + unsigned long req; if (get_user(req, input) != 0) return -EFAULT; - input += sizeof(req); + input++; /* If you haven't initialized, you must do that first. */ if (req != LHREQ_INITIALIZE && !lg) @@ -287,13 +251,13 @@ static ssize_t write(struct file *file, const char __user *input, switch (req) { case LHREQ_INITIALIZE: - return initialize(file, (const u32 __user *)input); + return initialize(file, input); case LHREQ_GETDMA: - return user_get_dma(lg, (const u32 __user *)input); + return user_get_dma(lg, input); case LHREQ_IRQ: - return user_send_irq(lg, (const u32 __user *)input); + return user_send_irq(lg, input); case LHREQ_BREAK: - return break_guest_out(lg, (const u32 __user *)input); + return break_guest_out(lg, input); default: return -EINVAL; }