ocfs2: Wrap calculation of name+value pair size.

An ocfs2 xattr entry stores the text name and value as a pair in the
storage area.  Obviously names and values can be variable-sized.  If a
value is too large for the entry storage, a tree root is stored instead.
The name+value pair is also padded.

Because of this, there are a million places in the code that do:

	if (needs_external_tree(value_size)
		namevalue_size = pad(name_size) + tree_root_size;
	else
		namevalue_size = pad(name_size) + pad(value_size);

Let's create some convenience functions to make the code more readable.
There are three forms.  The first takes the raw sizes.  The second takes
an ocfs2_xattr_info structure.  The third takes an existing
ocfs2_xattr_entry.

Signed-off-by: Joel Becker <joel.becker@oracle.com>

1 files changed, 65 insertions, 105 deletions

diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 68126adbf311..064ec6d6c23c 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -183,6 +183,33 @@ struct ocfs2_xa_loc {
         const struct ocfs2_xa_loc_operations *xl_ops;
 };
 
+/*
+ * Convenience functions to calculate how much space is needed for a
+ * given name+value pair
+ */
+static int namevalue_size(int name_len, uint64_t value_len)
+{
+        if (value_len > OCFS2_XATTR_INLINE_SIZE)
+                return OCFS2_XATTR_SIZE(name_len) + OCFS2_XATTR_ROOT_SIZE;
+        else
+                return OCFS2_XATTR_SIZE(name_len) + OCFS2_XATTR_SIZE(value_len);
+}
+
+static int namevalue_size_xi(struct ocfs2_xattr_info *xi)
+{
+        return namevalue_size(xi->xi_name_len, xi->xi_value_len);
+}
+
+static int namevalue_size_xe(struct ocfs2_xattr_entry *xe)
+{
+        u64 value_len = le64_to_cpu(xe->xe_value_size);
+
+        BUG_ON((value_len > OCFS2_XATTR_INLINE_SIZE) &&
+               ocfs2_xattr_is_local(xe));
+        return namevalue_size(xe->xe_name_len, value_len);
+}
+
+
 static int ocfs2_xattr_bucket_get_name_value(struct super_block *sb,
                                              struct ocfs2_xattr_header *xh,
                                              int index,
@@ -529,15 +556,20 @@ static void ocfs2_xattr_hash_entry(struct inode *inode,
 
 static int ocfs2_xattr_entry_real_size(int name_len, size_t value_len)
 {
-        int size = 0;
+        return namevalue_size(name_len, value_len) +
+                sizeof(struct ocfs2_xattr_entry);
+}
 
-        if (value_len <= OCFS2_XATTR_INLINE_SIZE)
-                size = OCFS2_XATTR_SIZE(name_len) + OCFS2_XATTR_SIZE(value_len);
-        else
-                size = OCFS2_XATTR_SIZE(name_len) + OCFS2_XATTR_ROOT_SIZE;
-        size += sizeof(struct ocfs2_xattr_entry);
+static int ocfs2_xi_entry_usage(struct ocfs2_xattr_info *xi)
+{
+        return namevalue_size_xi(xi) +
+                sizeof(struct ocfs2_xattr_entry);
+}
 
-        return size;
+static int ocfs2_xe_entry_usage(struct ocfs2_xattr_entry *xe)
+{
+        return namevalue_size_xe(xe) +
+                sizeof(struct ocfs2_xattr_entry);
 }
 
 int ocfs2_calc_security_init(struct inode *dir,
@@ -1363,8 +1395,7 @@ static int ocfs2_xattr_cleanup(struct inode *inode,
 {
         int ret = 0;
         void *val = xs->base + offs;
-        size_t size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                OCFS2_XATTR_ROOT_SIZE;
+        size_t size = namevalue_size_xi(xi);
 
