Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus (a7e1aabb) · Commits · e / devices / android_kernel_xiaomi_markw

Documentation/virtual/lguest/lguest.c

+16 −31

Original line number	Original line	Diff line number	Diff line
	@@ -51,7 +51,7 @@
	#include <asm/bootparam.h>		#include <asm/bootparam.h>
	#include "../../../include/linux/lguest_launcher.h"		#include "../../../include/linux/lguest_launcher.h"
	/*L:110		/*L:110
	* We can ignore the 42 include files we need for this program, but I do want		* We can ignore the 43 include files we need for this program, but I do want
	* to draw attention to the use of kernel-style types.		* to draw attention to the use of kernel-style types.
	*		*
	* As Linus said, "C is a Spartan language, and so should your naming be." I		* As Linus said, "C is a Spartan language, and so should your naming be." I
	@@ -65,7 +65,6 @@ typedef uint16_t u16;
	typedef uint8_t u8;		typedef uint8_t u8;
	/:/		/:/

	#define PAGE_PRESENT 0x7 /* Present, RW, Execute */
	#define BRIDGE_PFX "bridge:"		#define BRIDGE_PFX "bridge:"
	#ifndef SIOCBRADDIF		#ifndef SIOCBRADDIF
	#define SIOCBRADDIF 0x89a2 /* add interface to bridge */		#define SIOCBRADDIF 0x89a2 /* add interface to bridge */
	@@ -861,8 +860,10 @@ static void console_output(struct virtqueue *vq)
	/* writev can return a partial write, so we loop here. */		/* writev can return a partial write, so we loop here. */
	while (!iov_empty(iov, out)) {		while (!iov_empty(iov, out)) {
	int len = writev(STDOUT_FILENO, iov, out);		int len = writev(STDOUT_FILENO, iov, out);
	if (len <= 0)		if (len <= 0) {
	err(1, "Write to stdout gave %i", len);		warn("Write to stdout gave %i (%d)", len, errno);
			break;
			}
	iov_consume(iov, out, len);		iov_consume(iov, out, len);
	}		}

	@@ -898,7 +899,7 @@ static void net_output(struct virtqueue *vq)
	* same format: what a coincidence!		* same format: what a coincidence!
	*/		*/
	if (writev(net_info->tunfd, iov, out) < 0)		if (writev(net_info->tunfd, iov, out) < 0)
	errx(1, "Write to tun failed?");		warnx("Write to tun failed (%d)?", errno);

	/*		/*
	* Done with that one; wait_for_vq_desc() will send the interrupt if		* Done with that one; wait_for_vq_desc() will send the interrupt if
	@@ -955,7 +956,7 @@ static void net_input(struct virtqueue *vq)
	*/		*/
	len = readv(net_info->tunfd, iov, in);		len = readv(net_info->tunfd, iov, in);
	if (len <= 0)		if (len <= 0)
	err(1, "Failed to read from tun.");		warn("Failed to read from tun (%d).", errno);

	/*		/*
	* Mark that packet buffer as used, but don't interrupt here. We want		* Mark that packet buffer as used, but don't interrupt here. We want
	@@ -1093,8 +1094,9 @@ static void update_device_status(struct device *dev)
	warnx("Device %s configuration FAILED", dev->name);		warnx("Device %s configuration FAILED", dev->name);
	if (dev->running)		if (dev->running)
	reset_device(dev);		reset_device(dev);
	} else if (dev->desc->status & VIRTIO_CONFIG_S_DRIVER_OK) {		} else {
	if (!dev->running)		if (dev->running)
			err(1, "Device %s features finalized twice", dev->name);
	start_device(dev);		start_device(dev);
	}		}
	}		}
	@@ -1120,25 +1122,11 @@ static void handle_output(unsigned long addr)
	return;		return;
	}		}

	/*		/* Devices should not be used before features are finalized. */
	* Devices can be used before status is set to DRIVER_OK.
	* The original plan was that they would never do this: they
	* would always finish setting up their status bits before
	* actually touching the virtqueues. In practice, we allowed
	* them to, and they do (eg. the disk probes for partition
	* tables as part of initialization).
	*
	* If we see this, we start the device: once it's running, we
	* expect the device to catch all the notifications.
	*/
	for (vq = i->vq; vq; vq = vq->next) {		for (vq = i->vq; vq; vq = vq->next) {
	if (addr != vq->config.pfn*getpagesize())		if (addr != vq->config.pfn*getpagesize())
	continue;		continue;
	if (i->running)		errx(1, "Notification on %s before setup!", i->name);
	errx(1, "Notification on running %s", i->name);
	/* This just calls create_thread() for each virtqueue */
	start_device(i);
	return;
	}		}
	}		}

