Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 937 insertions, 0 deletions

diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c
new file mode 100644
index 000000000000..8d01dce8c532
--- /dev/null
+++ b/fs/xfs/xfs_acl.c
@@ -0,0 +1,937 @@
+/*
+ * Copyright (c) 2001-2002 Silicon Graphics, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include "xfs.h"
+
+#include "xfs_inum.h"
+#include "xfs_dir.h"
+#include "xfs_dir2.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_btree.h"
+#include "xfs_attr_sf.h"
+#include "xfs_dir_sf.h"
+#include "xfs_dir2_sf.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_acl.h"
+#include "xfs_mac.h"
+#include "xfs_attr.h"
+
+#include <linux/posix_acl_xattr.h>
+
+STATIC int      xfs_acl_setmode(vnode_t *, xfs_acl_t *, int *);
+STATIC void     xfs_acl_filter_mode(mode_t, xfs_acl_t *);
+STATIC void     xfs_acl_get_endian(xfs_acl_t *);
+STATIC int      xfs_acl_access(uid_t, gid_t, xfs_acl_t *, mode_t, cred_t *);
+STATIC int      xfs_acl_invalid(xfs_acl_t *);
+STATIC void     xfs_acl_sync_mode(mode_t, xfs_acl_t *);
+STATIC void     xfs_acl_get_attr(vnode_t *, xfs_acl_t *, int, int, int *);
+STATIC void     xfs_acl_set_attr(vnode_t *, xfs_acl_t *, int, int *);
+STATIC int      xfs_acl_allow_set(vnode_t *, int);
+
+kmem_zone_t *xfs_acl_zone;
+
+
+/*
+ * Test for existence of access ACL attribute as efficiently as possible.
+ */
+int
+xfs_acl_vhasacl_access(
+        vnode_t         *vp)
+{
+        int             error;
+
+        xfs_acl_get_attr(vp, NULL, _ACL_TYPE_ACCESS, ATTR_KERNOVAL, &error);
+        return (error == 0);
+}
+
+/*
+ * Test for existence of default ACL attribute as efficiently as possible.
+ */
+int
+xfs_acl_vhasacl_default(
+        vnode_t         *vp)
+{
+        int             error;
+
+        if (vp->v_type != VDIR)
+                return 0;
+        xfs_acl_get_attr(vp, NULL, _ACL_TYPE_DEFAULT, ATTR_KERNOVAL, &error);
+        return (error == 0);
+}
+
+/*
+ * Convert from extended attribute representation to in-memory for XFS.
+ */
+STATIC int
+posix_acl_xattr_to_xfs(
+        posix_acl_xattr_header  *src,
+        size_t                  size,
+        xfs_acl_t               *dest)
+{
+        posix_acl_xattr_entry   *src_entry;
+        xfs_acl_entry_t         *dest_entry;
+        int                     n;
+
+        if (!src || !dest)
+                return EINVAL;
+
+        if (size < sizeof(posix_acl_xattr_header))
+                return EINVAL;
+
+        if (src->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION))
+                return EOPNOTSUPP;
+
+        memset(dest, 0, sizeof(xfs_acl_t));
+        dest->acl_cnt = posix_acl_xattr_count(size);
+        if (dest->acl_cnt < 0 || dest->acl_cnt > XFS_ACL_MAX_ENTRIES)
+                return EINVAL;
+
+        /*
+         * acl_set_file(3) may request that we set default ACLs with
+         * zero length -- defend (gracefully) against that here.