         ret = vb->vb_access(handle, INODE_CACHE(inode), vb->vb_bh,
                             OCFS2_JOURNAL_ACCESS_WRITE);
@@ -1430,8 +1461,7 @@ static int ocfs2_xattr_set_value_outside(struct inode *inode,
 {
         void *val = xs->base + offs;
         struct ocfs2_xattr_value_root *xv = NULL;
-        size_t size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                OCFS2_XATTR_ROOT_SIZE;
+        size_t size = namevalue_size_xi(xi);
         int ret = 0;
 
         memset(val, 0, size);
@@ -1490,15 +1520,10 @@ static void ocfs2_xa_block_wipe_namevalue(struct ocfs2_xa_loc *loc)
         int namevalue_offset, first_namevalue_offset, namevalue_size;
         struct ocfs2_xattr_entry *entry = loc->xl_entry;
         struct ocfs2_xattr_header *xh = loc->xl_header;
-        u64 value_size = le64_to_cpu(entry->xe_value_size);
         int count = le16_to_cpu(xh->xh_count);
 
         namevalue_offset = le16_to_cpu(entry->xe_name_offset);
-        namevalue_size = OCFS2_XATTR_SIZE(entry->xe_name_len);
-        if (value_size > OCFS2_XATTR_INLINE_SIZE)
-                namevalue_size += OCFS2_XATTR_ROOT_SIZE;
-        else
-                namevalue_size += OCFS2_XATTR_SIZE(value_size);
+        namevalue_size = namevalue_size_xe(entry);
 
         for (i = 0, first_namevalue_offset = loc->xl_size;
              i < count; i++) {
@@ -1553,17 +1578,8 @@ static void *ocfs2_xa_bucket_offset_pointer(struct ocfs2_xa_loc *loc,
 
 static void ocfs2_xa_bucket_wipe_namevalue(struct ocfs2_xa_loc *loc)
 {
-        int namevalue_size;
-        struct ocfs2_xattr_entry *entry = loc->xl_entry;
-        u64 value_size = le64_to_cpu(entry->xe_value_size);
-
-        namevalue_size = OCFS2_XATTR_SIZE(entry->xe_name_len);
-        if (value_size > OCFS2_XATTR_INLINE_SIZE)
-                namevalue_size += OCFS2_XATTR_ROOT_SIZE;
-        else
-                namevalue_size += OCFS2_XATTR_SIZE(value_size);
-
-        le16_add_cpu(&loc->xl_header->xh_name_value_len, -namevalue_size);
+        le16_add_cpu(&loc->xl_header->xh_name_value_len,
+                     -namevalue_size_xe(loc->xl_entry));
 }
 
 /* Operations for xattrs stored in buckets. */
@@ -1683,16 +1699,8 @@ static void ocfs2_xattr_set_entry_local(struct inode *inode,
                 offs = le16_to_cpu(xs->here->xe_name_offset);
                 val = xs->base + offs;
 
-                if (le64_to_cpu(xs->here->xe_value_size) >
-                    OCFS2_XATTR_INLINE_SIZE)
-                        size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                                OCFS2_XATTR_ROOT_SIZE;
-                else
-                        size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                        OCFS2_XATTR_SIZE(le64_to_cpu(xs->here->xe_value_size));
-
-                if (xi->xi_value && size == OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                                OCFS2_XATTR_SIZE(xi->xi_value_len)) {
+                size = namevalue_size_xe(xs->here);
+                if (xi->xi_value && (size == namevalue_size_xi(xi))) {
                         /* The old and the new value have the
                            same size. Just replace the value. */
                         ocfs2_xattr_set_local(xs->here, 1);
@@ -1716,8 +1724,7 @@ static void ocfs2_xattr_set_entry_local(struct inode *inode,
         }
         if (xi->xi_value) {
                 /* Insert the new name+value. */
-                size_t size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                                OCFS2_XATTR_SIZE(xi->xi_value_len);
+                size_t size = namevalue_size_xi(xi);
                 void *val = xs->base + min_offs - size;
 
                 xs->here->xe_name_offset = cpu_to_le16(min_offs - size);
@@ -1788,41 +1795,25 @@ static int ocfs2_xattr_set_entry(struct inode *inode,
         if (free < 0)
                 return -EIO;
 
