[patch] remove hugetlb syscalls

[patch] remove hugetlb syscalls

[Benjamin LaHaise]

Hello,

Since the functionality of the hugetlb syscalls is now available via 
hugetlbfs with better control over permissions, could you apply the 
following patch that gets rid of a lot of duplicate and unnescessary 
code by removing the two hugetlb syscalls?  This patch was only tested 
on x86, so if people could take a look over it and see if I missed 
anything I'd appreciate it.  Thanks,

		-ben
-- 
"Do you seek knowledge in time travel?"


 arch/i386/kernel/entry.S         |    4 
 arch/i386/kernel/sys_i386.c      |   67 -----------
 arch/i386/mm/hugetlbpage.c       |  218 ---------------------------------------
 arch/ia64/kernel/entry.S         |    4 
 arch/ia64/kernel/sys_ia64.c      |   75 -------------
 arch/ia64/mm/hugetlbpage.c       |  199 -----------------------------------
 arch/sparc64/kernel/sys_sparc.c  |   97 -----------------
 arch/sparc64/kernel/systbls.S    |    4 
 include/asm-alpha/unistd.h       |    2 
 include/asm-i386/unistd.h        |    2 
 include/asm-ia64/unistd.h        |    2 
 include/asm-ppc/unistd.h         |    2 
 include/asm-ppc64/unistd.h       |    2 
 include/asm-sparc/unistd.h       |    2 
 include/asm-sparc64/unistd.h     |    2 
 include/asm-x86_64/ia32_unistd.h |    2 
 17 files changed, 6 insertions(+), 678 deletions(-)

:r v2.5.47-mm2-hugetlbcleanup.diff
diff -urN v2.5.47-mm2/arch/i386/kernel/entry.S v2.5.47-mm2-hugetlbcleanup/arch/i386/kernel/entry.S
--- v2.5.47-mm2/arch/i386/kernel/entry.S	Wed Nov 13 18:12:15 2002
+++ v2.5.47-mm2-hugetlbcleanup/arch/i386/kernel/entry.S	Wed Nov 13 18:17:05 2002
@@ -760,8 +760,8 @@
 	.long sys_io_getevents
 	.long sys_io_submit
 	.long sys_io_cancel
-	.long sys_alloc_hugepages /* 250 */
-	.long sys_free_hugepages
+	.long sys_ni_syscall	/* 250 */
+	.long sys_ni_syscall
 	.long sys_exit_group
 	.long sys_lookup_dcookie
 	.long sys_epoll_create
diff -urN v2.5.47-mm2/arch/i386/kernel/sys_i386.c v2.5.47-mm2-hugetlbcleanup/arch/i386/kernel/sys_i386.c
--- v2.5.47-mm2/arch/i386/kernel/sys_i386.c	Wed Nov 13 18:09:55 2002
+++ v2.5.47-mm2-hugetlbcleanup/arch/i386/kernel/sys_i386.c	Wed Nov 13 18:21:24 2002
@@ -9,7 +9,6 @@
 #include <linux/errno.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
-#include <linux/hugetlb.h>
 #include <linux/smp.h>
 #include <linux/smp_lock.h>
 #include <linux/sem.h>
@@ -248,69 +247,3 @@
 	return error;
 }
 
-#ifdef CONFIG_HUGETLB_PAGE
-/* get_addr function gets the currently unused virtaul range in
- * current process's address space.  It returns the HPAGE_SIZE
- * aligned address (in cases of success).  Other kernel generic
- * routines only could gurantee that allocated address is PAGE_SIZE aligned.
- */
-static unsigned long get_addr(unsigned long addr, unsigned long len)
-{
-	struct vm_area_struct *vma;
-	if (addr) {
-		addr = (addr + HPAGE_SIZE - 1) & HPAGE_MASK;
-		vma = find_vma(current->mm, addr);
-		if (TASK_SIZE > addr + len && !(vma && addr + len >= vma->vm_start))
-			goto found_addr;
-	}
-	addr = TASK_UNMAPPED_BASE;
-	for (vma = find_vma(current->mm, addr); TASK_SIZE > addr + len; vma = vma->vm_next) {
-		if (!vma || addr + len < vma->vm_start)
-			goto found_addr;
-		addr = (vma->vm_end + HPAGE_SIZE - 1) & HPAGE_MASK;
-	}
-	return -ENOMEM;
-found_addr:
-	return addr;
-}
-
-asmlinkage unsigned long sys_alloc_hugepages(int key, unsigned long addr, unsigned long len, int prot, int flag)
-{
-	struct mm_struct *mm = current->mm;
-	unsigned long   raddr;
-	int     retval = 0;
-	extern int alloc_hugetlb_pages(int, unsigned long, unsigned long, int, int);
-	if (!cpu_has_pse || key < 0 || len & ~HPAGE_MASK)
-		return -EINVAL;
-	down_write(&mm->mmap_sem);
-	raddr = get_addr(addr, len);
-	if (raddr != -ENOMEM)
-		retval = alloc_hugetlb_pages(key, raddr, len, prot, flag);
-	up_write(&mm->mmap_sem);
-	return (retval < 0) ? (unsigned long)retval : raddr;
-}
-
-asmlinkage int sys_free_hugepages(unsigned long addr)
-{
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	int retval;
-
-	vma = find_vma(current->mm, addr);
-	if (!vma || !(vma->vm_flags & VM_HUGETLB) || vma->vm_start != addr)
-		return -EINVAL;
-	down_write(&mm->mmap_sem);
-	retval = do_munmap(vma->vm_mm, addr, vma->vm_end - addr);
-	up_write(&mm->mmap_sem);
-	return retval;
-}
-#else
-asmlinkage unsigned long sys_alloc_hugepages(int key, unsigned long addr, size_t len, int prot, int flag)
-{
-	return -ENOSYS;
-}
-asmlinkage int sys_free_hugepages(unsigned long addr)
-{
-	return -ENOSYS;
-}
-#endif
diff -urN v2.5.47-mm2/arch/i386/mm/hugetlbpage.c v2.5.47-mm2-hugetlbcleanup/arch/i386/mm/hugetlbpage.c
--- v2.5.47-mm2/arch/i386/mm/hugetlbpage.c	Wed Nov 13 18:10:01 2002
+++ v2.5.47-mm2-hugetlbcleanup/arch/i386/mm/hugetlbpage.c	Wed Nov 13 18:33:51 2002
@@ -32,17 +32,6 @@
 	int key;
 } htlbpagek[MAX_ID];
 
-static struct inode *find_key_inode(int key)
-{
-	int i;
-
-	for (i = 0; i < MAX_ID; i++) {
-		if (htlbpagek[i].key == key)
-			return (htlbpagek[i].in);
-	}
-	return NULL;
-}
-
 static struct page *alloc_hugetlb_page(void)
 {
 	int i;
@@ -101,57 +90,6 @@
 	set_pte(page_table, entry);
 }
 
