1 files changed, 209 insertions, 148 deletions

diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c
index 3fc4e3ac7d84..3eb1ea846173 100644
--- a/fs/gfs2/acl.c
+++ b/fs/gfs2/acl.c
@@ -12,6 +12,7 @@
 #include <linux/spinlock.h>
 #include <linux/completion.h>
 #include <linux/buffer_head.h>
+#include <linux/xattr.h>
 #include <linux/posix_acl.h>
 #include <linux/posix_acl_xattr.h>
 #include <linux/gfs2_ondisk.h>
@@ -26,108 +27,44 @@
 #include "trans.h"
 #include "util.h"
 
-#define ACL_ACCESS 1
-#define ACL_DEFAULT 0
-
-int gfs2_acl_validate_set(struct gfs2_inode *ip, int access,
-                          struct gfs2_ea_request *er, int *remove, mode_t *mode)
+static const char *gfs2_acl_name(int type)
 {
-        struct posix_acl *acl;
-        int error;
-
-        error = gfs2_acl_validate_remove(ip, access);
-        if (error)
-                return error;
-
-        if (!er->er_data)
-                return -EINVAL;
-
-        acl = posix_acl_from_xattr(er->er_data, er->er_data_len);
-        if (IS_ERR(acl))
-                return PTR_ERR(acl);
-        if (!acl) {
-                *remove = 1;
-                return 0;
-        }
-
-        error = posix_acl_valid(acl);
-        if (error)
-                goto out;
-
-        if (access) {
-                error = posix_acl_equiv_mode(acl, mode);
-                if (!error)
-                        *remove = 1;
-                else if (error > 0)
-                        error = 0;
+        switch (type) {
+        case ACL_TYPE_ACCESS:
+                return GFS2_POSIX_ACL_ACCESS;
+        case ACL_TYPE_DEFAULT:
+                return GFS2_POSIX_ACL_DEFAULT;
         }
-
-out:
-        posix_acl_release(acl);
-        return error;
-}
-
-int gfs2_acl_validate_remove(struct gfs2_inode *ip, int access)
-{
-        if (!GFS2_SB(&ip->i_inode)->sd_args.ar_posix_acl)
-                return -EOPNOTSUPP;
-        if (!is_owner_or_cap(&ip->i_inode))
-                return -EPERM;
-        if (S_ISLNK(ip->i_inode.i_mode))
-                return -EOPNOTSUPP;
-        if (!access && !S_ISDIR(ip->i_inode.i_mode))
-                return -EACCES;
-
-        return 0;
+        return NULL;
 }
 
-static int acl_get(struct gfs2_inode *ip, const char *name,
-                   struct posix_acl **acl, struct gfs2_ea_location *el,
-                   char **datap, unsigned int *lenp)
+static struct posix_acl *gfs2_acl_get(struct gfs2_inode *ip, int type)
 {
+        struct posix_acl *acl;
+        const char *name;
         char *data;
-        unsigned int len;
-        int error;
-
-        el->el_bh = NULL;
+        int len;
 
         if (!ip->i_eattr)
-                return 0;
-
-        error = gfs2_ea_find(ip, GFS2_EATYPE_SYS, name, el);
-        if (error)
-                return error;
-        if (!el->el_ea)
-                return 0;
-        if (!GFS2_EA_DATA_LEN(el->el_ea))
-                goto out;
+                return NULL;
 
-        len = GFS2_EA_DATA_LEN(el->el_ea);
-        data = kmalloc(len, GFP_NOFS);
-        error = -ENOMEM;
-        if (!data)
-                goto out;
+        acl = get_cached_acl(&ip->i_inode, type);
+        if (acl != ACL_NOT_CACHED)
+                return acl;
 
-        error = gfs2_ea_get_copy(ip, el, data, len);
-        if (error < 0)
-                goto out_kfree;
-        error = 0;
+        name = gfs2_acl_name(type);
+        if (name == NULL)
+                return ERR_PTR(-EINVAL);
 
-        if (acl) {
-                *acl = posix_acl_from_xattr(data, len);
-                if (IS_ERR(*acl))
-                        error = PTR_ERR(*acl);
-        }
+        len = gfs2_xattr_acl_get(ip, name, &data);
+        if (len < 0)
+                return ERR_PTR(len);
+        if (len == 0)
+                return NULL;
 
-out_kfree:
-        if (error || !datap) {
-                kfree(data);
-        } else {
-                *datap = data;
-                *lenp = len;
-        }
-out:
-        return error;
+        acl = posix_acl_from_xattr(data, len);
+        kfree(data);
+        return acl;
 }
 
 /**
@@ -140,14 +77,12 @@ out:
 
 int gfs2_check_acl(struct inode *inode, int mask)
 {
-        struct gfs2_ea_location el;
-        struct posix_acl *acl = NULL;
+        struct posix_acl *acl;
         int error;
 
