jffs2 sumtool bug ?

Matthieu CASTET matthieu.castet at parrot.com
Wed May 23 04:10:06 EDT 2007


In sumtool, in pad_block_if_less_than, we pad and write to a new 
eraseblock if "(data_ofs + req > erase_block_size - datasize)".
But datasize = req + the size of the summary node.

So we pad and write to a new eraseblock if there is not the space for 
the summary node and (the node we are wanting to write) * 2.

Why the condition isn't "(data_ofs > erase_block_size - datasize)" ?



PS : about summary, could the sumtool change the order of the nodes to 
avoid to waste too much space. For example if the eraseblock is 16KB and 
we have 4 nodes of 4KB. Sumtool will put in the first eraseblock 3 
nodes, 4KB will be wasted for the sumary node. In this wasted 4KB, we 
could have put smaller nodes.

PS2 : How the kernel implementation does ? Does it try to minimize 
summary overhead, by managing to minimize the summary node size ?

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