-static int anon_get_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, int write_access, pte_t *page_table)
-{
-	struct page *page = alloc_hugetlb_page();
-	if (page)
-		set_huge_pte(mm, vma, page, page_table, write_access);
-	return page ? 1 : -1;
-}
-
-static int make_hugetlb_pages_present(unsigned long addr, unsigned long end, int flags)
-{
-	int write;
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	pte_t *pte;
-
-	vma = find_vma(mm, addr);
-	if (!vma)
-		goto out_error1;
-
-	write = (vma->vm_flags & VM_WRITE) != 0;
-	if ((vma->vm_end - vma->vm_start) & (HPAGE_SIZE - 1))
-		goto out_error1;
-	spin_lock(&mm->page_table_lock);
-	do {
-		pte = huge_pte_alloc(mm, addr);
-		if ((pte) && (pte_none(*pte))) {
-			if (anon_get_hugetlb_page(mm, vma,
-					   write ? VM_WRITE : VM_READ,
-					   pte) == -1)
-				goto out_error;
-		} else
-			goto out_error;
-		addr += HPAGE_SIZE;
-	} while (addr < end);
-	spin_unlock(&mm->page_table_lock);
-	vma->vm_flags |= (VM_HUGETLB | VM_RESERVED);
-	if (flags & MAP_PRIVATE)
-		vma->vm_flags |= VM_DONTCOPY;
-	vma->vm_ops = &hugetlb_vm_ops;
-	return 0;
-out_error:		/* Error case, remove the partial lp_resources. */
-	if (addr > vma->vm_start) {
-		vma->vm_end = addr;
-		zap_hugepage_range(vma, vma->vm_start, vma->vm_end - vma->vm_start);
-		vma->vm_end = end;
-	}
-	spin_unlock(&mm->page_table_lock);
-      out_error1:
-	return -1;
-}
-
 int
 copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
 			struct vm_area_struct *vma)
@@ -297,138 +235,6 @@
 	spin_unlock(&mm->page_table_lock);
 }
 
-static struct inode *set_new_inode(unsigned long len, int prot, int flag, int key)
-{
-	struct inode *inode;
-	int i;
-
-	for (i = 0; i < MAX_ID; i++) {
-		if (htlbpagek[i].key == 0)
-			break;
-	}
-	if (i == MAX_ID)
-		return NULL;
-	inode = kmalloc(sizeof (struct inode), GFP_ATOMIC);
-	if (inode == NULL)
-		return NULL;
-
-	inode_init_once(inode);
-	atomic_inc(&inode->i_writecount);
-	inode->i_mapping = &inode->i_data;
-	inode->i_mapping->host = inode;
-	inode->i_ino = (unsigned long)key;
-
-	htlbpagek[i].key = key;
-	htlbpagek[i].in = inode;
-	inode->i_uid = current->fsuid;
-	inode->i_gid = current->fsgid;
-	inode->i_mode = prot;
-	inode->i_size = len;
-	return inode;
-}
-
-static int check_size_prot(struct inode *inode, unsigned long len, int prot, int flag)
-{
-	if (inode->i_uid != current->fsuid)
-		return -1;
-	if (inode->i_gid != current->fsgid)
-		return -1;
-	if (inode->i_size != len)
-		return -1;
-	return 0;
-}
-
-static int alloc_shared_hugetlb_pages(int key, unsigned long addr, unsigned long len, int prot, int flag)
-{
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	struct inode *inode;
-	struct address_space *mapping;
-	int idx;
-	int retval = -ENOMEM;
-	int newalloc = 0;
-
-try_again:
-	spin_lock(&htlbpage_lock);
-
-	inode = find_key_inode(key);
-	if (inode == NULL) {
-		if (!capable(CAP_SYS_ADMIN)) {
-			if (!in_group_p(0)) {
-				retval = -EPERM;
-				goto out_err;
-			}
-		}
-		if (!(flag & IPC_CREAT)) {
-			retval = -ENOENT;
-			goto out_err;
-		}
-		inode = set_new_inode(len, prot, flag, key);
-		if (inode == NULL)
-			goto out_err;
-		newalloc = 1;
-	} else {
-		if (check_size_prot(inode, len, prot, flag) < 0) {
-			retval = -EINVAL;
-			goto out_err;
-		}
-		else if (atomic_read(&inode->i_writecount)) {
-			spin_unlock(&htlbpage_lock);
-			goto try_again;
-		}
-	}
-	spin_unlock(&htlbpage_lock);
-	mapping = inode->i_mapping;
-
-	addr = do_mmap_pgoff(NULL, addr, len, (unsigned long) prot,
-			MAP_NORESERVE|MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, 0);
-	if (IS_ERR((void *) addr))
-		goto freeinode;
-
-	vma = find_vma(mm, addr);
-	if (!vma) {
-		retval = -EINVAL;
-		goto freeinode;
-	}
-
-	retval = hugetlb_prefault(mapping, vma);
-	if (retval)
-		goto out;
-
-	vma->vm_flags |= (VM_HUGETLB | VM_RESERVED);
-	vma->vm_ops = &hugetlb_vm_ops;
-	spin_unlock(&mm->page_table_lock);
-	spin_lock(&htlbpage_lock);
-	atomic_set(&inode->i_writecount, 0);
-	spin_unlock(&htlbpage_lock);
-	return retval;
-out:
-	if (addr > vma->vm_start) {
-		unsigned long raddr;
-		raddr = vma->vm_end;
-		vma->vm_end = addr;
-		zap_hugepage_range(vma, vma->vm_start, vma->vm_end - vma->vm_start);
-		vma->vm_end = raddr;
-	}
-	spin_unlock(&mm->page_table_lock);
-	do_munmap(mm, vma->vm_start, len);
-	if (newalloc)
-		goto freeinode;
-	return retval;
-out_err: spin_unlock(&htlbpage_lock);
-freeinode:
-	 if (newalloc) {
-		 for(idx=0;idx<MAX_ID;idx++)
-			 if (htlbpagek[idx].key == inode->i_ino) {
-				 htlbpagek[idx].key = 0;
-				 htlbpagek[idx].in = NULL;
-				 break;
-			 }
-		 kfree(inode);
-	 }
-	 return retval;
-}
-
 int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
 {
 	struct mm_struct *mm = current->mm;
@@ -470,30 +276,6 @@
 	return ret;
 }
 