	@@ -1370,7 +1358,7 @@ static void setup_console(void)
	* --sharenet=<name> option which opens or creates a named pipe. This can be		* --sharenet=<name> option which opens or creates a named pipe. This can be
	* used to send packets to another guest in a 1:1 manner.		* used to send packets to another guest in a 1:1 manner.
	*		*
	* More sopisticated is to use one of the tools developed for project like UML		* More sophisticated is to use one of the tools developed for project like UML
	* to do networking.		* to do networking.
	*		*
	* Faster is to do virtio bonding in kernel. Doing this 1:1 would be		* Faster is to do virtio bonding in kernel. Doing this 1:1 would be
	@@ -1380,7 +1368,7 @@ static void setup_console(void)
	* multiple inter-guest channels behind one interface, although it would		* multiple inter-guest channels behind one interface, although it would
	* require some manner of hotplugging new virtio channels.		* require some manner of hotplugging new virtio channels.
	*		*
	* Finally, we could implement a virtio network switch in the kernel.		* Finally, we could use a virtio network switch in the kernel, ie. vhost.
	:*/		:*/

	static u32 str2ip(const char *ipaddr)		static u32 str2ip(const char *ipaddr)
	@@ -2017,10 +2005,7 @@ int main(int argc, char *argv[])
	/* Tell the entry path not to try to reload segment registers. */		/* Tell the entry path not to try to reload segment registers. */
	boot->hdr.loadflags \|= KEEP_SEGMENTS;		boot->hdr.loadflags \|= KEEP_SEGMENTS;

	/*		/* We tell the kernel to initialize the Guest. */
	* We tell the kernel to initialize the Guest: this returns the open
	* /dev/lguest file descriptor.
	*/
	tell_kernel(start);		tell_kernel(start);

	/* Ensure that we terminate if a device-servicing child dies. */		/* Ensure that we terminate if a device-servicing child dies. */

arch/x86/include/asm/lguest_hcall.h

+1 −0

Original line number	Original line	Diff line number	Diff line
	@@ -61,6 +61,7 @@ hcall(unsigned long call,
	: "memory");		: "memory");
	return call;		return call;
	}		}
			/:/

	/* Can't use our min() macro here: needs to be a constant */		/* Can't use our min() macro here: needs to be a constant */
	#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)		#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)

arch/x86/kernel/asm-offsets_32.c

+0 −1

Original line number	Original line	Diff line number	Diff line
	@@ -63,7 +63,6 @@ void foo(void)
	BLANK();		BLANK();
	OFFSET(LGUEST_DATA_irq_enabled, lguest_data, irq_enabled);		OFFSET(LGUEST_DATA_irq_enabled, lguest_data, irq_enabled);
	OFFSET(LGUEST_DATA_irq_pending, lguest_data, irq_pending);		OFFSET(LGUEST_DATA_irq_pending, lguest_data, irq_pending);
	OFFSET(LGUEST_DATA_pgdir, lguest_data, pgdir);

	BLANK();		BLANK();
	OFFSET(LGUEST_PAGES_host_gdt_desc, lguest_pages, state.host_gdt_desc);		OFFSET(LGUEST_PAGES_host_gdt_desc, lguest_pages, state.host_gdt_desc);

arch/x86/lguest/boot.c

+22 −14

Original line number	Original line	Diff line number	Diff line
	@@ -71,7 +71,8 @@
	#include <asm/stackprotector.h>		#include <asm/stackprotector.h>
	#include <asm/reboot.h> /* for struct machine_ops */		#include <asm/reboot.h> /* for struct machine_ops */

	/*G:010 Welcome to the Guest!		/*G:010
			* Welcome to the Guest!
	*		*
	* The Guest in our tale is a simple creature: identical to the Host but		* The Guest in our tale is a simple creature: identical to the Host but
	* behaving in simplified but equivalent ways. In particular, the Guest is the		* behaving in simplified but equivalent ways. In particular, the Guest is the
	@@ -190,15 +191,23 @@ static void lazy_hcall4(unsigned long call,
	#endif		#endif