-        error = acl_get(GFS2_I(inode), GFS2_POSIX_ACL_ACCESS, &acl, &el, NULL, NULL);
-        brelse(el.el_bh);
-        if (error)
-                return error;
+        acl = gfs2_acl_get(GFS2_I(inode), ACL_TYPE_ACCESS);
+        if (IS_ERR(acl))
+                return PTR_ERR(acl);
 
         if (acl) {
                 error = posix_acl_permission(inode, acl, mask);
@@ -158,57 +93,75 @@ int gfs2_check_acl(struct inode *inode, int mask)
         return -EAGAIN;
 }
 
-static int munge_mode(struct gfs2_inode *ip, mode_t mode)
+static int gfs2_set_mode(struct inode *inode, mode_t mode)
 {
-        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
-        struct buffer_head *dibh;
-        int error;
+        int error = 0;
 
-        error = gfs2_trans_begin(sdp, RES_DINODE, 0);
-        if (error)
-                return error;
+        if (mode != inode->i_mode) {
+                struct iattr iattr;
 
-        error = gfs2_meta_inode_buffer(ip, &dibh);
-        if (!error) {
-                gfs2_assert_withdraw(sdp,
-                                (ip->i_inode.i_mode & S_IFMT) == (mode & S_IFMT));
-                ip->i_inode.i_mode = mode;
-                gfs2_trans_add_bh(ip->i_gl, dibh, 1);
-                gfs2_dinode_out(ip, dibh->b_data);
-                brelse(dibh);
+                iattr.ia_valid = ATTR_MODE;
+                iattr.ia_mode = mode;
+
+                error = gfs2_setattr_simple(GFS2_I(inode), &iattr);
         }
 
-        gfs2_trans_end(sdp);
+        return error;
+}
+
+static int gfs2_acl_set(struct inode *inode, int type, struct posix_acl *acl)
+{
+        int error;
+        int len;
+        char *data;
+        const char *name = gfs2_acl_name(type);
 
-        return 0;
+        BUG_ON(name == NULL);
+        len = posix_acl_to_xattr(acl, NULL, 0);
+        if (len == 0)
+                return 0;
+        data = kmalloc(len, GFP_NOFS);
+        if (data == NULL)
+                return -ENOMEM;
+        error = posix_acl_to_xattr(acl, data, len);
+        if (error < 0)
+                goto out;
+        error = gfs2_xattr_set(inode, GFS2_EATYPE_SYS, name, data, len, 0);
+        if (!error)
+                set_cached_acl(inode, type, acl);
+out:
+        kfree(data);
+        return error;
 }
 
-int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip)
+int gfs2_acl_create(struct gfs2_inode *dip, struct inode *inode)
 {
-        struct gfs2_ea_location el;
         struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
-        struct posix_acl *acl = NULL, *clone;
-        mode_t mode = ip->i_inode.i_mode;
-        char *data = NULL;
-        unsigned int len;
-        int error;
+        struct posix_acl *acl, *clone;
+        mode_t mode = inode->i_mode;
+        int error = 0;
 
         if (!sdp->sd_args.ar_posix_acl)
                 return 0;
-        if (S_ISLNK(ip->i_inode.i_mode))
+        if (S_ISLNK(inode->i_mode))
                 return 0;
 
-        error = acl_get(dip, GFS2_POSIX_ACL_DEFAULT, &acl, &el, &data, &len);
-        brelse(el.el_bh);
-        if (error)
-                return error;
+        acl = gfs2_acl_get(dip, ACL_TYPE_DEFAULT);
+        if (IS_ERR(acl))
+                return PTR_ERR(acl);
         if (!acl) {
                 mode &= ~current_umask();
-                if (mode != ip->i_inode.i_mode)
-                        error = munge_mode(ip, mode);
+                if (mode != inode->i_mode)
+                        error = gfs2_set_mode(inode, mode);
                 return error;
         }
 
+        if (S_ISDIR(inode->i_mode)) {
+                error = gfs2_acl_set(inode, ACL_TYPE_DEFAULT, acl);
+                if (error)
+                        goto out;
+        }
+
         clone = posix_acl_clone(acl, GFP_NOFS);
         error = -ENOMEM;
         if (!clone)
@@ -216,43 +169,32 @@ int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip)
         posix_acl_release(acl);
         acl = clone;
 
-        if (S_ISDIR(ip->i_inode.i_mode)) {
-                error = gfs2_xattr_set(&ip->i_inode, GFS2_EATYPE_SYS,
-                                       GFS2_POSIX_ACL_DEFAULT, data, len, 0);
-                if (error)
-                        goto out;
-        }
-
         error = posix_acl_create_masq(acl, &mode);
         if (error < 0)
                 goto out;
         if (error == 0)
                 goto munge;
 
-        posix_acl_to_xattr(acl, data, len);
-        error = gfs2_xattr_set(&ip->i_inode, GFS2_EATYPE_SYS,
-                               GFS2_POSIX_ACL_ACCESS, data, len, 0);
+        error = gfs2_acl_set(inode, ACL_TYPE_ACCESS, acl);
         if (error)
                 goto out;
 munge:
-        error = munge_mode(ip, mode);
+        error = gfs2_set_mode(inode, mode);
 out:
         posix_acl_release(acl);
-        kfree(data);
         return error;
 }
 
 int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr)
 {
-        struct posix_acl *acl = NULL, *clone;
-        struct gfs2_ea_location el;
+        struct posix_acl *acl, *clone;
         char *data;
         unsigned int len;
         int error;
 
