[XFS] Dynamically allocate vattr in places it makes sense to do so, to

reduce stack use.  Also re-use vattr in some places so that multiple
copies are not held on-stack.

SGI-PV: 947312
SGI-Modid: xfs-linux-melb:xfs-kern:25369a

Signed-off-by: Nathan Scott <nathans@sgi.com>

1 files changed, 105 insertions, 75 deletions

diff --git a/fs/xfs/linux-2.6/xfs_iops.c b/fs/xfs/linux-2.6/xfs_iops.c
index d7f6f2d8ac8e..b1219195c6e2 100644
--- a/fs/xfs/linux-2.6/xfs_iops.c
+++ b/fs/xfs/linux-2.6/xfs_iops.c
@@ -198,22 +198,22 @@ xfs_ichgtime_fast(
  * Pull the link count and size up from the xfs inode to the linux inode
  */
 STATIC void
-validate_fields(
-        struct inode    *ip)
+__linvfs_validate_fields(
+        struct inode    *ip,
+        struct vattr    *vattr)
 {
         vnode_t         *vp = LINVFS_GET_VP(ip);
-        vattr_t         va;
         int             error;
 
-        va.va_mask = XFS_AT_NLINK|XFS_AT_SIZE|XFS_AT_NBLOCKS;
-        VOP_GETATTR(vp, &va, ATTR_LAZY, NULL, error);
-        if (likely(!error)) {
-                ip->i_nlink = va.va_nlink;
-                ip->i_blocks = va.va_nblocks;
+        vattr->va_mask = XFS_AT_NLINK|XFS_AT_SIZE|XFS_AT_NBLOCKS;
+        VOP_GETATTR(vp, vattr, ATTR_LAZY, NULL, error);
+        if (likely(!error)) {
+                ip->i_nlink = vattr->va_nlink;
+                ip->i_blocks = vattr->va_nblocks;
 
-                /* we're under i_mutex so i_size can't change under us */
-                if (i_size_read(ip) != va.va_size)
-                        i_size_write(ip, va.va_size);
+                /* we're under i_sem so i_size can't change under us */
+                if (i_size_read(ip) != vattr->va_size)
+                        i_size_write(ip, vattr->va_size);
         }
 }
 
@@ -224,7 +224,7 @@ validate_fields(
  * inode, of course, such that log replay can't cause these to be lost).
  */
 STATIC int
-linvfs_init_security(
+__linvfs_init_security(
         struct vnode    *vp,
         struct inode    *dir)
 {
@@ -257,23 +257,23 @@ linvfs_init_security(
  * XXX(hch):  nfsd is broken, better fix it instead.
  */
 STATIC inline int
-has_fs_struct(struct task_struct *task)
+__linvfs_has_fs_struct(struct task_struct *task)
 {
         return (task->fs != init_task.fs);
 }
 
 STATIC inline void
-cleanup_inode(
+__linvfs_cleanup_inode(
         vnode_t         *dvp,
         vnode_t         *vp,
-        struct dentry   *dentry,        
+        struct dentry   *dentry,
         int             mode)
 {
         struct dentry   teardown = {};
-        int             err2;
+        int             error;
 
         /* Oh, the horror.
-         * If we can't add the ACL or we fail in 
+         * If we can't add the ACL or we fail in
          * linvfs_init_security we must back out.
          * ENOSPC can hit here, among other things.
          */
@@ -281,9 +281,9 @@ cleanup_inode(
         teardown.d_name = dentry->d_name;
 
         if (S_ISDIR(mode))
-                VOP_RMDIR(dvp, &teardown, NULL, err2);
+                VOP_RMDIR(dvp, &teardown, NULL, error);
         else
-                VOP_REMOVE(dvp, &teardown, NULL, err2);
+                VOP_REMOVE(dvp, &teardown, NULL, error);
         VN_RELE(vp);
 }
 
@@ -295,7 +295,7 @@ linvfs_mknod(
         dev_t           rdev)
 {
         struct inode    *ip;
-        vattr_t         va;
+        vattr_t         *vattr;
         vnode_t         *vp = NULL, *dvp = LINVFS_GET_VP(dir);
         xfs_acl_t       *default_acl = NULL;
         attrexists_t    test_default_acl = _ACL_DEFAULT_EXISTS;
@@ -305,70 +305,76 @@ linvfs_mknod(
          * Irix uses Missed'em'V split, but doesn't want to see
          * the upper 5 bits of (14bit) major.
          */
-        if (!sysv_valid_dev(rdev) || MAJOR(rdev) & ~0x1ff)
+        if (unlikely(!sysv_valid_dev(rdev) || MAJOR(rdev) & ~0x1ff))
                 return -EINVAL;
 
-        if (test_default_acl && test_default_acl(dvp)) {
-                if (!_ACL_ALLOC(default_acl))
+        vattr = kmalloc(sizeof(*vattr), GFP_KERNEL);
+        if (unlikely(!vattr))
+                return -ENOMEM;
+
+        if (unlikely(test_default_acl && test_default_acl(dvp))) {
+                if (!_ACL_ALLOC(default_acl)) {
+                        kfree(vattr);
                         return -ENOMEM;
+                }
                 if (!_ACL_GET_DEFAULT(dvp, default_acl)) {
                         _ACL_FREE(default_acl);
                         default_acl = NULL;
                 }
         }
 
