GFS2: Clean up of extended attribute support

This has been on my list for some time. We need to change the way
in which we handle extended attributes to allow faster file creation
times (by reducing the number of transactions required) and the
extended attribute code is the main obstacle to this.

In addition to that, the VFS provides a way to demultiplex the xattr
calls which we ought to be using, rather than rolling our own. This
patch changes the GFS2 code to use that VFS feature and as a result
the code shrinks by a couple of hundred lines or so, and becomes
easier to read.

I'm planning on doing further clean up work in this area, but this
patch is a good start. The cleaned up code also uses the more usual
"xattr" shorthand, I plan to eliminate the use of "eattr" eventually
and in the mean time it serves as a flag as to which bits of the code
have been updated.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 45 insertions, 59 deletions

diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c
index fa881bdc3d85..f6777f167260 100644
--- a/fs/gfs2/acl.c
+++ b/fs/gfs2/acl.c
@@ -19,7 +19,6 @@
 #include "gfs2.h"
 #include "incore.h"
 #include "acl.h"
-#include "eaops.h"
 #include "eattr.h"
 #include "glock.h"
 #include "inode.h"
@@ -31,8 +30,7 @@
 #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)
+                          struct gfs2_ea_request *er, int *remove, mode_t *mode)
 {
         struct posix_acl *acl;
         int error;
@@ -83,30 +81,20 @@ int gfs2_acl_validate_remove(struct gfs2_inode *ip, int access)
         return 0;
 }
 
-static int acl_get(struct gfs2_inode *ip, int access, struct posix_acl **acl,
-                   struct gfs2_ea_location *el, char **data, unsigned int *len)
+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)
 {
-        struct gfs2_ea_request er;
-        struct gfs2_ea_location el_this;
+        char *data;
+        unsigned int len;
         int error;
 
+        el->el_bh = NULL;
+
         if (!ip->i_eattr)
                 return 0;
 
-        memset(&er, 0, sizeof(struct gfs2_ea_request));
-        if (access) {
-                er.er_name = GFS2_POSIX_ACL_ACCESS;
-                er.er_name_len = GFS2_POSIX_ACL_ACCESS_LEN;
-        } else {
-                er.er_name = GFS2_POSIX_ACL_DEFAULT;
-                er.er_name_len = GFS2_POSIX_ACL_DEFAULT_LEN;
-        }
-        er.er_type = GFS2_EATYPE_SYS;
-
-        if (!el)
-                el = &el_this;
-
-        error = gfs2_ea_find(ip, &er, el);
+        error = gfs2_ea_find(ip, GFS2_EATYPE_SYS, name, el);
         if (error)
                 return error;
         if (!el->el_ea)
@@ -114,32 +102,31 @@ static int acl_get(struct gfs2_inode *ip, int access, struct posix_acl **acl,
         if (!GFS2_EA_DATA_LEN(el->el_ea))
                 goto out;
 
-        er.er_data_len = GFS2_EA_DATA_LEN(el->el_ea);
-        er.er_data = kmalloc(er.er_data_len, GFP_NOFS);
+        len = GFS2_EA_DATA_LEN(el->el_ea);
+        data = kmalloc(len, GFP_NOFS);
         error = -ENOMEM;
-        if (!er.er_data)
+        if (!data)
                 goto out;
 
-        error = gfs2_ea_get_copy(ip, el, er.er_data);
-        if (error)
+        error = gfs2_ea_get_copy(ip, el, data, len);
+        if (error < 0)
                 goto out_kfree;
+        error = 0;
 
         if (acl) {
-                *acl = posix_acl_from_xattr(er.er_data, er.er_data_len);
+                *acl = posix_acl_from_xattr(data, len);
                 if (IS_ERR(*acl))
                         error = PTR_ERR(*acl);
         }
 
 out_kfree:
-        if (error || !data)
-                kfree(er.er_data);
-        else {
-                *data = er.er_data;
-                *len = er.er_data_len;
+        if (error || !datap) {
+                kfree(data);
+        } else {
+                *datap = data;
+                *lenp = len;
         }
 out:
-        if (error || el == &el_this)
-                brelse(el->el_bh);
         return error;
 }
 