-        if (!xs->not_found) {
-                size_t size = 0;
-                if (ocfs2_xattr_is_local(xs->here))
-                        size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                        OCFS2_XATTR_SIZE(le64_to_cpu(xs->here->xe_value_size));
-                else
-                        size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                                OCFS2_XATTR_ROOT_SIZE;
-                free += (size + sizeof(struct ocfs2_xattr_entry));
-        }
+        if (!xs->not_found)
+                free += ocfs2_xe_entry_usage(xs->here);
+
         /* Check free space in inode or block */
-        if (xi->xi_value && xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE) {
-                if (free < sizeof(struct ocfs2_xattr_entry) +
-                           OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                           OCFS2_XATTR_ROOT_SIZE) {
+        if (xi->xi_value) {
+                if (free < ocfs2_xi_entry_usage(xi)) {
                         ret = -ENOSPC;
                         goto out;
                 }
-                size_l = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                        OCFS2_XATTR_ROOT_SIZE;
-                xi_l.xi_value = (void *)&def_xv;
-                xi_l.xi_value_len = OCFS2_XATTR_ROOT_SIZE;
-        } else if (xi->xi_value) {
-                if (free < sizeof(struct ocfs2_xattr_entry) +
-                           OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                           OCFS2_XATTR_SIZE(xi->xi_value_len)) {
-                        ret = -ENOSPC;
-                        goto out;
+                if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE) {
+                        size_l = namevalue_size_xi(xi);
+                        xi_l.xi_value = (void *)&def_xv;
+                        xi_l.xi_value_len = OCFS2_XATTR_ROOT_SIZE;
                 }
         }
 
         if (!xs->not_found) {
                 /* For existing extended attribute */
-                size_t size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                        OCFS2_XATTR_SIZE(le64_to_cpu(xs->here->xe_value_size));
+                size_t size = namevalue_size_xe(xs->here);
                 size_t offs = le16_to_cpu(xs->here->xe_name_offset);
                 void *val = xs->base + offs;
 
@@ -2589,7 +2580,6 @@ static int ocfs2_xattr_can_be_in_inode(struct inode *inode,
                                        struct ocfs2_xattr_info *xi,
                                        struct ocfs2_xattr_search *xs)
 {
-        u64 value_size;
         struct ocfs2_xattr_entry *last;
         int free, i;
         size_t min_offs = xs->end - xs->base;
@@ -2612,13 +2602,7 @@ static int ocfs2_xattr_can_be_in_inode(struct inode *inode,
 
         BUG_ON(!xs->not_found);
 
-        if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE)
-                value_size = OCFS2_XATTR_ROOT_SIZE;
-        else
-                value_size = OCFS2_XATTR_SIZE(xi->xi_value_len);
-
-        if (free >= sizeof(struct ocfs2_xattr_entry) +
-                   OCFS2_XATTR_SIZE(xi->xi_name_len) + value_size)
+        if (free >= (sizeof(struct ocfs2_xattr_entry) + namevalue_size_xi(xi)))
                 return 1;
 
         return 0;
@@ -3980,7 +3964,7 @@ static int ocfs2_defrag_xattr_bucket(struct inode *inode,
                                      struct ocfs2_xattr_bucket *bucket)
 {
         int ret, i;
-        size_t end, offset, len, value_len;
+        size_t end, offset, len;
         struct ocfs2_xattr_header *xh;
         char *entries, *buf, *bucket_buf = NULL;
         u64 blkno = bucket_blkno(bucket);
@@ -4034,12 +4018,7 @@ static int ocfs2_defrag_xattr_bucket(struct inode *inode,
         end = OCFS2_XATTR_BUCKET_SIZE;
         for (i = 0; i < le16_to_cpu(xh->xh_count); i++, xe++) {
                 offset = le16_to_cpu(xe->xe_name_offset);
-                if (ocfs2_xattr_is_local(xe))
-                        value_len = OCFS2_XATTR_SIZE(
-                                        le64_to_cpu(xe->xe_value_size));
-                else
-                        value_len = OCFS2_XATTR_ROOT_SIZE;
-                len = OCFS2_XATTR_SIZE(xe->xe_name_len) + value_len;
+                len = namevalue_size_xe(xe);
 
