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1There is a potential for deadlock when allocating a struct sk_buff for
2data that needs to be written out to aoe storage. If the data is
3being written from a dirty page in order to free that page, and if
4there are no other pages available, then deadlock may occur when a
5free page is needed for the sk_buff allocation. This situation has
6not been observed, but it would be nice to eliminate any potential for
7deadlock under memory pressure.
8
9Because ATA over Ethernet is not fragmented by the kernel's IP code,
10the destructore member of the struct sk_buff is available to the aoe
11driver. By using a mempool for allocating all but the first few
12sk_buffs, and by registering a destructor, we should be able to
13efficiently allocate sk_buffs without introducing any potential for
14deadlock.