-        if (IS_POSIXACL(dir) && !default_acl && has_fs_struct(current))
+        if (IS_POSIXACL(dir) && !default_acl && __linvfs_has_fs_struct(current))
                 mode &= ~current->fs->umask;
 
-        memset(&va, 0, sizeof(va));
-        va.va_mask = XFS_AT_TYPE|XFS_AT_MODE;
-        va.va_mode = mode;
+        memset(vattr, 0, sizeof(*vattr));
+        vattr->va_mask = XFS_AT_TYPE|XFS_AT_MODE;
+        vattr->va_mode = mode;
 
         switch (mode & S_IFMT) {
         case S_IFCHR: case S_IFBLK: case S_IFIFO: case S_IFSOCK:
-                va.va_rdev = sysv_encode_dev(rdev);
-                va.va_mask |= XFS_AT_RDEV;
+                vattr->va_rdev = sysv_encode_dev(rdev);
+                vattr->va_mask |= XFS_AT_RDEV;
                 /*FALLTHROUGH*/
         case S_IFREG:
-                VOP_CREATE(dvp, dentry, &va, &vp, NULL, error);
+                VOP_CREATE(dvp, dentry, vattr, &vp, NULL, error);
                 break;
         case S_IFDIR:
-                VOP_MKDIR(dvp, dentry, &va, &vp, NULL, error);
+                VOP_MKDIR(dvp, dentry, vattr, &vp, NULL, error);
                 break;
         default:
                 error = EINVAL;
                 break;
         }
 
-        if (!error)
-        {
-                error = linvfs_init_security(vp, dir);
+        if (unlikely(!error)) {
+                error = __linvfs_init_security(vp, dir);
                 if (error)
-                        cleanup_inode(dvp, vp, dentry, mode);
+                        __linvfs_cleanup_inode(dvp, vp, dentry, mode);
         }
 
-        if (default_acl) {
+        if (unlikely(default_acl)) {
                 if (!error) {
-                        error = _ACL_INHERIT(vp, &va, default_acl);
-                        if (!error) 
+                        error = _ACL_INHERIT(vp, vattr, default_acl);
+                        if (!error)
                                 VMODIFY(vp);
                         else
-                                cleanup_inode(dvp, vp, dentry, mode);
+                                __linvfs_cleanup_inode(dvp, vp, dentry, mode);
                 }
                 _ACL_FREE(default_acl);
         }
 
-        if (!error) {
+        if (likely(!error)) {
                 ASSERT(vp);
                 ip = LINVFS_GET_IP(vp);
 
                 if (S_ISCHR(mode) || S_ISBLK(mode))
                         ip->i_rdev = rdev;
                 else if (S_ISDIR(mode))
-                        validate_fields(ip);
+                        __linvfs_validate_fields(ip, vattr);
                 d_instantiate(dentry, ip);
-                validate_fields(dir);
+                __linvfs_validate_fields(dir, vattr);
         }
+        kfree(vattr);
         return -error;
 }
 
@@ -423,22 +429,28 @@ linvfs_link(
         struct inode    *ip;    /* inode of guy being linked to */
         vnode_t         *tdvp;  /* target directory for new name/link */
         vnode_t         *vp;    /* vp of name being linked */
+        vattr_t         *vattr;
         int             error;
 
         ip = old_dentry->d_inode;       /* inode being linked to */
         if (S_ISDIR(ip->i_mode))
                 return -EPERM;
 
+        vattr = kmalloc(sizeof(*vattr), GFP_KERNEL);
+        if (unlikely(!vattr))
+                return -ENOMEM;
+
         tdvp = LINVFS_GET_VP(dir);
         vp = LINVFS_GET_VP(ip);
 
         VOP_LINK(tdvp, vp, dentry, NULL, error);
-        if (!error) {
+        if (likely(!error)) {
                 VMODIFY(tdvp);
                 VN_HOLD(vp);
-                validate_fields(ip);
+                __linvfs_validate_fields(ip, vattr);
                 d_instantiate(dentry, ip);
         }
+        kfree(vattr);
         return -error;
 }
 
@@ -449,17 +461,22 @@ linvfs_unlink(
 {
         struct inode    *inode;
         vnode_t         *dvp;   /* directory containing name to remove */
+        vattr_t         *vattr;
         int             error;
 
+        vattr = kmalloc(sizeof(*vattr), GFP_KERNEL);
+        if (unlikely(!vattr))
+                return -ENOMEM;
+
         inode = dentry->d_inode;
         dvp = LINVFS_GET_VP(dir);
 