+         */
+        if (!dest->acl_cnt)
+                return 0;
+
+        src_entry = (posix_acl_xattr_entry *)((char *)src + sizeof(*src));
+        dest_entry = &dest->acl_entry[0];
+
+        for (n = 0; n < dest->acl_cnt; n++, src_entry++, dest_entry++) {
+                dest_entry->ae_perm = le16_to_cpu(src_entry->e_perm);
+                if (_ACL_PERM_INVALID(dest_entry->ae_perm))
+                        return EINVAL;
+                dest_entry->ae_tag  = le16_to_cpu(src_entry->e_tag);
+                switch(dest_entry->ae_tag) {
+                case ACL_USER:
+                case ACL_GROUP:
+                        dest_entry->ae_id = le32_to_cpu(src_entry->e_id);
+                        break;
+                case ACL_USER_OBJ:
+                case ACL_GROUP_OBJ:
+                case ACL_MASK:
+                case ACL_OTHER:
+                        dest_entry->ae_id = ACL_UNDEFINED_ID;
+                        break;
+                default:
+                        return EINVAL;
+                }
+        }
+        if (xfs_acl_invalid(dest))
+                return EINVAL;
+
+        return 0;
+}
+
+/*
+ * Comparison function called from qsort().
+ * Primary key is ae_tag, secondary key is ae_id.
+ */
+STATIC int
+xfs_acl_entry_compare(
+        const void      *va,
+        const void      *vb)
+{
+        xfs_acl_entry_t *a = (xfs_acl_entry_t *)va,
+                        *b = (xfs_acl_entry_t *)vb;
+
+        if (a->ae_tag == b->ae_tag)
+                return (a->ae_id - b->ae_id);
+        return (a->ae_tag - b->ae_tag);
+}
+
+/*
+ * Convert from in-memory XFS to extended attribute representation.
+ */
+STATIC int
+posix_acl_xfs_to_xattr(
+        xfs_acl_t               *src,
+        posix_acl_xattr_header  *dest,
+        size_t                  size)
+{
+        int                     n;
+        size_t                  new_size = posix_acl_xattr_size(src->acl_cnt);
+        posix_acl_xattr_entry   *dest_entry;
+        xfs_acl_entry_t         *src_entry;
+
+        if (size < new_size)
+                return -ERANGE;
+
+        /* Need to sort src XFS ACL by <ae_tag,ae_id> */
+        qsort(src->acl_entry, src->acl_cnt, sizeof(src->acl_entry[0]),
+                xfs_acl_entry_compare);
+
+        dest->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION);
+        dest_entry = &dest->a_entries[0];
+        src_entry = &src->acl_entry[0];
+        for (n = 0; n < src->acl_cnt; n++, dest_entry++, src_entry++) {
+                dest_entry->e_perm = cpu_to_le16(src_entry->ae_perm);
+                if (_ACL_PERM_INVALID(src_entry->ae_perm))
+                        return -EINVAL;
+                dest_entry->e_tag  = cpu_to_le16(src_entry->ae_tag);
+                switch (src_entry->ae_tag) {
+                case ACL_USER:
+                case ACL_GROUP:
+                        dest_entry->e_id = cpu_to_le32(src_entry->ae_id);
+                                break;
+                case ACL_USER_OBJ:
+                case ACL_GROUP_OBJ:
+                case ACL_MASK:
+                case ACL_OTHER:
+                        dest_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
+                        break;
+                default:
+                        return -EINVAL;
+                }
+        }
+        return new_size;
+}
+
+int
+xfs_acl_vget(
+        vnode_t         *vp,
+        void            *acl,
+        size_t          size,
+        int             kind)
+{
+        int                     error;
+        xfs_acl_t               *xfs_acl = NULL;
+        posix_acl_xattr_header  *ext_acl = acl;
+        int                     flags = 0;
+
+        VN_HOLD(vp);
+        if(size) {
+                if (!(_ACL_ALLOC(xfs_acl))) {
+                        error = ENOMEM;
+                        goto out;
+                }
+                memset(xfs_acl, 0, sizeof(xfs_acl_t));
+        } else
+                flags = ATTR_KERNOVAL;
+
+        xfs_acl_get_attr(vp, xfs_acl, kind, flags, &error);
+        if (error)
+                goto out;
+
+        if (!size) {
+                error = -posix_acl_xattr_size(XFS_ACL_MAX_ENTRIES);
+        } else {
+                if (xfs_acl_invalid(xfs_acl)) {
+                        error = EINVAL;
+                        goto out;
+                }
+                if (kind == _ACL_TYPE_ACCESS) {
+                        vattr_t va;
+
+                        va.va_mask = XFS_AT_MODE;
+                        VOP_GETATTR(vp, &va, 0, sys_cred, error);
+                        if (error)
+                                goto out;
+                        xfs_acl_sync_mode(va.va_mode, xfs_acl);
+                }
+                error = -posix_acl_xfs_to_xattr(xfs_acl, ext_acl, size);
+        }
+out:
+        VN_RELE(vp);
+        if(xfs_acl)
+                _ACL_FREE(xfs_acl);
+        return -error;
+}
+
+int
+xfs_acl_vremove(
+        vnode_t         *vp,
+        int             kind)
+{
+        int             error;
+
+        VN_HOLD(vp);
+        error = xfs_acl_allow_set(vp, kind);
+        if (!error) {
+                VOP_ATTR_REMOVE(vp, kind == _ACL_TYPE_DEFAULT?
