xfs: Update inode alloc comments

I found some out of date comments while studying the inode allocation
code, so I believe it's worth to have these comments updated.

It basically rewrites the comment regarding to "call_again" variable,
which is not used anymore, but instead, callers of xfs_ialloc() decides
if it needs to be called again relying only if ialloc_context is NULL or
not.

Also did some small changes in another comment that I thought to be
pertinent to the current behaviour of these functions and some alignment
on both comments.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

fs/xfs/xfs_ialloc.c

@@ -877,9 +877,9 @@ error0:
  * This function is designed to be called twice if it has to do an allocation
  * to make more free inodes.  On the first call, *IO_agbp should be set to NULL.
  * If an inode is available without having to performn an allocation, an inode
- * number is returned.  In this case, *IO_agbp would be NULL.  If an allocation
- * needes to be done, xfs_dialloc would return the current AGI buffer in
- * *IO_agbp.  The caller should then commit the current transaction, allocate a
+ * number is returned.  In this case, *IO_agbp is set to NULL.  If an allocation
+ * needs to be done, xfs_dialloc returns the current AGI buffer in *IO_agbp.
+ * The caller should then commit the current transaction, allocate a
  * new transaction, and call xfs_dialloc() again, passing in the previous value
  * of *IO_agbp.  IO_agbp should be held across the transactions. Since the AGI
  * buffer is locked across the two calls, the second call is guaranteed to have

fs/xfs/xfs_inode.c

@@ -1104,16 +1104,16 @@ xfs_iread_extents(
  * set according to the contents of the given cred structure.
  *
  * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
- * has a free inode available, call xfs_iget()
- * to obtain the in-core version of the allocated inode.  Finally,
- * fill in the inode and log its initial contents.  In this case,
- * ialloc_context would be set to NULL and call_again set to false.
+ * has a free inode available, call xfs_iget() to obtain the in-core
+ * version of the allocated inode.  Finally, fill in the inode and
+ * log its initial contents.  In this case, ialloc_context would be
+ * set to NULL.
  *
- * If xfs_dialloc() does not have an available inode,
- * it will replenish its supply by doing an allocation. Since we can
- * only do one allocation within a transaction without deadlocks, we
- * must commit the current transaction before returning the inode itself.
- * In this case, therefore, we will set call_again to true and return.
+ * If xfs_dialloc() does not have an available inode, it will replenish
+ * its supply by doing an allocation. Since we can only do one
+ * allocation within a transaction without deadlocks, we must commit
+ * the current transaction before returning the inode itself.
+ * In this case, therefore, we will set ialloc_context and return.
  * The caller should then commit the current transaction, start a new
  * transaction, and call xfs_ialloc() again to actually get the inode.
  *