         VOP_REMOVE(dvp, dentry, NULL, error);
-        if (!error) {
-                validate_fields(dir);   /* For size only */
-                validate_fields(inode);
+        if (likely(!error)) {
+                __linvfs_validate_fields(dir, vattr);   /* size needs update */
+                __linvfs_validate_fields(inode, vattr);
         }
-
+        kfree(vattr);
         return -error;
 }
 
@@ -470,7 +487,7 @@ linvfs_symlink(
         const char      *symname)
 {
         struct inode    *ip;
-        vattr_t         va;
+        vattr_t         *vattr;
         vnode_t         *dvp;   /* directory containing name of symlink */
         vnode_t         *cvp;   /* used to lookup symlink to put in dentry */
         int             error;
@@ -478,22 +495,27 @@ linvfs_symlink(
         dvp = LINVFS_GET_VP(dir);
         cvp = NULL;
 
-        memset(&va, 0, sizeof(va));
-        va.va_mode = S_IFLNK |
+        vattr = kmalloc(sizeof(*vattr), GFP_KERNEL);
+        if (unlikely(!vattr))
+                return -ENOMEM;
+
+        memset(vattr, 0, sizeof(*vattr));
+        vattr->va_mode = S_IFLNK |
                 (irix_symlink_mode ? 0777 & ~current->fs->umask : S_IRWXUGO);
-        va.va_mask = XFS_AT_TYPE|XFS_AT_MODE;
+        vattr->va_mask = XFS_AT_TYPE|XFS_AT_MODE;
 
         error = 0;
-        VOP_SYMLINK(dvp, dentry, &va, (char *)symname, &cvp, NULL, error);
+        VOP_SYMLINK(dvp, dentry, vattr, (char *)symname, &cvp, NULL, error);
         if (likely(!error && cvp)) {
-                error = linvfs_init_security(cvp, dir);
+                error = __linvfs_init_security(cvp, dir);
                 if (likely(!error)) {
                         ip = LINVFS_GET_IP(cvp);
                         d_instantiate(dentry, ip);
-                        validate_fields(dir);
-                        validate_fields(ip);
+                        __linvfs_validate_fields(dir, vattr);
+                        __linvfs_validate_fields(ip, vattr);
                 }
         }
+        kfree(vattr);
         return -error;
 }
 
@@ -504,13 +526,19 @@ linvfs_rmdir(
 {
         struct inode    *inode = dentry->d_inode;
         vnode_t         *dvp = LINVFS_GET_VP(dir);
+        vattr_t         *vattr;
         int             error;
 
+        vattr = kmalloc(sizeof(*vattr), GFP_KERNEL);
+        if (unlikely(!vattr))
+                return -ENOMEM;
+
         VOP_RMDIR(dvp, dentry, NULL, error);
-        if (!error) {
-                validate_fields(inode);
-                validate_fields(dir);
+        if (likely(!error)) {
+                __linvfs_validate_fields(inode, vattr);
+                __linvfs_validate_fields(dir, vattr);
         }
+        kfree(vattr);
         return -error;
 }
 
@@ -524,22 +552,26 @@ linvfs_rename(
         struct inode    *new_inode = ndentry->d_inode;
         vnode_t         *fvp;   /* from directory */
         vnode_t         *tvp;   /* target directory */
+        vattr_t         *vattr;
         int             error;
 
+        vattr = kmalloc(sizeof(*vattr), GFP_KERNEL);
+        if (unlikely(!vattr))
+                return -ENOMEM;
+
         fvp = LINVFS_GET_VP(odir);
         tvp = LINVFS_GET_VP(ndir);
 
         VOP_RENAME(fvp, odentry, tvp, ndentry, NULL, error);
-        if (error)
-                return -error;
-
-        if (new_inode)
-                validate_fields(new_inode);
-
-        validate_fields(odir);
-        if (ndir != odir)
-                validate_fields(ndir);
-        return 0;
+        if (likely(!error)) {
+                if (new_inode)
+                        __linvfs_validate_fields(new_inode, vattr);
+                __linvfs_validate_fields(odir, vattr);
+                if (ndir != odir)
+                        __linvfs_validate_fields(ndir, vattr);
+        }
+        kfree(vattr);
+        return -error;
 }
 
 /*
@@ -653,11 +685,10 @@ linvfs_setattr(
         struct inode    *inode = dentry->d_inode;
         unsigned int    ia_valid = attr->ia_valid;
         vnode_t         *vp = LINVFS_GET_VP(inode);
-        vattr_t         vattr;
+        vattr_t         vattr = { 0 };
         int             flags = 0;
         int             error;
 
-        memset(&vattr, 0, sizeof(vattr_t));
         if (ia_valid & ATTR_UID) {
                 vattr.va_mask |= XFS_AT_UID;
                 vattr.va_uid = attr->ia_uid;
@@ -699,10 +730,9 @@ linvfs_setattr(
 #endif
 
         VOP_SETATTR(vp, &vattr, flags, NULL, error);
-        if (error)
-                return -error;
-        vn_revalidate(vp);
-        return error;
+        if (likely(!error))
+                __vn_revalidate(vp, &vattr);
+        return -error;
 }
 
 STATIC void