+                                SGI_ACL_DEFAULT: SGI_ACL_FILE,
+                                ATTR_ROOT, sys_cred, error);
+                if (error == ENOATTR)
+                        error = 0;      /* 'scool */
+        }
+        VN_RELE(vp);
+        return -error;
+}
+
+int
+xfs_acl_vset(
+        vnode_t                 *vp,
+        void                    *acl,
+        size_t                  size,
+        int                     kind)
+{
+        posix_acl_xattr_header  *ext_acl = acl;
+        xfs_acl_t               *xfs_acl;
+        int                     error;
+        int                     basicperms = 0; /* more than std unix perms? */
+
+        if (!acl)
+                return -EINVAL;
+
+        if (!(_ACL_ALLOC(xfs_acl)))
+                return -ENOMEM;
+
+        error = posix_acl_xattr_to_xfs(ext_acl, size, xfs_acl);
+        if (error) {
+                _ACL_FREE(xfs_acl);
+                return -error;
+        }
+        if (!xfs_acl->acl_cnt) {
+                _ACL_FREE(xfs_acl);
+                return 0;
+        }
+
+        VN_HOLD(vp);
+        error = xfs_acl_allow_set(vp, kind);
+        if (error)
+                goto out;
+
+        /* Incoming ACL exists, set file mode based on its value */
+        if (kind == _ACL_TYPE_ACCESS)
+                xfs_acl_setmode(vp, xfs_acl, &basicperms);
+
+        /*
+         * If we have more than std unix permissions, set up the actual attr.
+         * Otherwise, delete any existing attr.  This prevents us from
+         * having actual attrs for permissions that can be stored in the
+         * standard permission bits.
+         */
+        if (!basicperms) {
+                xfs_acl_set_attr(vp, xfs_acl, kind, &error);
+        } else {
+                xfs_acl_vremove(vp, _ACL_TYPE_ACCESS);
+        }
+
+out:
+        VN_RELE(vp);
+        _ACL_FREE(xfs_acl);
+        return -error;
+}
+
+int
+xfs_acl_iaccess(
+        xfs_inode_t     *ip,
+        mode_t          mode,
+        cred_t          *cr)
+{
+        xfs_acl_t       *acl;
+        int             rval;
+
+        if (!(_ACL_ALLOC(acl)))
+                return -1;
+
+        /* If the file has no ACL return -1. */
+        rval = sizeof(xfs_acl_t);
+        if (xfs_attr_fetch(ip, SGI_ACL_FILE, SGI_ACL_FILE_SIZE,
+                        (char *)acl, &rval, ATTR_ROOT | ATTR_KERNACCESS, cr)) {
+                _ACL_FREE(acl);
+                return -1;
+        }
+        xfs_acl_get_endian(acl);
+
+        /* If the file has an empty ACL return -1. */
+        if (acl->acl_cnt == XFS_ACL_NOT_PRESENT) {
+                _ACL_FREE(acl);
+                return -1;
+        }
+
+        /* Synchronize ACL with mode bits */
+        xfs_acl_sync_mode(ip->i_d.di_mode, acl);
+
+        rval = xfs_acl_access(ip->i_d.di_uid, ip->i_d.di_gid, acl, mode, cr);
+        _ACL_FREE(acl);
+        return rval;
+}
+
+STATIC int
+xfs_acl_allow_set(
+        vnode_t         *vp,
+        int             kind)
+{
+        vattr_t         va;
+        int             error;
+
+        if (vp->v_inode.i_flags & (S_IMMUTABLE|S_APPEND))
+                return EPERM;
+        if (kind == _ACL_TYPE_DEFAULT && vp->v_type != VDIR)
+                return ENOTDIR;
+        if (vp->v_vfsp->vfs_flag & VFS_RDONLY)
+                return EROFS;
+        va.va_mask = XFS_AT_UID;
+        VOP_GETATTR(vp, &va, 0, NULL, error);
+        if (error)
+                return error;
+        if (va.va_uid != current->fsuid && !capable(CAP_FOWNER))
+                return EPERM;
+        return error;
+}
+
+/*
+ * The access control process to determine the access permission:
+ *      if uid == file owner id, use the file owner bits.
