diff options
Diffstat (limited to 'arch/um/sys-i386/ldt.c')
| -rw-r--r-- | arch/um/sys-i386/ldt.c | 215 | 
1 files changed, 104 insertions, 111 deletions
diff --git a/arch/um/sys-i386/ldt.c b/arch/um/sys-i386/ldt.c index 906c2a4e727..0bf7572a80a 100644 --- a/arch/um/sys-i386/ldt.c +++ b/arch/um/sys-i386/ldt.c @@ -1,34 +1,26 @@  /* - * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com) + * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)   * Licensed under the GPL   */ -#include "linux/sched.h" -#include "linux/slab.h" -#include "linux/types.h" -#include "linux/errno.h" -#include "linux/spinlock.h" -#include "asm/uaccess.h" -#include "asm/smp.h" -#include "asm/ldt.h" +#include "linux/mm.h"  #include "asm/unistd.h" -#include "kern.h"  #include "os.h" - -extern int modify_ldt(int func, void *ptr, unsigned long bytecount); - +#include "proc_mm.h"  #include "skas.h"  #include "skas_ptrace.h" -#include "asm/mmu_context.h" -#include "proc_mm.h" +#include "sysdep/tls.h" + +extern int modify_ldt(int func, void *ptr, unsigned long bytecount);  long write_ldt_entry(struct mm_id * mm_idp, int func, struct user_desc * desc,  		     void **addr, int done)  {  	long res; -	if(proc_mm){ -		/* This is a special handling for the case, that the mm to +	if (proc_mm) { +		/* +		 * This is a special handling for the case, that the mm to  		 * modify isn't current->active_mm.  		 * If this is called directly by modify_ldt,  		 *     (current->active_mm->context.skas.u == mm_idp) @@ -40,12 +32,12 @@ long write_ldt_entry(struct mm_id * mm_idp, int func, struct user_desc * desc,  		 *  		 * Note: I'm unsure: should interrupts be disabled here?  		 */ -		if(!current->active_mm || current->active_mm == &init_mm || -		   mm_idp != ¤t->active_mm->context.skas.id) +		if (!current->active_mm || current->active_mm == &init_mm || +		    mm_idp != ¤t->active_mm->context.skas.id)  			__switch_mm(mm_idp);  	} -	if(ptrace_ldt) { +	if (ptrace_ldt) {  		struct ptrace_ldt ldt_op = (struct ptrace_ldt) {  			.func = func,  			.ptr = desc, @@ -53,7 +45,7 @@ long write_ldt_entry(struct mm_id * mm_idp, int func, struct user_desc * desc,  		u32 cpu;  		int pid; -		if(!proc_mm) +		if (!proc_mm)  			pid = mm_idp->u.pid;  		else {  			cpu = get_cpu(); @@ -62,7 +54,7 @@ long write_ldt_entry(struct mm_id * mm_idp, int func, struct user_desc * desc,  		res = os_ptrace_ldt(pid, 0, (unsigned long) &ldt_op); -		if(proc_mm) +		if (proc_mm)  			put_cpu();  	}  	else { @@ -71,7 +63,7 @@ long write_ldt_entry(struct mm_id * mm_idp, int func, struct user_desc * desc,  					(sizeof(*desc) + sizeof(long) - 1) &  					    ~(sizeof(long) - 1),  					addr, &stub_addr); -		if(!res){ +		if (!res) {  			unsigned long args[] = { func,  						 (unsigned long)stub_addr,  						 sizeof(*desc), @@ -81,12 +73,13 @@ long write_ldt_entry(struct mm_id * mm_idp, int func, struct user_desc * desc,  		}  	} -	if(proc_mm){ -		/* This is the second part of special handling, that makes +	if (proc_mm) { +		/* +		 * This is the second part of special handling, that makes  		 * PTRACE_LDT possible to implement.  		 */ -		if(current->active_mm && current->active_mm != &init_mm && -		   mm_idp != ¤t->active_mm->context.skas.id) +		if (current->active_mm && current->active_mm != &init_mm && +		    mm_idp != ¤t->active_mm->context.skas.id)  			__switch_mm(¤t->active_mm->context.skas.id);  	} @@ -102,21 +95,22 @@ static long read_ldt_from_host(void __user * ptr, unsigned long bytecount)  			.ptr = kmalloc(bytecount, GFP_KERNEL)};  	u32 cpu; -	if(ptrace_ldt.ptr == NULL) +	if (ptrace_ldt.ptr == NULL)  		return -ENOMEM; -	/* This is called from sys_modify_ldt only, so userspace_pid gives +	/* +	 * This is called from sys_modify_ldt only, so userspace_pid gives  	 * us the right number  	 */  	cpu = get_cpu();  	res = os_ptrace_ldt(userspace_pid[cpu], 0, (unsigned long) &ptrace_ldt);  	put_cpu(); -	if(res < 0) +	if (res < 0)  		goto out;  	n = copy_to_user(ptr, ptrace_ldt.ptr, res); -	if(n != 0) +	if (n != 0)  		res = -EFAULT;    out: @@ -143,33 +137,32 @@ static int read_ldt(void __user * ptr, unsigned long bytecount)  	unsigned long size;  	uml_ldt_t * ldt = ¤t->mm->context.skas.ldt; -	if(!ldt->entry_count) +	if (!ldt->entry_count)  		goto out; -	if(bytecount > LDT_ENTRY_SIZE*LDT_ENTRIES) +	if (bytecount > LDT_ENTRY_SIZE*LDT_ENTRIES)  		bytecount = LDT_ENTRY_SIZE*LDT_ENTRIES;  	err = bytecount; -	if(ptrace_ldt){ +	if (ptrace_ldt)  		return read_ldt_from_host(ptr, bytecount); -	}  	down(&ldt->semaphore); -	if(ldt->entry_count <= LDT_DIRECT_ENTRIES){ +	if (ldt->entry_count <= LDT_DIRECT_ENTRIES) {  		size = LDT_ENTRY_SIZE*LDT_DIRECT_ENTRIES; -		if(size > bytecount) +		if (size > bytecount)  			size = bytecount; -		if(copy_to_user(ptr, ldt->u.entries, size)) +		if (copy_to_user(ptr, ldt->u.entries, size))  			err = -EFAULT;  		bytecount -= size;  		ptr += size;  	}  	else { -		for(i=0; i<ldt->entry_count/LDT_ENTRIES_PER_PAGE && bytecount; -			 i++){ +		for (i=0; i<ldt->entry_count/LDT_ENTRIES_PER_PAGE && bytecount; +		     i++) {  			size = PAGE_SIZE; -			if(size > bytecount) +			if (size > bytecount)  				size = bytecount; -			if(copy_to_user(ptr, ldt->u.pages[i], size)){ +			if (copy_to_user(ptr, ldt->u.pages[i], size)) {  				err = -EFAULT;  				break;  			} @@ -179,10 +172,10 @@ static int read_ldt(void __user * ptr, unsigned long bytecount)  	}  	up(&ldt->semaphore); -	if(bytecount == 0 || err == -EFAULT) +	if (bytecount == 0 || err == -EFAULT)  		goto out; -	if(clear_user(ptr, bytecount)) +	if (clear_user(ptr, bytecount))  		err = -EFAULT;  out: @@ -193,15 +186,16 @@ static int read_default_ldt(void __user * ptr, unsigned long bytecount)  {  	int err; -	if(bytecount > 5*LDT_ENTRY_SIZE) +	if (bytecount > 5*LDT_ENTRY_SIZE)  		bytecount = 5*LDT_ENTRY_SIZE;  	err = bytecount; -	/* UML doesn't support lcall7 and lcall27. +	/* +	 * UML doesn't support lcall7 and lcall27.  	 * So, we don't really have a default ldt, but emulate  	 * an empty ldt of common host default ldt size.  	 */ -	if(clear_user(ptr, bytecount)) +	if (clear_user(ptr, bytecount))  		err = -EFAULT;  	return err; @@ -217,52 +211,52 @@ static int write_ldt(void __user * ptr, unsigned long bytecount, int func)  	void *addr = NULL;  	err = -EINVAL; -	if(bytecount != sizeof(ldt_info)) +	if (bytecount != sizeof(ldt_info))  		goto out;  	err = -EFAULT; -	if(copy_from_user(&ldt_info, ptr, sizeof(ldt_info))) +	if (copy_from_user(&ldt_info, ptr, sizeof(ldt_info)))  		goto out;  	err = -EINVAL; -	if(ldt_info.entry_number >= LDT_ENTRIES) +	if (ldt_info.entry_number >= LDT_ENTRIES)  		goto out; -	if(ldt_info.contents == 3){ +	if (ldt_info.contents == 3) {  		if (func == 1)  			goto out;  		if (ldt_info.seg_not_present == 0)  			goto out;  	} -        if(!ptrace_ldt) -                down(&ldt->semaphore); +	if (!ptrace_ldt) +		down(&ldt->semaphore);  	err = write_ldt_entry(mm_idp, func, &ldt_info, &addr, 1); -	if(err) +	if (err)  		goto out_unlock; -        else if(ptrace_ldt) { -	/* With PTRACE_LDT available, this is used as a flag only */ -                ldt->entry_count = 1; -                goto out; -        } +	else if (ptrace_ldt) { +		/* With PTRACE_LDT available, this is used as a flag only */ +		ldt->entry_count = 1; +		goto out; +	} -	if(ldt_info.entry_number >= ldt->entry_count && -	   ldt_info.entry_number >= LDT_DIRECT_ENTRIES){ -		for(i=ldt->entry_count/LDT_ENTRIES_PER_PAGE; -		    i*LDT_ENTRIES_PER_PAGE <= ldt_info.entry_number; -		    i++){ -			if(i == 0) +	if (ldt_info.entry_number >= ldt->entry_count && +	    ldt_info.entry_number >= LDT_DIRECT_ENTRIES) { +		for (i=ldt->entry_count/LDT_ENTRIES_PER_PAGE; +		     i*LDT_ENTRIES_PER_PAGE <= ldt_info.entry_number; +		     i++) { +			if (i == 0)  				memcpy(&entry0, ldt->u.entries,  				       sizeof(entry0));  			ldt->u.pages[i] = (struct ldt_entry *)  				__get_free_page(GFP_KERNEL|__GFP_ZERO); -			if(!ldt->u.pages[i]){ +			if (!ldt->u.pages[i]) {  				err = -ENOMEM;  				/* Undo the change in host */  				memset(&ldt_info, 0, sizeof(ldt_info));  				write_ldt_entry(mm_idp, 1, &ldt_info, &addr, 1);  				goto out_unlock;  			} -			if(i == 0) { +			if (i == 0) {  				memcpy(ldt->u.pages[0], &entry0,  				       sizeof(entry0));  				memcpy(ldt->u.pages[0]+1, ldt->u.entries+1, @@ -271,17 +265,17 @@ static int write_ldt(void __user * ptr, unsigned long bytecount, int func)  			ldt->entry_count = (i + 1) * LDT_ENTRIES_PER_PAGE;  		}  	} -	if(ldt->entry_count <= ldt_info.entry_number) +	if (ldt->entry_count <= ldt_info.entry_number)  		ldt->entry_count = ldt_info.entry_number + 1; -	if(ldt->entry_count <= LDT_DIRECT_ENTRIES) +	if (ldt->entry_count <= LDT_DIRECT_ENTRIES)  		ldt_p = ldt->u.entries + ldt_info.entry_number;  	else  		ldt_p = ldt->u.pages[ldt_info.entry_number/LDT_ENTRIES_PER_PAGE] +  			ldt_info.entry_number%LDT_ENTRIES_PER_PAGE; -	if(ldt_info.base_addr == 0 && ldt_info.limit == 0 && -	   (func == 1 || LDT_empty(&ldt_info))){ +	if (ldt_info.base_addr == 0 && ldt_info.limit == 0 && +	   (func == 1 || LDT_empty(&ldt_info))) {  		ldt_p->a = 0;  		ldt_p->b = 0;  	} @@ -332,7 +326,7 @@ static void ldt_get_host_info(void)  	spin_lock(&host_ldt_lock); -	if(host_ldt_entries != NULL){ +	if (host_ldt_entries != NULL) {  		spin_unlock(&host_ldt_lock);  		return;  	} @@ -340,49 +334,49 @@ static void ldt_get_host_info(void)  	spin_unlock(&host_ldt_lock); -	for(i = LDT_PAGES_MAX-1, order=0; i; i>>=1, order++); +	for (i = LDT_PAGES_MAX-1, order=0; i; i>>=1, order++) +		;  	ldt = (struct ldt_entry *)  	      __get_free_pages(GFP_KERNEL|__GFP_ZERO, order); -	if(ldt == NULL) { -		printk("ldt_get_host_info: couldn't allocate buffer for host " -		       "ldt\n"); +	if (ldt == NULL) { +		printk(KERN_ERR "ldt_get_host_info: couldn't allocate buffer " +		       "for host ldt\n");  		return;  	}  	ret = modify_ldt(0, ldt, (1<<order)*PAGE_SIZE); -	if(ret < 0) { -		printk("ldt_get_host_info: couldn't read host ldt\n"); +	if (ret < 0) { +		printk(KERN_ERR "ldt_get_host_info: couldn't read host ldt\n");  		goto out_free;  	} -	if(ret == 0) { +	if (ret == 0) {  		/* default_ldt is active, simply write an empty entry 0 */  		host_ldt_entries = dummy_list;  		goto out_free;  	} -	for(i=0, size=0; i<ret/LDT_ENTRY_SIZE; i++){ -		if(ldt[i].a != 0 || ldt[i].b != 0) +	for (i=0, size=0; i<ret/LDT_ENTRY_SIZE; i++) { +		if (ldt[i].a != 0 || ldt[i].b != 0)  			size++;  	} -	if(size < ARRAY_SIZE(dummy_list)) +	if (size < ARRAY_SIZE(dummy_list))  		host_ldt_entries = dummy_list;  	else {  		size = (size + 1) * sizeof(dummy_list[0]);  		tmp = kmalloc(size, GFP_KERNEL); -		if(tmp == NULL) { -			printk("ldt_get_host_info: couldn't allocate host ldt " -			       "list\n"); +		if (tmp == NULL) { +			printk(KERN_ERR "ldt_get_host_info: couldn't allocate " +			       "host ldt list\n");  			goto out_free;  		}  		host_ldt_entries = tmp;  	} -	for(i=0, k=0; i<ret/LDT_ENTRY_SIZE; i++){ -		if(ldt[i].a != 0 || ldt[i].b != 0) { +	for (i=0, k=0; i<ret/LDT_ENTRY_SIZE; i++) { +		if (ldt[i].a != 0 || ldt[i].b != 0)  			host_ldt_entries[k++] = i; -		}  	}  	host_ldt_entries[k] = -1; @@ -401,15 +395,15 @@ long init_new_ldt(struct mmu_context_skas * new_mm,  	struct proc_mm_op copy; -	if(!ptrace_ldt) +	if (!ptrace_ldt)  		init_MUTEX(&new_mm->ldt.semaphore); -	if(!from_mm){ +	if (!from_mm) {  		memset(&desc, 0, sizeof(desc));  		/*  		 * We have to initialize a clean ldt.  		 */ -		if(proc_mm) { +		if (proc_mm) {  			/*  			 * If the new mm was created using proc_mm, host's  			 * default-ldt currently is assigned, which normally @@ -417,8 +411,7 @@ long init_new_ldt(struct mmu_context_skas * new_mm,  			 * To remove these gates, we simply write an empty  			 * entry as number 0 to the host.  			 */ -			err = write_ldt_entry(&new_mm->id, 1, &desc, -					      &addr, 1); +			err = write_ldt_entry(&new_mm->id, 1, &desc, &addr, 1);  		}  		else{  			/* @@ -427,11 +420,11 @@ long init_new_ldt(struct mmu_context_skas * new_mm,  			 * will be reset in the following loop  			 */  			ldt_get_host_info(); -			for(num_p=host_ldt_entries; *num_p != -1; num_p++){ +			for (num_p=host_ldt_entries; *num_p != -1; num_p++) {  				desc.entry_number = *num_p;  				err = write_ldt_entry(&new_mm->id, 1, &desc,  						      &addr, *(num_p + 1) == -1); -				if(err) +				if (err)  					break;  			}  		} @@ -440,8 +433,9 @@ long init_new_ldt(struct mmu_context_skas * new_mm,  		goto out;  	} -	if(proc_mm){ -		/* We have a valid from_mm, so we now have to copy the LDT of +	if (proc_mm) { +		/* +		 * We have a valid from_mm, so we now have to copy the LDT of  		 * from_mm to new_mm, because using proc_mm an new mm with  		 * an empty/default LDT was created in new_mm()  		 */ @@ -450,27 +444,27 @@ long init_new_ldt(struct mmu_context_skas * new_mm,  					      { .copy_segments =  							from_mm->id.u.mm_fd } } );  		i = os_write_file(new_mm->id.u.mm_fd, ©, sizeof(copy)); -		if(i != sizeof(copy)) -			printk("new_mm : /proc/mm copy_segments failed, " -			       "err = %d\n", -i); +		if (i != sizeof(copy)) +			printk(KERN_ERR "new_mm : /proc/mm copy_segments " +			       "failed, err = %d\n", -i);  	} -	if(!ptrace_ldt) { -		/* Our local LDT is used to supply the data for +	if (!ptrace_ldt) { +		/* +		 * Our local LDT is used to supply the data for  		 * modify_ldt(READLDT), if PTRACE_LDT isn't available,  		 * i.e., we have to use the stub for modify_ldt, which  		 * can't handle the big read buffer of up to 64kB.  		 */  		down(&from_mm->ldt.semaphore); -		if(from_mm->ldt.entry_count <= LDT_DIRECT_ENTRIES){ +		if (from_mm->ldt.entry_count <= LDT_DIRECT_ENTRIES)  			memcpy(new_mm->ldt.u.entries, from_mm->ldt.u.entries,  			       sizeof(new_mm->ldt.u.entries)); -		} -		else{ +		else {  			i = from_mm->ldt.entry_count / LDT_ENTRIES_PER_PAGE; -			while(i-->0){ +			while (i-->0) {  				page = __get_free_page(GFP_KERNEL|__GFP_ZERO); -				if (!page){ +				if (!page) {  					err = -ENOMEM;  					break;  				} @@ -493,11 +487,10 @@ void free_ldt(struct mmu_context_skas * mm)  {  	int i; -	if(!ptrace_ldt && mm->ldt.entry_count > LDT_DIRECT_ENTRIES){ +	if (!ptrace_ldt && mm->ldt.entry_count > LDT_DIRECT_ENTRIES) {  		i = mm->ldt.entry_count / LDT_ENTRIES_PER_PAGE; -		while(i-- > 0){ -			free_page((long )mm->ldt.u.pages[i]); -		} +		while (i-- > 0) +			free_page((long) mm->ldt.u.pages[i]);  	}  	mm->ldt.entry_count = 0;  }  |