--- IO-AIO/AIO.xs	2012/04/10 05:01:33	1.213
+++ IO-AIO/AIO.xs	2012/07/27 18:43:25	1.219
@@ -169,9 +169,9 @@
 #if HAVE_FIEMAP
   int count = req->int3;
 
-  /* heuristic: first try with 64 extents if we don't know how many, */
+  /* heuristic: first try with 72 extents if we don't know how many, */
   /* as most files have (hopefully) fewer than this many extents */
-  /* in fact, most should have <= 2, so maybe the 72 below is probably overkill */
+  /* in fact, most should have <= 2, so the 72 below is probably overkill */
   if (count < 0)
     count = 72; /* for what it's worth, 72 extents fit nicely into 4kb */
 
@@ -196,16 +196,23 @@
       if (req->int3 >= 0)
         break; /* when not autosizing we are done */
 
-      if (fiemap->fm_extents [fiemap->fm_mapped_extents - 1].fe_flags & FIEMAP_EXTENT_LAST)
-        break; /* autosizing successful, we are done */
+      if (fiemap->fm_mapped_extents < count)
+        /* either autosizing succeeded,
+         * or the file had no extents
+         * or we luckily had enough space */
+        break;
 
+      /* some kernels overwrite fm_length, so just reset everything */
+      fiemap->fm_start        = req->offs;
+      fiemap->fm_length       = req->size;
       fiemap->fm_flags        = req->int2;
       fiemap->fm_extent_count = 0;
 
       if (ioctl (req->int1, FS_IOC_FIEMAP, fiemap))
         return;
 
-      count = fiemap->fm_mapped_extents;
+      /* to work around a kernel bug, we allocate one more */
+      count = fiemap->fm_mapped_extents + 1;
 
       free (fiemap);
     }
@@ -985,6 +992,7 @@
     const_eio (SYNC_FILE_RANGE_WAIT_AFTER)
 
     const_eio (FALLOC_FL_KEEP_SIZE)
+    const_eio (FALLOC_FL_PUNCH_HOLE)
 
     const_eio (READDIR_DENTS)
     const_eio (READDIR_DIRS_FIRST)
@@ -1217,7 +1225,10 @@
           {
             /* read: check type and grow scalar as necessary */
             SvUPGRADE (data, SVt_PV);
-            svptr = SvGROW (data, len + dataoffset + 1);
+            if (SvLEN (data) >= SvCUR (data))
+              svptr = SvGROW (data, len + dataoffset + 1);
+            else if (SvCUR (data) < len + dataoffset)
+              croak ("length + dataoffset outside of scalar, and cannot grow");
           }
 
         {
@@ -1530,7 +1541,7 @@
 aio_fiemap (SV *fh, off_t start, SV *length, U32 flags, SV *count, SV *callback=&PL_sv_undef)
         PPCODE:
 {
-  	int fd = s_fileno_croak (fh, 0);
+	int fd = s_fileno_croak (fh, 0);
 	dREQ;
 
         req->type = EIO_CUSTOM;
@@ -1688,7 +1699,7 @@
         RETVAL
 
 void
-mmap (SV *scalar, size_t length, int prot, int flags, SV *fh, off_t offset = 0)
+mmap (SV *scalar, size_t length, int prot, int flags, SV *fh = &PL_sv_undef, off_t offset = 0)
 	PPCODE:
         sv_unmagic (scalar, MMAP_MAGIC);
 {
@@ -1731,7 +1742,7 @@
         CODE:
 {
 	STRLEN svlen;
-  	void *addr = SvPVbyte (scalar, svlen);
+	void *addr = SvPVbyte (scalar, svlen);
         size_t len = SvUV (length);
 
         if (offset < 0)