+ *      if gid == file owner group id, use the file group bits.
+ *      scan ACL for a maching user or group, and use matched entry
+ *      permission. Use total permissions of all matching group entries,
+ *      until all acl entries are exhausted. The final permission produced
+ *      by matching acl entry or entries needs to be & with group permission.
+ *      if not owner, owning group, or matching entry in ACL, use file
+ *      other bits.  
+ */
+STATIC int
+xfs_acl_capability_check(
+        mode_t          mode,
+        cred_t          *cr)
+{
+        if ((mode & ACL_READ) && !capable_cred(cr, CAP_DAC_READ_SEARCH))
+                return EACCES;
+        if ((mode & ACL_WRITE) && !capable_cred(cr, CAP_DAC_OVERRIDE))
+                return EACCES;
+        if ((mode & ACL_EXECUTE) && !capable_cred(cr, CAP_DAC_OVERRIDE))
+                return EACCES;
+
+        return 0;
+}
+
+/*
+ * Note: cr is only used here for the capability check if the ACL test fails.
+ *       It is not used to find out the credentials uid or groups etc, as was
+ *       done in IRIX. It is assumed that the uid and groups for the current
+ *       thread are taken from "current" instead of the cr parameter.
+ */
+STATIC int
+xfs_acl_access(
+        uid_t           fuid,
+        gid_t           fgid,
+        xfs_acl_t       *fap,
+        mode_t          md,
+        cred_t          *cr)
+{
+        xfs_acl_entry_t matched;
+        int             i, allows;
+        int             maskallows = -1;        /* true, but not 1, either */
+        int             seen_userobj = 0;
+
+        matched.ae_tag = 0;     /* Invalid type */
+        md >>= 6;       /* Normalize the bits for comparison */
+
+        for (i = 0; i < fap->acl_cnt; i++) {
+                /*
+                 * Break out if we've got a user_obj entry or
+                 * a user entry and the mask (and have processed USER_OBJ)
+                 */
+                if (matched.ae_tag == ACL_USER_OBJ)
+                        break;
+                if (matched.ae_tag == ACL_USER) {
+                        if (maskallows != -1 && seen_userobj)
+                                break;
+                        if (fap->acl_entry[i].ae_tag != ACL_MASK &&
+                            fap->acl_entry[i].ae_tag != ACL_USER_OBJ)
+                                continue;
+                }
+                /* True if this entry allows the requested access */
+                allows = ((fap->acl_entry[i].ae_perm & md) == md);
+
+                switch (fap->acl_entry[i].ae_tag) {
+                case ACL_USER_OBJ:
+                        seen_userobj = 1;
+                        if (fuid != current->fsuid)
+                                continue;
+                        matched.ae_tag = ACL_USER_OBJ;
+                        matched.ae_perm = allows;
+                        break;
+                case ACL_USER:
+                        if (fap->acl_entry[i].ae_id != current->fsuid)
+                                continue;
+                        matched.ae_tag = ACL_USER;
+                        matched.ae_perm = allows;
+                        break;
+                case ACL_GROUP_OBJ:
+                        if ((matched.ae_tag == ACL_GROUP_OBJ ||
+                            matched.ae_tag == ACL_GROUP) && !allows)
+                                continue;
+                        if (!in_group_p(fgid))
+                                continue;
+                        matched.ae_tag = ACL_GROUP_OBJ;
+                        matched.ae_perm = allows;
+                        break;
+                case ACL_GROUP:
+                        if ((matched.ae_tag == ACL_GROUP_OBJ ||
+                            matched.ae_tag == ACL_GROUP) && !allows)
+                                continue;
+                        if (!in_group_p(fap->acl_entry[i].ae_id))
+                                continue;
+                        matched.ae_tag = ACL_GROUP;
+                        matched.ae_perm = allows;
+                        break;
+                case ACL_MASK:
+                        maskallows = allows;
+                        break;
+                case ACL_OTHER:
+                        if (matched.ae_tag != 0)
+                                continue;
+                        matched.ae_tag = ACL_OTHER;
+                        matched.ae_perm = allows;
+                        break;
+                }
+        }
+        /*
+         * First possibility is that no matched entry allows access.