-static int alloc_private_hugetlb_pages(int key, unsigned long addr, unsigned long len, int prot, int flag)
-{
-	if (!capable(CAP_SYS_ADMIN)) {
-		if (!in_group_p(0))
-			return -EPERM;
-	}
-	addr = do_mmap_pgoff(NULL, addr, len, prot,
-			MAP_NORESERVE|MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, 0);
-	if (IS_ERR((void *) addr))
-		return -ENOMEM;
-	if (make_hugetlb_pages_present(addr, (addr + len), flag) < 0) {
-		do_munmap(current->mm, addr, len);
-		return -ENOMEM;
-	}
-	return 0;
-}
-
-int alloc_hugetlb_pages(int key, unsigned long addr, unsigned long len, int prot, int flag)
-{
-	if (key > 0)
-		return alloc_shared_hugetlb_pages(key, addr, len, prot, flag);
-	return alloc_private_hugetlb_pages(key, addr, len, prot, flag);
-}
-
 int set_hugetlb_mem_size(int count)
 {
 	int j, lcount;
diff -urN v2.5.47-mm2/arch/ia64/kernel/entry.S v2.5.47-mm2-hugetlbcleanup/arch/ia64/kernel/entry.S
--- v2.5.47-mm2/arch/ia64/kernel/entry.S	Wed Nov 13 18:09:55 2002
+++ v2.5.47-mm2-hugetlbcleanup/arch/ia64/kernel/entry.S	Wed Nov 13 18:27:58 2002
@@ -1242,8 +1242,8 @@
 	data8 sys_sched_setaffinity
 	data8 sys_sched_getaffinity
 	data8 sys_security
-	data8 sys_alloc_hugepages
-	data8 sys_free_hugepages		// 1235
+	data8 ia64_ni_syscall
+	data8 ia64_ni_syscall		// 1235
 	data8 sys_exit_group
 	data8 sys_lookup_dcookie
 	data8 sys_io_setup
diff -urN v2.5.47-mm2/arch/ia64/kernel/sys_ia64.c v2.5.47-mm2-hugetlbcleanup/arch/ia64/kernel/sys_ia64.c
--- v2.5.47-mm2/arch/ia64/kernel/sys_ia64.c	Wed Nov 13 18:09:55 2002
+++ v2.5.47-mm2-hugetlbcleanup/arch/ia64/kernel/sys_ia64.c	Wed Nov 13 18:20:33 2002
@@ -9,7 +9,6 @@
 #include <linux/errno.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
-#include <linux/hugetlb.h>
 #include <linux/mman.h>
 #include <linux/sched.h>
 #include <linux/file.h>		/* doh, must come after sched.h... */
@@ -243,80 +242,6 @@
 	return addr;
 }
 
-#ifdef CONFIG_HUGETLB_PAGE
-
-asmlinkage unsigned long
-sys_alloc_hugepages (int key, unsigned long addr, size_t len, int prot, int flag)
-{
-	struct mm_struct *mm = current->mm;
-	long retval;
-	extern int alloc_hugetlb_pages (int, unsigned long, unsigned long, int, int);
-
-	if ((key < 0) || (len & (HPAGE_SIZE - 1)))
-		return -EINVAL;
-
-	if (addr && ((REGION_NUMBER(addr) != REGION_HPAGE) || (addr & (HPAGE_SIZE - 1))))
-		addr = TASK_HPAGE_BASE;
-
-	if (!addr)
-		addr = TASK_HPAGE_BASE;
-	down_write(&mm->mmap_sem);
-	{
-		retval = arch_get_unmapped_area(NULL, COLOR_HALIGN(addr), len, 0, 0);
-		if (retval != -ENOMEM)
-			retval = alloc_hugetlb_pages(key, retval, len, prot, flag);
-	}
-	up_write(&mm->mmap_sem);
-
-	if (IS_ERR((void *) retval))
-		return retval;
-
-	force_successful_syscall_return();
-	return retval;
-}
-
-asmlinkage int
-sys_free_hugepages (unsigned long  addr)
-{
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	extern int free_hugepages(struct vm_area_struct *);
-	int retval;
-
-	down_write(&mm->mmap_sem);
-	{
-		vma = find_vma(mm, addr);
-		if (!vma || !is_vm_hugetlb_page(vma) || (vma->vm_start != addr))
-			retval = -EINVAL;
-			goto out;
-
-		spin_lock(&mm->page_table_lock);
-		{
-			retval = free_hugepages(vma);
-		}
-		spin_unlock(&mm->page_table_lock);
-	}
-out:
-	up_write(&mm->mmap_sem);
-	return retval;
-}
-
-#else /* !CONFIG_HUGETLB_PAGE */
-
-asmlinkage unsigned long
-sys_alloc_hugepages (int key, size_t addr, unsigned long len, int prot, int flag)
-{
-	return -ENOSYS;
-}
-
-asmlinkage unsigned long
-sys_free_hugepages (unsigned long  addr)
-{
-	return -ENOSYS;
-}
-
-#endif /* !CONFIG_HUGETLB_PAGE */
-
 asmlinkage long
 sys_vm86 (long arg0, long arg1, long arg2, long arg3)
 {
diff -urN v2.5.47-mm2/arch/ia64/mm/hugetlbpage.c v2.5.47-mm2-hugetlbcleanup/arch/ia64/mm/hugetlbpage.c
--- v2.5.47-mm2/arch/ia64/mm/hugetlbpage.c	Wed Nov 13 18:09:55 2002
+++ v2.5.47-mm2-hugetlbcleanup/arch/ia64/mm/hugetlbpage.c	Wed Nov 13 18:40:11 2002
@@ -31,18 +31,6 @@
 	int key;
 } htlbpagek[MAX_ID];
 
-static struct inode *
-find_key_inode(int key)
-{
-	int i;
-
-	for (i = 0; i < MAX_ID; i++) {
-		if (htlbpagek[i].key == key)
-			return (htlbpagek[i].in);
-	}
-	return NULL;
-}
-
 static struct page *
 alloc_hugetlb_page (void)
 {
@@ -305,193 +293,6 @@
 }
 