@@ -153,10 +140,12 @@ out:
 
 int gfs2_check_acl(struct inode *inode, int mask)
 {
+        struct gfs2_ea_location el;
         struct posix_acl *acl = NULL;
         int error;
 
-        error = acl_get(GFS2_I(inode), ACL_ACCESS, &acl, NULL, NULL, NULL);
+        error = acl_get(GFS2_I(inode), GFS2_POSIX_ACL_ACCESS, &acl, &el, NULL, NULL);
+        brelse(el.el_bh);
         if (error)
                 return error;
 
@@ -196,10 +185,12 @@ static int munge_mode(struct gfs2_inode *ip, mode_t mode)
 
 int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip)
 {
+        struct gfs2_ea_location el;
         struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
         struct posix_acl *acl = NULL, *clone;
-        struct gfs2_ea_request er;
         mode_t mode = ip->i_inode.i_mode;
+        char *data = NULL;
+        unsigned int len;
         int error;
 
         if (!sdp->sd_args.ar_posix_acl)
@@ -207,11 +198,8 @@ int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip)
         if (S_ISLNK(ip->i_inode.i_mode))
                 return 0;
 
-        memset(&er, 0, sizeof(struct gfs2_ea_request));
-        er.er_type = GFS2_EATYPE_SYS;
-
-        error = acl_get(dip, ACL_DEFAULT, &acl, NULL,
-                        &er.er_data, &er.er_data_len);
+        error = acl_get(dip, GFS2_POSIX_ACL_DEFAULT, &acl, &el, &data, &len);
+        brelse(el.el_bh);
         if (error)
                 return error;
         if (!acl) {
@@ -229,9 +217,8 @@ int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip)
         acl = clone;
 
         if (S_ISDIR(ip->i_inode.i_mode)) {
-                er.er_name = GFS2_POSIX_ACL_DEFAULT;
-                er.er_name_len = GFS2_POSIX_ACL_DEFAULT_LEN;
-                error = gfs2_system_eaops.eo_set(ip, &er);
+                error = gfs2_xattr_set(&ip->i_inode, GFS2_EATYPE_SYS,
+                                       GFS2_POSIX_ACL_DEFAULT, data, len, 0);
                 if (error)
                         goto out;
         }
@@ -239,21 +226,19 @@ int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip)
         error = posix_acl_create_masq(acl, &mode);
         if (error < 0)
                 goto out;
-        if (error > 0) {
-                er.er_name = GFS2_POSIX_ACL_ACCESS;
-                er.er_name_len = GFS2_POSIX_ACL_ACCESS_LEN;
-                posix_acl_to_xattr(acl, er.er_data, er.er_data_len);
-                er.er_mode = mode;
-                er.er_flags = GFS2_ERF_MODE;
-                error = gfs2_system_eaops.eo_set(ip, &er);
-                if (error)
-                        goto out;
-        } else
-                munge_mode(ip, mode);
+        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);
+        if (error)
+                goto out;
+munge:
+        error = munge_mode(ip, mode);
 out:
         posix_acl_release(acl);
-        kfree(er.er_data);
+        kfree(data);
         return error;
 }
 
@@ -265,9 +250,9 @@ int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr)
         unsigned int len;
         int error;
 
-        error = acl_get(ip, ACL_ACCESS, &acl, &el, &data, &len);
+        error = acl_get(ip, GFS2_POSIX_ACL_ACCESS, &acl, &el, &data, &len);
         if (error)
-                return error;
+                goto out_brelse;
         if (!acl)
                 return gfs2_setattr_simple(ip, attr);
 
@@ -286,8 +271,9 @@ int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr)
 
 out:
         posix_acl_release(acl);
-        brelse(el.el_bh);
         kfree(data);
+out_brelse:
+        brelse(el.el_bh);
         return error;
 }