+         * The capability to override DAC may exist, so check for it.
+         */
+        switch (matched.ae_tag) {
+        case ACL_OTHER:
+        case ACL_USER_OBJ:
+                if (matched.ae_perm)
+                        return 0;
+                break;
+        case ACL_USER:
+        case ACL_GROUP_OBJ:
+        case ACL_GROUP:
+                if (maskallows && matched.ae_perm)
+                        return 0;
+                break;
+        case 0:
+                break;
+        }
+
+        return xfs_acl_capability_check(md, cr);
+}
+
+/*
+ * ACL validity checker.
+ *   This acl validation routine checks each ACL entry read in makes sense.
+ */
+STATIC int
+xfs_acl_invalid(
+        xfs_acl_t       *aclp)
+{
+        xfs_acl_entry_t *entry, *e;
+        int             user = 0, group = 0, other = 0, mask = 0;
+        int             mask_required = 0;
+        int             i, j;
+
+        if (!aclp)
+                goto acl_invalid;
+
+        if (aclp->acl_cnt > XFS_ACL_MAX_ENTRIES)
+                goto acl_invalid;
+
+        for (i = 0; i < aclp->acl_cnt; i++) {
+                entry = &aclp->acl_entry[i];
+                switch (entry->ae_tag) {
+                case ACL_USER_OBJ:
+                        if (user++)
+                                goto acl_invalid;
+                        break;
+                case ACL_GROUP_OBJ:
+                        if (group++)
+                                goto acl_invalid;
+                        break;
+                case ACL_OTHER:
+                        if (other++)
+                                goto acl_invalid;
+                        break;
+                case ACL_USER:
+                case ACL_GROUP:
+                        for (j = i + 1; j < aclp->acl_cnt; j++) {
+                                e = &aclp->acl_entry[j];
+                                if (e->ae_id == entry->ae_id &&
+                                    e->ae_tag == entry->ae_tag)
+                                        goto acl_invalid;
+                        }
+                        mask_required++;
+                        break;
+                case ACL_MASK:
+                        if (mask++)
+                                goto acl_invalid;
+                        break;
+                default:
+                        goto acl_invalid;
+                }
+        }
+        if (!user || !group || !other || (mask_required && !mask))
+                goto acl_invalid;
+        else
+                return 0;
+acl_invalid:
+        return EINVAL;
+}
+
+/*
+ * Do ACL endian conversion.
+ */
+STATIC void
+xfs_acl_get_endian(
+        xfs_acl_t       *aclp)
+{
+        xfs_acl_entry_t *ace, *end;
+
+        INT_SET(aclp->acl_cnt, ARCH_CONVERT, aclp->acl_cnt);
+        end = &aclp->acl_entry[0]+aclp->acl_cnt;
+        for (ace = &aclp->acl_entry[0]; ace < end; ace++) {
+                INT_SET(ace->ae_tag, ARCH_CONVERT, ace->ae_tag);
+                INT_SET(ace->ae_id, ARCH_CONVERT, ace->ae_id);
+                INT_SET(ace->ae_perm, ARCH_CONVERT, ace->ae_perm);
+        }
+}
+
+/*
+ * Get the ACL from the EA and do endian conversion.