 int
-free_hugepages (struct vm_area_struct *mpnt)
-{
-	unlink_vma(mpnt);
-	zap_hugetlb_resources(mpnt);
-	kmem_cache_free(vm_area_cachep, mpnt);
-	return 1;
-}
-
-static struct inode *
-set_new_inode (unsigned long len, int prot, int flag, int key)
-{
-	struct inode *inode;
-	int i;
-
-	for (i = 0; i < MAX_ID; i++) {
-		if (htlbpagek[i].key == 0)
-			break;
-	}
-	if (i == MAX_ID)
-		return NULL;
-	inode = kmalloc(sizeof (struct inode), GFP_ATOMIC);
-	if (inode == NULL)
-		return NULL;
-
-	inode_init_once(inode);
-	atomic_inc(&inode->i_writecount);
-	inode->i_mapping = &inode->i_data;
-	inode->i_mapping->host = inode;
-	inode->i_ino = (unsigned long) key;
-
-	htlbpagek[i].key = key;
-	htlbpagek[i].in = inode;
-	inode->i_uid = current->fsuid;
-	inode->i_gid = current->fsgid;
-	inode->i_mode = prot;
-	inode->i_size = len;
-	return inode;
-}
-
-static int
-check_size_prot (struct inode *inode, unsigned long len, int prot, int flag)
-{
-	if (inode->i_uid != current->fsuid)
-		return -1;
-	if (inode->i_gid != current->fsgid)
-		return -1;
-	if (inode->i_size != len)
-		return -1;
-	return 0;
-}
-
-int
-alloc_shared_hugetlb_pages (int key, unsigned long addr, unsigned long len, int prot, int flag)
-{
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	struct inode *inode;
-	struct address_space *mapping;
-	struct page *page;
-	int idx;
-	int retval = -ENOMEM;
-	int newalloc = 0;
-
-try_again:
-	spin_lock(&htlbpage_lock);
-	inode = find_key_inode(key);
-	if (inode == NULL) {
-		if (!capable(CAP_SYS_ADMIN)) {
-			if (!in_group_p(0)) {
-				retval = -EPERM;
-				goto out_err;
-			}
-		}
-		if (!(flag & IPC_CREAT)) {
-			retval = -ENOENT;
-			goto out_err;
-		}
-		inode = set_new_inode(len, prot, flag, key);
-		if (inode == NULL)
-			goto out_err;
-		newalloc = 1;
-	} else {
-		if (check_size_prot(inode, len, prot, flag) < 0) {
-			retval =  -EINVAL;
-			goto out_err;
-		}
-		else if (atomic_read(&inode->i_writecount)) {
-			spin_unlock(&htlbpage_lock);
-			goto try_again;
-		}
-	}
-	spin_unlock(&htlbpage_lock);
-	mapping = inode->i_mapping;
-
-	addr = do_mmap_pgoff(NULL, addr, len, (unsigned long) prot,
-			     MAP_NORESERVE|MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, 0);
-	if (IS_ERR((void *) addr))
-		goto freeinode;
-
-	vma = find_vma(mm, addr);
-	if (!vma) {
-		retval = -EINVAL;
-		goto freeinode;
-	}
-
-	spin_lock(&mm->page_table_lock);
-	do {
-		pte_t *pte = huge_pte_alloc(mm, addr);
-		if ((pte) && (pte_none(*pte))) {
-			idx = (addr - vma->vm_start) >> HPAGE_SHIFT;
-			page = find_get_page(mapping, idx);
-			if (page == NULL) {
-				page = alloc_hugetlb_page();
-				if (page == NULL)
-					goto out;
-				add_to_page_cache(page, mapping, idx);
-			}
-			set_huge_pte(mm, vma, page, pte,
-				     (vma->vm_flags & VM_WRITE));
-		} else
-			goto out;
-		addr += HPAGE_SIZE;
-	} while (addr < vma->vm_end);
-	retval = 0;
-	vma->vm_flags |= (VM_HUGETLB | VM_RESERVED);
-	vma->vm_ops = &hugetlb_vm_ops;
-	spin_unlock(&mm->page_table_lock);
-	spin_lock(&htlbpage_lock);
-	atomic_set(&inode->i_writecount, 0);
-	spin_unlock(&htlbpage_lock);
-	return retval;
-out:
-	if (addr > vma->vm_start) {
-		unsigned long raddr = vma->vm_end;
-		vma->vm_end = addr;
-		zap_hugetlb_resources(vma);
-		vma->vm_end = raddr;
-	}
-	spin_unlock(&mm->page_table_lock);
-	do_munmap(mm, vma->vm_start, len);
-	if (newalloc)
-		goto freeinode;
-	return retval;
-
-out_err:
-	spin_unlock(&htlbpage_lock);
-freeinode:
-	if (newalloc) {
-		for (idx = 0; idx < MAX_ID; idx++)
-			if (htlbpagek[idx].key == inode->i_ino) {
-				htlbpagek[idx].key = 0;
-				htlbpagek[idx].in = NULL;
-				break;
-			}
-		kfree(inode);
-	}
-	return retval;
-}
-
-static int
-alloc_private_hugetlb_pages (int key, unsigned long addr, unsigned long len, int prot, int flag)
-{
-	if (!capable(CAP_SYS_ADMIN)) {
-		if (!in_group_p(0))
-			return -EPERM;
-	}
-	addr = do_mmap_pgoff(NULL, addr, len, prot,
-			     MAP_NORESERVE | MAP_PRIVATE | MAP_FIXED | MAP_ANONYMOUS, 0);
-	if (IS_ERR((void *) addr))
-		return -ENOMEM;
-	if (make_hugetlb_pages_present(addr, (addr + len), flag) < 0) {
-		do_munmap(current->mm, addr, len);
-		return -ENOMEM;
-	}
-	return 0;
-}
-
-int
-alloc_hugetlb_pages (int key, unsigned long addr, unsigned long len, int prot, int flag)
-{
-	if (key > 0)
-		return alloc_shared_hugetlb_pages(key, addr, len, prot, flag);
-	else
-		return alloc_private_hugetlb_pages(key, addr, len, prot, flag);
-}
-
-int
 set_hugetlb_mem_size (int count)
 {
 	int j, lcount;
diff -urN v2.5.47-mm2/arch/sparc64/kernel/sys_sparc.c v2.5.47-mm2-hugetlbcleanup/arch/sparc64/kernel/sys_sparc.c
--- v2.5.47-mm2/arch/sparc64/kernel/sys_sparc.c	Wed Nov 13 18:09:56 2002
+++ v2.5.47-mm2-hugetlbcleanup/arch/sparc64/kernel/sys_sparc.c	Wed Nov 13 18:21:12 2002
@@ -13,7 +13,6 @@
 #include <linux/fs.h>
 #include <linux/file.h>
 #include <linux/mm.h>
-#include <linux/hugetlb.h>
 #include <linux/sem.h>
 #include <linux/msg.h>
 #include <linux/shm.h>
@@ -683,99 +682,3 @@
 	return err;
 }
 