	/*G:036		/*G:036
	* When lazy mode is turned off reset the per-cpu lazy mode variable and then		* When lazy mode is turned off, we issue the do-nothing hypercall to
	* issue the do-nothing hypercall to flush any stored calls.		* flush any stored calls, and call the generic helper to reset the
	:*/		* per-cpu lazy mode variable.
			*/
	static void lguest_leave_lazy_mmu_mode(void)		static void lguest_leave_lazy_mmu_mode(void)
	{		{
	hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0);		hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0);
	paravirt_leave_lazy_mmu();		paravirt_leave_lazy_mmu();
	}		}

			/*
			* We also catch the end of context switch; we enter lazy mode for much of
			* that too, so again we need to flush here.
			*
			* (Technically, this is lazy CPU mode, and normally we're in lazy MMU
			* mode, but unlike Xen, lguest doesn't care about the difference).
			*/
	static void lguest_end_context_switch(struct task_struct *next)		static void lguest_end_context_switch(struct task_struct *next)
	{		{
	hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0);		hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0);
	@@ -391,7 +400,7 @@ static void lguest_load_tr_desc(void)
	* giant ball of hair. Its entry in the current Intel manual runs to 28 pages.		* giant ball of hair. Its entry in the current Intel manual runs to 28 pages.
	*		*
	* This instruction even it has its own Wikipedia entry. The Wikipedia entry		* This instruction even it has its own Wikipedia entry. The Wikipedia entry
	* has been translated into 5 languages. I am not making this up!		* has been translated into 6 languages. I am not making this up!
	*		*
	* We could get funky here and identify ourselves as "GenuineLguest", but		* We could get funky here and identify ourselves as "GenuineLguest", but
	* instead we just use the real "cpuid" instruction. Then I pretty much turned		* instead we just use the real "cpuid" instruction. Then I pretty much turned
	@@ -458,7 +467,7 @@ static void lguest_cpuid(unsigned int ax, unsigned int bx,
	/*		/*
	* PAE systems can mark pages as non-executable. Linux calls this the		* PAE systems can mark pages as non-executable. Linux calls this the
	* NX bit. Intel calls it XD (eXecute Disable), AMD EVP (Enhanced		* NX bit. Intel calls it XD (eXecute Disable), AMD EVP (Enhanced
	* Virus Protection). We just switch turn if off here, since we don't		* Virus Protection). We just switch it off here, since we don't
	* support it.		* support it.
	*/		*/
	case 0x80000001:		case 0x80000001:
	@@ -520,17 +529,16 @@ static unsigned long lguest_read_cr2(void)

	/* See lguest_set_pte() below. */		/* See lguest_set_pte() below. */
	static bool cr3_changed = false;		static bool cr3_changed = false;
			static unsigned long current_cr3;

	/*		/*
	* cr3 is the current toplevel pagetable page: the principle is the same as		* cr3 is the current toplevel pagetable page: the principle is the same as
	* cr0. Keep a local copy, and tell the Host when it changes. The only		* cr0. Keep a local copy, and tell the Host when it changes.
	* difference is that our local copy is in lguest_data because the Host needs
	* to set it upon our initial hypercall.
	*/		*/
	static void lguest_write_cr3(unsigned long cr3)		static void lguest_write_cr3(unsigned long cr3)
	{		{
	lguest_data.pgdir = cr3;
	lazy_hcall1(LHCALL_NEW_PGTABLE, cr3);		lazy_hcall1(LHCALL_NEW_PGTABLE, cr3);
			current_cr3 = cr3;

	/* These two page tables are simple, linear, and used during boot */		/* These two page tables are simple, linear, and used during boot */
	if (cr3 != __pa(swapper_pg_dir) && cr3 != __pa(initial_page_table))		if (cr3 != __pa(swapper_pg_dir) && cr3 != __pa(initial_page_table))
	@@ -539,7 +547,7 @@ static void lguest_write_cr3(unsigned long cr3)

	static unsigned long lguest_read_cr3(void)		static unsigned long lguest_read_cr3(void)
	{		{
	return lguest_data.pgdir;		return current_cr3;
	}		}

	/* cr4 is used to enable and disable PGE, but we don't care. */		/* cr4 is used to enable and disable PGE, but we don't care. */
	@@ -758,7 +766,7 @@ static void lguest_pmd_clear(pmd_t *pmdp)
	static void lguest_flush_tlb_single(unsigned long addr)		static void lguest_flush_tlb_single(unsigned long addr)
	{		{
	/* Simply set it to zero: if it was not, it will fault back in. */		/* Simply set it to zero: if it was not, it will fault back in. */
	lazy_hcall3(LHCALL_SET_PTE, lguest_data.pgdir, addr, 0);		lazy_hcall3(LHCALL_SET_PTE, current_cr3, addr, 0);
	}		}