+ */
+STATIC void
+xfs_acl_get_attr(
+        vnode_t         *vp,
+        xfs_acl_t       *aclp,
+        int             kind,
+        int             flags,
+        int             *error)
+{
+        int             len = sizeof(xfs_acl_t);
+
+        ASSERT((flags & ATTR_KERNOVAL) ? (aclp == NULL) : 1);
+        flags |= ATTR_ROOT;
+        VOP_ATTR_GET(vp,
+                kind == _ACL_TYPE_ACCESS ? SGI_ACL_FILE : SGI_ACL_DEFAULT,
+                (char *)aclp, &len, flags, sys_cred, *error);
+        if (*error || (flags & ATTR_KERNOVAL))
+                return;
+        xfs_acl_get_endian(aclp);
+}
+
+/*
+ * Set the EA with the ACL and do endian conversion.
+ */
+STATIC void
+xfs_acl_set_attr(
+        vnode_t         *vp,
+        xfs_acl_t       *aclp,
+        int             kind,
+        int             *error)
+{
+        xfs_acl_entry_t *ace, *newace, *end;
+        xfs_acl_t       *newacl;
+        int             len;
+
+        if (!(_ACL_ALLOC(newacl))) {
+                *error = ENOMEM;
+                return;
+        }
+
+        len = sizeof(xfs_acl_t) -
+              (sizeof(xfs_acl_entry_t) * (XFS_ACL_MAX_ENTRIES - aclp->acl_cnt));
+        end = &aclp->acl_entry[0]+aclp->acl_cnt;
+        for (ace = &aclp->acl_entry[0], newace = &newacl->acl_entry[0];
+             ace < end;
+             ace++, newace++) {
+                INT_SET(newace->ae_tag, ARCH_CONVERT, ace->ae_tag);
+                INT_SET(newace->ae_id, ARCH_CONVERT, ace->ae_id);
+                INT_SET(newace->ae_perm, ARCH_CONVERT, ace->ae_perm);
+        }
+        INT_SET(newacl->acl_cnt, ARCH_CONVERT, aclp->acl_cnt);
+        VOP_ATTR_SET(vp,
+                kind == _ACL_TYPE_ACCESS ? SGI_ACL_FILE: SGI_ACL_DEFAULT,
+                (char *)newacl, len, ATTR_ROOT, sys_cred, *error);
+        _ACL_FREE(newacl);
+}
+
+int
+xfs_acl_vtoacl(
+        vnode_t         *vp,
+        xfs_acl_t       *access_acl,
+        xfs_acl_t       *default_acl)
+{
+        vattr_t         va;
+        int             error = 0;
+
+        if (access_acl) {
+                /*
+                 * Get the Access ACL and the mode.  If either cannot
+                 * be obtained for some reason, invalidate the access ACL.
+                 */
+                xfs_acl_get_attr(vp, access_acl, _ACL_TYPE_ACCESS, 0, &error);
+                if (!error) {
+                        /* Got the ACL, need the mode... */
+                        va.va_mask = XFS_AT_MODE;
+                        VOP_GETATTR(vp, &va, 0, sys_cred, error);
+                }
+
+                if (error)
+                        access_acl->acl_cnt = XFS_ACL_NOT_PRESENT;
+                else /* We have a good ACL and the file mode, synchronize. */
+                        xfs_acl_sync_mode(va.va_mode, access_acl);
+        }
+
+        if (default_acl) {
+                xfs_acl_get_attr(vp, default_acl, _ACL_TYPE_DEFAULT, 0, &error);
+                if (error)
+                        default_acl->acl_cnt = XFS_ACL_NOT_PRESENT;
+        }
+        return error;
+}
+
+/*
+ * This function retrieves the parent directory's acl, processes it
+ * and lets the child inherit the acl(s) that it should.
+ */
+int
+xfs_acl_inherit(
+        vnode_t         *vp,
+        vattr_t         *vap,
+        xfs_acl_t       *pdaclp)
+{
+        xfs_acl_t       *cacl;
+        int             error = 0;
+        int             basicperms = 0;
+
+        /*
+         * If the parent does not have a default ACL, or it's an
+         * invalid ACL, we're done.