-#ifdef CONFIG_HUGETLB_PAGE
-#define HPAGE_ALIGN(x)  (((unsigned long)x + (HPAGE_SIZE -1)) & HPAGE_MASK)
-extern long     sys_munmap(unsigned long, size_t);
-
-/* get_addr function gets the currently unused virtual range in
- * the current process's address space.  It returns the LARGE_PAGE_SIZE
- * aligned address (in cases of success).  Other kernel generic
- * routines only could gurantee that allocated address is PAGE_SIZE aligned.
- */
-static long get_addr(unsigned long addr, unsigned long len)
-{
-	struct vm_area_struct   *vma;
-	if (addr) {
-		addr = HPAGE_ALIGN(addr);
-		vma = find_vma(current->mm, addr);
-		if (((TASK_SIZE - len) >= addr) &&
-				(!vma || addr + len <= vma->vm_start))
-			goto found_addr;
-	}
-	addr = HPAGE_ALIGN(TASK_UNMAPPED_BASE);
-	for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) {
-		if (TASK_SIZE - len < addr)
-			return -ENOMEM;
-		if (!vma || ((addr + len) < vma->vm_start))
-			goto found_addr;
-		addr = vma->vm_end;
-	}
-found_addr:
-	addr = HPAGE_ALIGN(addr);
-	return addr;
-}
-
-extern int alloc_hugetlb_pages(int, unsigned long, unsigned long, int, int);
-
-asmlinkage long
-sys_alloc_hugepages(int key, unsigned long addr, unsigned long len, int prot, int flag)
-{
-	struct mm_struct *mm = current->mm;
-	unsigned long raddr;
-	int retval;
-
-	if (key < 0)
-		return -EINVAL;
-	if (len & (HPAGE_SIZE - 1))
-		return -EINVAL;
-	down_write(&mm->mmap_sem);
-	raddr = get_addr(addr, len);
-	retval = 0;
-	if (raddr == -ENOMEM) {
-		retval = -ENOMEM;
-		goto raddr_out;
-	}
-	retval = alloc_hugetlb_pages(key, raddr, len, prot, flag);
-
-raddr_out:
-	up_write(&mm->mmap_sem);
-	if (retval < 0)
-		return (long) retval;
-
-	return raddr;
-}
-
-extern int free_hugepages(struct vm_area_struct *);
-
-asmlinkage int
-sys_free_hugepages(unsigned long addr)
-{
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	int retval;
-
-	vma = find_vma(current->mm, addr);
-	if ((!vma) || (!is_vm_hugetlb_page(vma)) || (vma->vm_start!=addr))
-		return -EINVAL;
-	down_write(&mm->mmap_sem);
-	spin_lock(&mm->page_table_lock);
-	retval = free_hugepages(vma);
-	spin_unlock(&mm->page_table_lock);
-	up_write(&mm->mmap_sem);
-	return retval;
-}
-
-#else
-
-asmlinkage long
-sys_alloc_hugepages(int key, unsigned long addr, size_t len, int prot, int flag)
-{
-	return -ENOSYS;
-}
-asmlinkage int
-sys_free_hugepages(unsigned long addr)
-{
-	return -ENOSYS;
-}
-
-#endif
diff -urN v2.5.47-mm2/arch/sparc64/kernel/systbls.S v2.5.47-mm2-hugetlbcleanup/arch/sparc64/kernel/systbls.S
--- v2.5.47-mm2/arch/sparc64/kernel/systbls.S	Wed Nov 13 18:12:16 2002
+++ v2.5.47-mm2-hugetlbcleanup/arch/sparc64/kernel/systbls.S	Wed Nov 13 18:27:21 2002
@@ -65,8 +65,8 @@
 	.word sys32_ipc, sys32_sigreturn, sys_clone, sys_nis_syscall, sys32_adjtimex
 /*220*/	.word sys32_sigprocmask, sys_ni_syscall, sys32_delete_module, sys_ni_syscall, sys_getpgid
 	.word sys32_bdflush, sys32_sysfs, sys_nis_syscall, sys32_setfsuid16, sys32_setfsgid16
-/*230*/	.word sys32_select, sys_time, sys_nis_syscall, sys_stime, sys_alloc_hugepages
-	.word sys_free_hugepages, sys_llseek, sys_mlock, sys_munlock, sys_mlockall
+/*230*/	.word sys32_select, sys_time, sys_nis_syscall, sys_stime, sys_ni_syscall
+	.word sys_ni_syscall, sys_llseek, sys_mlock, sys_munlock, sys_mlockall
 /*240*/	.word sys_munlockall, sys_sched_setparam, sys_sched_getparam, sys_sched_setscheduler, sys_sched_getscheduler
 	.word sys_sched_yield, sys_sched_get_priority_max, sys_sched_get_priority_min, sys32_sched_rr_get_interval, sys32_nanosleep
 /*250*/	.word sys32_mremap, sys32_sysctl, sys_getsid, sys_fdatasync, sys32_nfsservctl
diff -urN v2.5.47-mm2/include/asm-alpha/unistd.h v2.5.47-mm2-hugetlbcleanup/include/asm-alpha/unistd.h
--- v2.5.47-mm2/include/asm-alpha/unistd.h	Wed Nov 13 18:09:58 2002
+++ v2.5.47-mm2-hugetlbcleanup/include/asm-alpha/unistd.h	Wed Nov 13 18:23:03 2002
@@ -340,8 +340,6 @@
 #define __NR_io_getevents		400
 #define __NR_io_submit			401
 #define __NR_io_cancel			402
-#define __NR_alloc_hugepages		403
-#define __NR_free_hugepages		404
 #define __NR_exit_group			405
 #define NR_SYSCALLS			406
 
diff -urN v2.5.47-mm2/include/asm-i386/unistd.h v2.5.47-mm2-hugetlbcleanup/include/asm-i386/unistd.h
--- v2.5.47-mm2/include/asm-i386/unistd.h	Wed Nov 13 18:09:58 2002
+++ v2.5.47-mm2-hugetlbcleanup/include/asm-i386/unistd.h	Wed Nov 13 18:22:04 2002
@@ -254,8 +254,6 @@
 #define __NR_io_getevents	247
 #define __NR_io_submit		248
 #define __NR_io_cancel		249
-#define __NR_alloc_hugepages	250
-#define __NR_free_hugepages	251
 #define __NR_exit_group		252
 #define __NR_lookup_dcookie	253
 #define __NR_sys_epoll_create	254
diff -urN v2.5.47-mm2/include/asm-ia64/unistd.h v2.5.47-mm2-hugetlbcleanup/include/asm-ia64/unistd.h
--- v2.5.47-mm2/include/asm-ia64/unistd.h	Wed Nov 13 18:09:58 2002
+++ v2.5.47-mm2-hugetlbcleanup/include/asm-ia64/unistd.h	Wed Nov 13 18:24:20 2002
@@ -223,8 +223,6 @@
 #define __NR_sched_setaffinity		1231
 #define __NR_sched_getaffinity		1232
 #define __NR_security			1233
-#define __NR_alloc_hugepages		1234
-#define __NR_free_hugepages		1235
 #define __NR_exit_group			1236
 #define __NR_lookup_dcookie		1237
 #define __NR_io_setup			1238
diff -urN v2.5.47-mm2/include/asm-ppc/unistd.h v2.5.47-mm2-hugetlbcleanup/include/asm-ppc/unistd.h
--- v2.5.47-mm2/include/asm-ppc/unistd.h	Wed Nov 13 18:10:05 2002
+++ v2.5.47-mm2-hugetlbcleanup/include/asm-ppc/unistd.h	Wed Nov 13 18:24:03 2002
@@ -236,8 +236,6 @@
 #define __NR_io_getevents	229
 #define __NR_io_submit		230
 #define __NR_io_cancel		231
-#define __NR_alloc_hugepages	232
-#define __NR_free_hugepages	233
 #define __NR_exit_group		234
 #define __NR_lookup_dcookie	235
 #define __NR_sys_epoll_create	236
diff -urN v2.5.47-mm2/include/asm-ppc64/unistd.h v2.5.47-mm2-hugetlbcleanup/include/asm-ppc64/unistd.h
--- v2.5.47-mm2/include/asm-ppc64/unistd.h	Wed Nov 13 18:24:46 2002
+++ v2.5.47-mm2-hugetlbcleanup/include/asm-ppc64/unistd.h	Wed Nov 13 18:25:17 2002
@@ -241,8 +241,6 @@
 #define __NR_io_getevents	229
 #define __NR_io_submit		230
 #define __NR_io_cancel		231
-#define __NR_alloc_hugepages	232
-#define __NR_free_hugepages	233
 #define __NR_exit_group		234
 