                 /*
                  * We must make sure that the name/value pair
@@ -4228,7 +4207,7 @@ static int ocfs2_divide_xattr_bucket(struct inode *inode,
                                     int new_bucket_head)
 {
         int ret, i;
-        int count, start, len, name_value_len = 0, xe_len, name_offset = 0;
+        int count, start, len, name_value_len = 0, name_offset = 0;
         struct ocfs2_xattr_bucket *s_bucket = NULL, *t_bucket = NULL;
         struct ocfs2_xattr_header *xh;
         struct ocfs2_xattr_entry *xe;
@@ -4319,13 +4298,7 @@ static int ocfs2_divide_xattr_bucket(struct inode *inode,
         name_value_len = 0;
         for (i = 0; i < start; i++) {
                 xe = &xh->xh_entries[i];
-                xe_len = OCFS2_XATTR_SIZE(xe->xe_name_len);
-                if (ocfs2_xattr_is_local(xe))
-                        xe_len +=
-                           OCFS2_XATTR_SIZE(le64_to_cpu(xe->xe_value_size));
-                else
-                        xe_len += OCFS2_XATTR_ROOT_SIZE;
-                name_value_len += xe_len;
+                name_value_len += namevalue_size_xe(xe);
                 if (le16_to_cpu(xe->xe_name_offset) < name_offset)
                         name_offset = le16_to_cpu(xe->xe_name_offset);
         }
@@ -4355,12 +4328,6 @@ static int ocfs2_divide_xattr_bucket(struct inode *inode,
         xh->xh_free_start = cpu_to_le16(OCFS2_XATTR_BUCKET_SIZE);
         for (i = 0; i < le16_to_cpu(xh->xh_count); i++) {
                 xe = &xh->xh_entries[i];
-                xe_len = OCFS2_XATTR_SIZE(xe->xe_name_len);
-                if (ocfs2_xattr_is_local(xe))
-                        xe_len +=
-                           OCFS2_XATTR_SIZE(le64_to_cpu(xe->xe_value_size));
-                else
-                        xe_len += OCFS2_XATTR_ROOT_SIZE;
                 if (le16_to_cpu(xe->xe_name_offset) <
                     le16_to_cpu(xh->xh_free_start))
                         xh->xh_free_start = xe->xe_name_offset;
@@ -4997,12 +4964,7 @@ static void ocfs2_xattr_set_entry_normal(struct inode *inode,
         if (!xs->not_found) {
                 xe = xs->here;
                 offs = le16_to_cpu(xe->xe_name_offset);
-                if (ocfs2_xattr_is_local(xe))
-                        size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                        OCFS2_XATTR_SIZE(le64_to_cpu(xe->xe_value_size));
-                else
-                        size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                        OCFS2_XATTR_SIZE(OCFS2_XATTR_ROOT_SIZE);
+                size = namevalue_size_xe(xe);
 
                 /*
                  * If the new value will be stored outside, xi->xi_value has
@@ -5011,8 +4973,7 @@ static void ocfs2_xattr_set_entry_normal(struct inode *inode,
                  * new_size safely here.
                  * See ocfs2_xattr_set_in_bucket.
                  */
-                new_size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                           OCFS2_XATTR_SIZE(xi->xi_value_len);
+                new_size = namevalue_size_xi(xi);
 
                 if (xi->xi_value) {
                         ocfs2_xa_wipe_namevalue(&loc);
@@ -5078,8 +5039,7 @@ static void ocfs2_xattr_set_entry_normal(struct inode *inode,
 
 set_new_name_value:
         /* Insert the new name+value. */
-        size = OCFS2_XATTR_SIZE(xi->xi_name_len) +
-                OCFS2_XATTR_SIZE(xi->xi_value_len);
+        size = namevalue_size_xi(xi);
 
         /*
          * We must make sure that the name/value pair