+         */
+        if (!vp)
+                return 0;
+        if (!pdaclp || xfs_acl_invalid(pdaclp))
+                return 0;
+
+        /*
+         * Copy the default ACL of the containing directory to
+         * the access ACL of the new file and use the mode that
+         * was passed in to set up the correct initial values for
+         * the u::,g::[m::], and o:: entries.  This is what makes
+         * umask() "work" with ACL's.
+         */
+
+        if (!(_ACL_ALLOC(cacl)))
+                return ENOMEM;
+
+        memcpy(cacl, pdaclp, sizeof(xfs_acl_t));
+        xfs_acl_filter_mode(vap->va_mode, cacl);
+        xfs_acl_setmode(vp, cacl, &basicperms);
+
+        /*
+         * Set the Default and Access ACL on the file.  The mode is already
+         * set on the file, so we don't need to worry about that.
+         *
+         * If the new file is a directory, its default ACL is a copy of
+         * the containing directory's default ACL.
+         */
+        if (vp->v_type == VDIR)
+                xfs_acl_set_attr(vp, pdaclp, _ACL_TYPE_DEFAULT, &error);
+        if (!error && !basicperms)
+                xfs_acl_set_attr(vp, cacl, _ACL_TYPE_ACCESS, &error);
+        _ACL_FREE(cacl);
+        return error;
+}
+
+/*
+ * Set up the correct mode on the file based on the supplied ACL.  This
+ * makes sure that the mode on the file reflects the state of the
+ * u::,g::[m::], and o:: entries in the ACL.  Since the mode is where
+ * the ACL is going to get the permissions for these entries, we must
+ * synchronize the mode whenever we set the ACL on a file.
+ */
+STATIC int
+xfs_acl_setmode(
+        vnode_t         *vp,
+        xfs_acl_t       *acl,
+        int             *basicperms)
+{
+        vattr_t         va;
+        xfs_acl_entry_t *ap;
+        xfs_acl_entry_t *gap = NULL;
+        int             i, error, nomask = 1;
+
+        *basicperms = 1;
+
+        if (acl->acl_cnt == XFS_ACL_NOT_PRESENT)
+                return 0;
+
+        /*
+         * Copy the u::, g::, o::, and m:: bits from the ACL into the
+         * mode.  The m:: bits take precedence over the g:: bits.
+         */
+        va.va_mask = XFS_AT_MODE;
+        VOP_GETATTR(vp, &va, 0, sys_cred, error);
+        if (error)
+                return error;
+
+        va.va_mask = XFS_AT_MODE;
+        va.va_mode &= ~(S_IRWXU|S_IRWXG|S_IRWXO);
+        ap = acl->acl_entry;
+        for (i = 0; i < acl->acl_cnt; ++i) {
+                switch (ap->ae_tag) {
+                case ACL_USER_OBJ:
+                        va.va_mode |= ap->ae_perm << 6;
+                        break;
+                case ACL_GROUP_OBJ:
+                        gap = ap;
+                        break;
+                case ACL_MASK:  /* more than just standard modes */
+                        nomask = 0;
+                        va.va_mode |= ap->ae_perm << 3;
+                        *basicperms = 0;
+                        break;
+                case ACL_OTHER:
+                        va.va_mode |= ap->ae_perm;
+                        break;
+                default:        /* more than just standard modes */
+                        *basicperms = 0;
+                        break;
+                }
+                ap++;
+        }
+
+        /* Set the group bits from ACL_GROUP_OBJ if there's no ACL_MASK */
+        if (gap && nomask)
+                va.va_mode |= gap->ae_perm << 3;
+
+        VOP_SETATTR(vp, &va, 0, sys_cred, error);
+        return error;
+}
+
+/*
+ * The permissions for the special ACL entries (u::, g::[m::], o::) are
+ * actually stored in the file mode (if there is both a group and a mask,
+ * the group is stored in the ACL entry and the mask is stored on the file).
+ * This allows the mode to remain automatically in sync with the ACL without
+ * the need for a call-back to the ACL system at every point where the mode
+ * could change.  This function takes the permissions from the specified mode
+ * and places it in the supplied ACL.