 #define __NR(n)	#n
diff -urN v2.5.47-mm2/include/asm-sparc/unistd.h v2.5.47-mm2-hugetlbcleanup/include/asm-sparc/unistd.h
--- v2.5.47-mm2/include/asm-sparc/unistd.h	Wed Nov 13 18:10:05 2002
+++ v2.5.47-mm2-hugetlbcleanup/include/asm-sparc/unistd.h	Wed Nov 13 18:23:27 2002
@@ -249,8 +249,6 @@
 #define __NR_time               231 /* Linux Specific                              */
 /* #define __NR_oldstat         232    Linux Specific                              */
 #define __NR_stime              233 /* Linux Specific                              */
-#define __NR_alloc_hugepages    234 /* Linux Specific                              */
-#define __NR_free_hugepages     235 /* Linux Specific                              */
 #define __NR__llseek            236 /* Linux Specific                              */
 #define __NR_mlock              237
 #define __NR_munlock            238
diff -urN v2.5.47-mm2/include/asm-sparc64/unistd.h v2.5.47-mm2-hugetlbcleanup/include/asm-sparc64/unistd.h
--- v2.5.47-mm2/include/asm-sparc64/unistd.h	Wed Nov 13 18:10:05 2002
+++ v2.5.47-mm2-hugetlbcleanup/include/asm-sparc64/unistd.h	Wed Nov 13 18:23:42 2002
@@ -251,8 +251,6 @@
 #endif
 /* #define __NR_oldstat         232    Linux Specific                              */
 #define __NR_stime              233 /* Linux Specific                              */
-#define __NR_alloc_hugepages    234 /* Linux Specific                              */
-#define __NR_free_hugepages     235 /* Linux Specific                              */
 #define __NR__llseek            236 /* Linux Specific                              */
 #define __NR_mlock              237
 #define __NR_munlock            238
diff -urN v2.5.47-mm2/include/asm-x86_64/ia32_unistd.h v2.5.47-mm2-hugetlbcleanup/include/asm-x86_64/ia32_unistd.h
--- v2.5.47-mm2/include/asm-x86_64/ia32_unistd.h	Mon Nov  4 16:15:14 2002
+++ v2.5.47-mm2-hugetlbcleanup/include/asm-x86_64/ia32_unistd.h	Wed Nov 13 18:26:03 2002
@@ -256,8 +256,6 @@
 #define __NR_ia32_io_getevents	247
 #define __NR_ia32_io_submit		248
 #define __NR_ia32_io_cancel		249
-#define __NR_ia32_alloc_hugepages		250
-#define __NR_ia32_free_hugepages		251
 #define __NR_ia32_exit_group		252
 
 #define IA32_NR_syscalls 260	/* must be > than biggest syscall! */	
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Re: [patch] remove hugetlb syscalls

[Rik van Riel]

On Wed, 13 Nov 2002, Benjamin LaHaise wrote:

> Since the functionality of the hugetlb syscalls is now available via
> hugetlbfs with better control over permissions, could you apply the
> following patch that gets rid of a lot of duplicate and unnescessary
> code by removing the two hugetlb syscalls?

#include <massive_applause.h>

Yes, lets get rid of this ugliness before somebody actually
finds a way to use these syscalls...

regards,

Rik
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Re: [patch] remove hugetlb syscalls

[dada1]

I beg to differ.

I already use the syscalls.

The patch doesnt change Documentation/vm/hugetlbpage.txt

How one is supposed to use hugetlbfs ? That's not documented.

Before dropping support for syscalls, please change the Documentation.

Thanks

----- Original Message -----
From: "Rik van Riel" <riel@conectiva.com.br>
To: "Benjamin LaHaise" <bcrl@redhat.com>
Cc: "Andrew Morton" <akpm@digeo.com>; <linux-mm@kvack.org>;
<linux-kernel@vger.kernel.org>
Sent: Thursday, November 14, 2002 1:42 AM
Subject: Re: [patch] remove hugetlb syscalls


> On Wed, 13 Nov 2002, Benjamin LaHaise wrote:
>
> > Since the functionality of the hugetlb syscalls is now available via
> > hugetlbfs with better control over permissions, could you apply the
> > following patch that gets rid of a lot of duplicate and unnescessary
> > code by removing the two hugetlb syscalls?
>
> #include <massive_applause.h>
>
> Yes, lets get rid of this ugliness before somebody actually
> finds a way to use these syscalls...
>
> regards,
>
> Rik
> --
> Bravely reimplemented by the knights who say "NIH".
> http://www.surriel.com/ http://guru.conectiva.com/
> Current spamtrap:  <a
href=mailto:"october@surriel.com">october@surriel.com</a>
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
>

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Re: [patch] remove hugetlb syscalls

[Christoph Hellwig]

On Thu, Nov 14, 2002 at 09:52:33AM +0100, dada1 wrote:
> I beg to differ.
> 
> I already use the syscalls.

For what?

> How one is supposed to use hugetlbfs ? That's not documented.

mount -t hugetlbfs whocares /huge

fd = open("/huge/nose", ..)

mmap(.., fd, ..)

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Re: [patch] remove hugetlb syscalls

[dada1]

Thanks Christoph

If I asked, this is because I tried the obvious and it doesnt work.

# cat /proc/version
Linux version 2.5.47 (root@whatever.com) (gcc version 3.2) #10 Tue Nov 12
11:27:43 CET 2002
# cat /proc/sys/vm/nr_hugepages
4
# cat /proc/meminfo | grep Huge
HugePages_Total:     4
HugePages_Free:      4
Hugepagesize:     4096 kB
# mount | grep huge
whocares on /huge type hugetlbfs (rw)
# cat huge.c
#include <unistd.h>
#include <asm/unistd.h>
#include <errno.h>
#include <stdio.h>
#include <sys/mman.h>

#ifndef __NR_sys_alloc_hugepages
# define __NR_sys_alloc_hugepages 250
#endif

#define BIGSZ (4*1024*1024)

_syscall5(void *, sys_alloc_hugepages, int, key, unsigned long, addr,
size_t, len, int, prot, int, flag)

main(argc, argv)
int argc ;
char  *argv[] ;
{
char *ptr ;
int c ;
int fd = -1 ;
int nbp = 1 ;
while ((c = getopt(argc, argv, "n:f:")) != EOF) {
    switch (c) {
        case 'n':
            nbp = atoi(optarg) ; break ;
        case 'f' :
            fd = open(optarg, 2) ; break ;
        }
    }
if (fd != -1) {
    ftruncate(fd, nbp*BIGSZ) ;
    ptr = mmap(0, nbp*BIGSZ, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0) ;
        if (ptr == (char *)-1)
                ptr = mmap(0, nbp*BIGSZ, PROT_READ|PROT_WRITE, MAP_PRIVATE,
fd, 0) ;
    }
else
    ptr = sys_alloc_hugepages(0, 0, nbp*BIGSZ, PROT_READ|PROT_WRITE, 0) ;

printf("alloc %d 4Mo pages ptr=%p errno=%d\n", nbp, ptr, errno) ;

pause() ;
}

# ./huge   # (using the syscall)
alloc 1 4Mo pages ptr=0x40400000 errno=0
^C
# ls -l /huge/BIG
-rw-r--r--    1 root     root      4194304 Nov 14 15:57 /huge/BIG
# ./huge -f /huge/BIG  (using mmap)
./huge -f /huge/BIG
alloc 1 4Mo pages ptr=0xffffffff errno=22
^C
# strace ...
open("/huge/BIG", O_RDWR)               = 3
ftruncate(3, 4194304)                   = 0
mmap2(NULL, 4194304, PROT_READ|PROT_WRITE, MAP_SHARED, 3, 0) = -1 EINVAL
(Invalid argument)
mmap2(NULL, 4194304, PROT_READ|PROT_WRITE, MAP_PRIVATE, 3, 0) = -1 EINVAL
(Invalid argument)


Not a trivial task it seems. The syscall is very easy.. sorry.