	/*		/*

arch/x86/lguest/i386_head.S

+20 −15

Original line number	Original line	Diff line number	Diff line
	@@ -6,18 +6,22 @@
	#include <asm/processor-flags.h>		#include <asm/processor-flags.h>

	/*G:020		/*G:020
	* Our story starts with the kernel booting into startup_32 in
	* arch/x86/kernel/head_32.S. It expects a boot header, which is created by		* Our story starts with the bzImage: booting starts at startup_32 in
	* the bootloader (the Launcher in our case).		* arch/x86/boot/compressed/head_32.S. This merely uncompresses the real
			* kernel in place and then jumps into it: startup_32 in
			* arch/x86/kernel/head_32.S. Both routines expects a boot header in the %esi
			* register, which is created by the bootloader (the Launcher in our case).
	*		*
	* The startup_32 function does very little: it clears the uninitialized global		* The startup_32 function does very little: it clears the uninitialized global
	* C variables which we expect to be zero (ie. BSS) and then copies the boot		* C variables which we expect to be zero (ie. BSS) and then copies the boot
	* header and kernel command line somewhere safe. Finally it checks the		* header and kernel command line somewhere safe, and populates some initial
	* 'hardware_subarch' field. This was introduced in 2.6.24 for lguest and Xen:		* page tables. Finally it checks the 'hardware_subarch' field. This was
	* if it's set to '1' (lguest's assigned number), then it calls us here.		* introduced in 2.6.24 for lguest and Xen: if it's set to '1' (lguest's
			* assigned number), then it calls us here.
	*		*
	* WARNING: be very careful here! We're running at addresses equal to physical		* WARNING: be very careful here! We're running at addresses equal to physical
	* addesses (around 0), not above PAGE_OFFSET as most code expectes		* addresses (around 0), not above PAGE_OFFSET as most code expects
	* (eg. 0xC0000000). Jumps are relative, so they're OK, but we can't touch any		* (eg. 0xC0000000). Jumps are relative, so they're OK, but we can't touch any
	* data without remembering to subtract __PAGE_OFFSET!		* data without remembering to subtract __PAGE_OFFSET!
	*		*
	@@ -27,13 +31,18 @@
	.section .init.text, "ax", @progbits		.section .init.text, "ax", @progbits
	ENTRY(lguest_entry)		ENTRY(lguest_entry)
	/*		/*
	* We make the "initialization" hypercall now to tell the Host about		* We make the "initialization" hypercall now to tell the Host where
	* us, and also find out where it put our page tables.		* our lguest_data struct is.
	*/		*/
	movl $LHCALL_LGUEST_INIT, %eax		movl $LHCALL_LGUEST_INIT, %eax
	movl $lguest_data - __PAGE_OFFSET, %ebx		movl $lguest_data - __PAGE_OFFSET, %ebx
	int $LGUEST_TRAP_ENTRY		int $LGUEST_TRAP_ENTRY

			/* Now turn our pagetables on; setup by arch/x86/kernel/head_32.S. */
			movl $LHCALL_NEW_PGTABLE, %eax
			movl $(initial_page_table - __PAGE_OFFSET), %ebx
			int $LGUEST_TRAP_ENTRY

	/* Set up the initial stack so we can run C code. */		/* Set up the initial stack so we can run C code. */
	movl $(init_thread_union+THREAD_SIZE),%esp		movl $(init_thread_union+THREAD_SIZE),%esp

	@@ -96,12 +105,8 @@ send_interrupts:
	*/		*/
	pushl %eax		pushl %eax
	movl $LHCALL_SEND_INTERRUPTS, %eax		movl $LHCALL_SEND_INTERRUPTS, %eax
	/*		/* This is the actual hypercall trap. */
	* This is a vmcall instruction (same thing that KVM uses). Older		int $LGUEST_TRAP_ENTRY
	* assembler versions might not know the "vmcall" instruction, so we
	* create one manually here.
	*/
	.byte 0x0f,0x01,0xc1 /* KVM_HYPERCALL */
	/* Put eax back the way we found it. */		/* Put eax back the way we found it. */
	popl %eax		popl %eax
	ret		ret