+ *
+ * This implementation draws its validity from the fact that, when the ACL
+ * was assigned, the mode was copied from the ACL.
+ * If the mode did not change, therefore, the mode remains exactly what was
+ * taken from the special ACL entries at assignment.
+ * If a subsequent chmod() was done, the POSIX spec says that the change in
+ * mode must cause an update to the ACL seen at user level and used for
+ * access checks.  Before and after a mode change, therefore, the file mode
+ * most accurately reflects what the special ACL entries should permit/deny.
+ *
+ * CAVEAT: If someone sets the SGI_ACL_FILE attribute directly,
+ *         the existing mode bits will override whatever is in the
+ *         ACL. Similarly, if there is a pre-existing ACL that was
+ *         never in sync with its mode (owing to a bug in 6.5 and
+ *         before), it will now magically (or mystically) be
+ *         synchronized.  This could cause slight astonishment, but
+ *         it is better than inconsistent permissions.
+ *
+ * The supplied ACL is a template that may contain any combination
+ * of special entries.  These are treated as place holders when we fill
+ * out the ACL.  This routine does not add or remove special entries, it
+ * simply unites each special entry with its associated set of permissions.
+ */
+STATIC void
+xfs_acl_sync_mode(
+        mode_t          mode,
+        xfs_acl_t       *acl)
+{
+        int             i, nomask = 1;
+        xfs_acl_entry_t *ap;
+        xfs_acl_entry_t *gap = NULL;
+
+        /*
+         * Set ACL entries. POSIX1003.1eD16 requires that the MASK
+         * be set instead of the GROUP entry, if there is a MASK.
+         */
+        for (ap = acl->acl_entry, i = 0; i < acl->acl_cnt; ap++, i++) {
+                switch (ap->ae_tag) {
+                case ACL_USER_OBJ:
+                        ap->ae_perm = (mode >> 6) & 0x7;
+                        break;
+                case ACL_GROUP_OBJ:
+                        gap = ap;
+                        break;
+                case ACL_MASK:
+                        nomask = 0;
+                        ap->ae_perm = (mode >> 3) & 0x7;
+                        break;
+                case ACL_OTHER:
+                        ap->ae_perm = mode & 0x7;
+                        break;
+                default:
+                        break;
+                }
+        }
+        /* Set the ACL_GROUP_OBJ if there's no ACL_MASK */
+        if (gap && nomask)
+                gap->ae_perm = (mode >> 3) & 0x7;
+}
+
+/*
+ * When inheriting an Access ACL from a directory Default ACL,
+ * the ACL bits are set to the intersection of the ACL default
+ * permission bits and the file permission bits in mode. If there
+ * are no permission bits on the file then we must not give them
+ * the ACL. This is what what makes umask() work with ACLs.
+ */
+STATIC void
+xfs_acl_filter_mode(
+        mode_t          mode,
+        xfs_acl_t       *acl)
+{
+        int             i, nomask = 1;
+        xfs_acl_entry_t *ap;
+        xfs_acl_entry_t *gap = NULL;
+
+        /*
+         * Set ACL entries. POSIX1003.1eD16 requires that the MASK
+         * be merged with GROUP entry, if there is a MASK.
+         */
+        for (ap = acl->acl_entry, i = 0; i < acl->acl_cnt; ap++, i++) {
+                switch (ap->ae_tag) {
+                case ACL_USER_OBJ:
+                        ap->ae_perm &= (mode >> 6) & 0x7;
+                        break;
+                case ACL_GROUP_OBJ:
+                        gap = ap;
+                        break;
+                case ACL_MASK:
+                        nomask = 0;
+                        ap->ae_perm &= (mode >> 3) & 0x7;
+                        break;
+                case ACL_OTHER:
+                        ap->ae_perm &= mode & 0x7;
+                        break;
+                default:
+                        break;
+                }
+        }
+        /* Set the ACL_GROUP_OBJ if there's no ACL_MASK */
+        if (gap && nomask)
+                gap->ae_perm &= (mode >> 3) & 0x7;
+}