Thanks


From: "Christoph Hellwig" <hch@infradead.org>
> On Thu, Nov 14, 2002 at 09:52:33AM +0100, dada1 wrote:
> > I beg to differ.
> >
> > I already use the syscalls.
>
> For what?
>
> > How one is supposed to use hugetlbfs ? That's not documented.
>
> mount -t hugetlbfs whocares /huge
>
> fd = open("/huge/nose", ..)
>
> mmap(.., fd, ..)
>

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Re: [patch] remove hugetlb syscalls

[Benjamin LaHaise]

On Thu, Nov 14, 2002 at 04:13:56PM +0100, dada1 wrote:
> Thanks Christoph
> 
> If I asked, this is because I tried the obvious and it doesnt work.

It's a file.  You need to use MAP_SHARED.

		-ben
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Re: [patch] remove hugetlb syscalls

[dada1]

Please look again into my mail :)

 ptr = mmap(0, nbp*BIGSZ, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0) ;
        if (ptr == (char *)-1)
                ptr = mmap(0, nbp*BIGSZ, PROT_READ|PROT_WRITE, MAP_PRIVATE,
fd, 0);

mmap2(NULL, 4194304, PROT_READ|PROT_WRITE, MAP_SHARED, 3, 0) = -1 EINVAL

mmap2(NULL, 4194304, PROT_READ|PROT_WRITE, MAP_PRIVATE, 3, 0) = -1 EINVAL

I tried the two versions. MAP_SHARED and MAP_PRIVATE



From: "Benjamin LaHaise" <bcrl@redhat.com>
> On Thu, Nov 14, 2002 at 04:13:56PM +0100, dada1 wrote:
> > Thanks Christoph
> >
> > If I asked, this is because I tried the obvious and it doesnt work.
>
> It's a file.  You need to use MAP_SHARED.
>
> -ben
>

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Re: [patch] remove hugetlb syscalls

[Benjamin LaHaise]

On Thu, Nov 14, 2002 at 11:51:46AM -0800, Rohit Seth wrote:
> [-- text/html is unsupported (use 'v' to view this part) --]

Sorry, but your html-only email got trapped by the spam filters 
of linux-mm and linux-kernel.

		-ben
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Re: [patch] remove hugetlb syscalls

[Benjamin LaHaise]

On Thu, Nov 14, 2002 at 11:51:46AM -0800, Rohit Seth wrote:
> [-- text/html is unsupported (use 'v' to view this part) --]

Sorry, but your html-only email got trapped by the spam filters 
of linux-mm and linux-kernel.

		-ben
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Re: [patch] remove hugetlb syscalls

[Rohit Seth]

Benjamin LaHaise wrote:

>On Thu, Nov 14, 2002 at 04:13:56PM +0100, dada1 wrote:
>  
>
>>Thanks Christoph
>>
>>If I asked, this is because I tried the obvious and it doesnt work.
>>    
>>
>
>It's a file.  You need to use MAP_SHARED.
>  
>
This is not the problem with MAP_SHARED.  It is the lack of  (arch 
specific) hugepage aligned function support in the kernel. You can use 
the mmap on hugetlbfs using only MAP_FIXED with properly aligned 
addresses (but then this also is only a hint to kernel).  With addr == 
 NULL in mmap, the function is bound to fail almost all the times.


Thanks Ben for letting me know the problem with previous post.

>  
>



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Re: [patch] remove hugetlb syscalls

[William Lee Irwin III]

On Thu, Nov 14, 2002 at 12:11:32PM -0800, Rohit Seth wrote:
> This is not the problem with MAP_SHARED.  It is the lack of  (arch 
> specific) hugepage aligned function support in the kernel. You can use 
> the mmap on hugetlbfs using only MAP_FIXED with properly aligned 
> addresses (but then this also is only a hint to kernel).  With addr == 
> NULL in mmap, the function is bound to fail almost all the times.

There's very little standing in the way of automatic placement. If in
your opinion it should be implemented, I'll add that feature today.

IIRC you mentioned you would like to export the arch-specific
hugepage-aligned vma placement functions; once these are available,
it should be trivial to reuse them.


Thanks,
Bill
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Re: [patch] remove hugetlb syscalls

[William Lee Irwin III]

On Wed, Nov 13, 2002 at 06:45:55PM -0500, Benjamin LaHaise wrote:
> Since the functionality of the hugetlb syscalls is now available via 
> hugetlbfs with better control over permissions, could you apply the 
> following patch that gets rid of a lot of duplicate and unnescessary 
> code by removing the two hugetlb syscalls?  This patch was only tested 
> on x86, so if people could take a look over it and see if I missed 
> anything I'd appreciate it.  Thanks,

The main reason I haven't considered doing this is because they already
got in and there appears to be a user (Oracle/IA64).

My strategy has been instead to contribute fixes, cleanups, and some
redesign of internal data structure management so that the code is more
palatable and robust in general. And I think this process has gone well
enough to say that the system calls are relatively inoffensive, or will
be once what's in various patch queues as of today hits mainline.

Basically, I myself don't have a user of the stuff I need to service,
but I already know who's going to scream if it hits the chopping block.

The primary motivation behind the funding of hugetlbfs was to export
the superpage functionality as a tmpfs-like filesystem to other
in-kernel facilities, most notably SysV shm, for interoperability with
other databases (DB2) that are very insistent about utilizing superpages
in combination with SysV shm. Some additional benefits are available,
though not utilized, because the files may be larger than the virtual
address space on i386, and so mmap()-based windowing into a large
virtual arena could reap both TLB and space consumption benefits, which
benefit is also desired for (eventual) database usage, and is already
very beneficial to simpler applications with high concurrency levels
operating on shared memory arenas backed by it..

Oracle itself prefers to perform scatter/gather mappings at a
granularity too small for hugetlb on i386, and so sys_remap_file_pages()
is its preferred solution.

There are various oddities here. sys_remap_file_pages() is a new
syscall, hugetlbfs is a RAM-backed filesystem that supports only mmap()
and truncate(), and only on specifically-aligned regions. But IMHO with
effort and careful design, these facilities have either been cleanly
implemented or made clean once re-examined, and so supporting databases
has in the end not damaged the integrity or cleanliness of the generic VM.


Bill
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Re: [patch] remove hugetlb syscalls

[Benjamin LaHaise]

On Thu, Nov 14, 2002 at 12:30:35PM -0800, William Lee Irwin III wrote:
> The main reason I haven't considered doing this is because they already
> got in and there appears to be a user (Oracle/IA64).