-        error = acl_get(ip, GFS2_POSIX_ACL_ACCESS, &acl, &el, &data, &len);
-        if (error)
-                goto out_brelse;
+        acl = gfs2_acl_get(ip, ACL_TYPE_ACCESS);
+        if (IS_ERR(acl))
+                return PTR_ERR(acl);
         if (!acl)
                 return gfs2_setattr_simple(ip, attr);
 
@@ -265,15 +207,134 @@ int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr)
 
         error = posix_acl_chmod_masq(acl, attr->ia_mode);
         if (!error) {
+                len = posix_acl_to_xattr(acl, NULL, 0);
+                data = kmalloc(len, GFP_NOFS);
+                error = -ENOMEM;
+                if (data == NULL)
+                        goto out;
                 posix_acl_to_xattr(acl, data, len);
-                error = gfs2_ea_acl_chmod(ip, &el, attr, data);
+                error = gfs2_xattr_acl_chmod(ip, attr, data);
+                kfree(data);
+                set_cached_acl(&ip->i_inode, ACL_TYPE_ACCESS, acl);
         }
 
 out:
         posix_acl_release(acl);
-        kfree(data);
-out_brelse:
-        brelse(el.el_bh);
         return error;
 }
 
+static int gfs2_acl_type(const char *name)
+{
+        if (strcmp(name, GFS2_POSIX_ACL_ACCESS) == 0)
+                return ACL_TYPE_ACCESS;
+        if (strcmp(name, GFS2_POSIX_ACL_DEFAULT) == 0)
+                return ACL_TYPE_DEFAULT;
+        return -EINVAL;
+}
+
+static int gfs2_xattr_system_get(struct inode *inode, const char *name,
+                                 void *buffer, size_t size)
+{
+        struct posix_acl *acl;
+        int type;
+        int error;
+
+        type = gfs2_acl_type(name);
+        if (type < 0)
+                return type;
+
+        acl = gfs2_acl_get(GFS2_I(inode), type);
+        if (IS_ERR(acl))
+                return PTR_ERR(acl);
+        if (acl == NULL)
+                return -ENODATA;
+
+        error = posix_acl_to_xattr(acl, buffer, size);
+        posix_acl_release(acl);
+
+        return error;
+}
+
+static int gfs2_xattr_system_set(struct inode *inode, const char *name,
+                                 const void *value, size_t size, int flags)
+{
+        struct gfs2_sbd *sdp = GFS2_SB(inode);
+        struct posix_acl *acl = NULL;
+        int error = 0, type;
+
+        if (!sdp->sd_args.ar_posix_acl)
+                return -EOPNOTSUPP;
+
+        type = gfs2_acl_type(name);
+        if (type < 0)
+                return type;
+        if (flags & XATTR_CREATE)
+                return -EINVAL;
+        if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
+                return value ? -EACCES : 0;
+        if ((current_fsuid() != inode->i_uid) && !capable(CAP_FOWNER))
+                return -EPERM;
+        if (S_ISLNK(inode->i_mode))
+                return -EOPNOTSUPP;
+
+        if (!value)
+                goto set_acl;
+
+        acl = posix_acl_from_xattr(value, size);
+        if (!acl) {
+                /*
+                 * acl_set_file(3) may request that we set default ACLs with
+                 * zero length -- defend (gracefully) against that here.
+                 */
+                goto out;
+        }
+        if (IS_ERR(acl)) {
+                error = PTR_ERR(acl);
+                goto out;
+        }
+
+        error = posix_acl_valid(acl);
+        if (error)
+                goto out_release;
+
+        error = -EINVAL;
+        if (acl->a_count > GFS2_ACL_MAX_ENTRIES)
+                goto out_release;
+
+        if (type == ACL_TYPE_ACCESS) {
+                mode_t mode = inode->i_mode;
+                error = posix_acl_equiv_mode(acl, &mode);
+
+                if (error <= 0) {
+                        posix_acl_release(acl);
+                        acl = NULL;
+
+                        if (error < 0)
+                                return error;
+                }
+
+                error = gfs2_set_mode(inode, mode);
+                if (error)
+                        goto out_release;
+        }
+
+set_acl:
+        error = gfs2_xattr_set(inode, GFS2_EATYPE_SYS, name, value, size, 0);
+        if (!error) {
+                if (acl)
+                        set_cached_acl(inode, type, acl);
+                else
+                        forget_cached_acl(inode, type);
+        }
+out_release:
+        posix_acl_release(acl);
+out:
+        return error;
+}
+
+struct xattr_handler gfs2_xattr_system_handler = {
+        .prefix = XATTR_SYSTEM_PREFIX,
+        .get    = gfs2_xattr_system_get,
+        .set    = gfs2_xattr_system_set,
+};
+