Not in shipping code.  Certainly no vendor kernels that I am aware of 
have shipped these syscalls yet either, as nearly all of the developers 
find them revolting.  Not to mention that the code cleanups and bugfixes 
are still ongoing.

		-ben
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Re: [patch] remove hugetlb syscalls

[William Lee Irwin III]

On Thu, Nov 14, 2002 at 12:30:35PM -0800, William Lee Irwin III wrote:
>> The main reason I haven't considered doing this is because they already
>> got in and there appears to be a user (Oracle/IA64).

On Thu, Nov 14, 2002 at 03:48:09PM -0500, Benjamin LaHaise wrote:
> Not in shipping code.  Certainly no vendor kernels that I am aware of 
> have shipped these syscalls yet either, as nearly all of the developers 
> find them revolting.  Not to mention that the code cleanups and bugfixes 
> are still ongoing.

This is a bit out of my hands; the support decision came from elsewhere.
I have to service my users first, and after that, I don't generally want
to stand in the way of others. In general it's good to have minimalistic
interfaces, but I'm not a party to the concerns regarding the syscalls.
My direct involvement there has been either of a kernel janitor nature,
helping to adapt it to Linux kernel idioms, or reusing code for hugetlbfs.

I guess the only real statement left to make is that hugetlbfs (or my
participation/implementation of it) was not originally intended to
compete with the syscalls, though there's a lot of obvious overlap
(which I tried to exploit by means of code reuse).

Bill
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Re: [patch] remove hugetlb syscalls

[Benjamin LaHaise]

Oracle does not run as root, so they can't even use the syscalls 
directly.  At least with hugetlbfs we can chmod the filesystem to be 
owned by the oracle user.

		-ben

On Thu, Nov 14, 2002 at 01:02:20PM -0800, William Lee Irwin III wrote:
> On Thu, Nov 14, 2002 at 12:30:35PM -0800, William Lee Irwin III wrote:
> >> The main reason I haven't considered doing this is because they already
> >> got in and there appears to be a user (Oracle/IA64).
> 
> On Thu, Nov 14, 2002 at 03:48:09PM -0500, Benjamin LaHaise wrote:
> > Not in shipping code.  Certainly no vendor kernels that I am aware of 
> > have shipped these syscalls yet either, as nearly all of the developers 
> > find them revolting.  Not to mention that the code cleanups and bugfixes 
> > are still ongoing.
> 
> This is a bit out of my hands; the support decision came from elsewhere.
> I have to service my users first, and after that, I don't generally want
> to stand in the way of others. In general it's good to have minimalistic
> interfaces, but I'm not a party to the concerns regarding the syscalls.
> My direct involvement there has been either of a kernel janitor nature,
> helping to adapt it to Linux kernel idioms, or reusing code for hugetlbfs.
> 
> I guess the only real statement left to make is that hugetlbfs (or my
> participation/implementation of it) was not originally intended to
> compete with the syscalls, though there's a lot of obvious overlap
> (which I tried to exploit by means of code reuse).
> 
> Bill

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Re: [patch] remove hugetlb syscalls

[William Lee Irwin III]

On Thu, Nov 14, 2002 at 04:11:34PM -0500, Benjamin LaHaise wrote:
> Oracle does not run as root, so they can't even use the syscalls 
> directly.  At least with hugetlbfs we can chmod the filesystem to be 
> owned by the oracle user.

Okay, the advantage with respect to permissions is clear; now there is
a correction to the permissions checking I should do, as CAP_IPC_LOCK
is currently checked in ->f_ops->mmap(), but the permissions are
enforcible by means of ordinary vfs permissions, and so it's redundant.


Bill
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Re: [patch] remove hugetlb syscalls

[Rohit Seth]

Benjamin LaHaise wrote:

>Oracle does not run as root, so they can't even use the syscalls 
>directly.  At least with hugetlbfs we can chmod the filesystem to be 
>owned by the oracle user.
>
>		-ben
>
>  
>
Strictly speaking user don't have to be root.  Currently the syscall 
only requires users to have root as one of the supplementary groups (and 
that is how Oracle is actually using these syscalls).  And if 
CAP_IPC_LOCK (to make it coherent with fs side of the world) is what is 
preferdto provide access to hugepages then that change is simple also. 
 Don't need to do any chmod.

rohit


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Re: [patch] remove hugetlb syscalls

[Benjamin LaHaise]

On Thu, Nov 14, 2002 at 01:40:25PM -0800, Rohit Seth wrote:
> Strictly speaking user don't have to be root.  Currently the syscall 
> only requires users to have root as one of the supplementary groups (and 
> that is how Oracle is actually using these syscalls).  And if 
> CAP_IPC_LOCK (to make it coherent with fs side of the world) is what is 
> preferdto provide access to hugepages then that change is simple also. 
>  Don't need to do any chmod.

Chmod is easier to administor (the special permissions are obvious with 
a standard tool called ls), and doesn't require giving random apps root 
privs (good practice still dictates that database backends should not 
have root).  Capabilities would work, but have yet to catch on in any 
real sense and are lacking in terms of useful tools in most distributions.

		-ben
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Re: [patch] remove hugetlb syscalls

[Benjamin LaHaise]

On Thu, Nov 14, 2002 at 12:30:35PM -0800, William Lee Irwin III wrote:
> The main reason I haven't considered doing this is because they already
> got in and there appears to be a user (Oracle/IA64).

Not in shipping code.  Certainly no vendor kernels that I am aware of 
have shipped these syscalls yet either, as nearly all of the developers 
find them revolting.  Not to mention that the code cleanups and bugfixes 
are still ongoing.

		-ben
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Re: [patch] remove hugetlb syscalls

[Benjamin LaHaise]

On Thu, Nov 14, 2002 at 12:30:35PM -0800, William Lee Irwin III wrote:
> The main reason I haven't considered doing this is because they already
> got in and there appears to be a user (Oracle/IA64).

Not in shipping code.  Certainly no vendor kernels that I am aware of 
have shipped these syscalls yet either, as nearly all of the developers 
find them revolting.  Not to mention that the code cleanups and bugfixes 
are still ongoing.

		-ben
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RE: [patch] remove hugetlb syscalls

[Seth, Rohit]

> -----Original Message-----
> From: William Lee Irwin III [mailto:wli@holomorphy.com] 
> > 
> On Thu, Nov 14, 2002 at 12:11:32PM -0800, Rohit Seth wrote:
> > This is not the problem with MAP_SHARED.  It is the lack of  (arch
> > specific) hugepage aligned function support in the kernel. 
> You can use 
> > the mmap on hugetlbfs using only MAP_FIXED with properly aligned 
> > addresses (but then this also is only a hint to kernel).  
> With addr == 
> > NULL in mmap, the function is bound to fail almost all the times.
> 
> There's very little standing in the way of automatic 
> placement. If in your opinion it should be implemented, I'll 
> add that feature today.
> 
mmap with addr==NULL is in my opinion a very useful thing.

> IIRC you mentioned you would like to export the arch-specific 
> hugepage-aligned vma placement functions; once these are 
> available, it should be trivial to reuse them.
> 
> 
I will export those functions from arch specific trees.
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