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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2009-01-15 06:05:05 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-01-15 06:05:05 +0100 |
| commit | 937f1ba56b4be37d9e2ad77412f95048662058d2 (patch) | |
| tree | 154e0c5ce11b5afe25816d667c76b19ac679d530 /net/core | |
| parent | drivers/net/irda/irda-usb.c: fix buffer overflow (diff) | |
| download | linux-937f1ba56b4be37d9e2ad77412f95048662058d2.tar.xz linux-937f1ba56b4be37d9e2ad77412f95048662058d2.zip | |
net: Add init_dummy_netdev() and fix EMAC driver using it
This adds an init_dummy_netdev() function that gets a network device
structure (allocation and lifetime entirely under caller's control) and
initialize the minimum amount of fields so it can be used to schedule
NAPI polls without registering a full blown interface. This is to be
used by drivers that need to tie several hardware interfaces to a single
NAPI poll scheduler due to HW limitations.
It also updates the ibm_newemac driver to use that, this fixing the
oops on 2.6.29 due to passing NULL as "dev" to netif_napi_add()
Symbol is exported GPL only a I don't think we want binary drivers doing
that sort of acrobatics (if we want them at all).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/dev.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 60377b6c0a80..8d675975d85b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4431,6 +4431,45 @@ err_uninit: } /** + * init_dummy_netdev - init a dummy network device for NAPI + * @dev: device to init + * + * This takes a network device structure and initialize the minimum + * amount of fields so it can be used to schedule NAPI polls without + * registering a full blown interface. This is to be used by drivers + * that need to tie several hardware interfaces to a single NAPI + * poll scheduler due to HW limitations. + */ +int init_dummy_netdev(struct net_device *dev) +{ + /* Clear everything. Note we don't initialize spinlocks + * are they aren't supposed to be taken by any of the + * NAPI code and this dummy netdev is supposed to be + * only ever used for NAPI polls + */ + memset(dev, 0, sizeof(struct net_device)); + + /* make sure we BUG if trying to hit standard + * register/unregister code path + */ + dev->reg_state = NETREG_DUMMY; + + /* initialize the ref count */ + atomic_set(&dev->refcnt, 1); + + /* NAPI wants this */ + INIT_LIST_HEAD(&dev->napi_list); + + /* a dummy interface is started by default */ + set_bit(__LINK_STATE_PRESENT, &dev->state); + set_bit(__LINK_STATE_START, &dev->state); + + return 0; +} +EXPORT_SYMBOL_GPL(init_dummy_netdev); + + +/** * register_netdev - register a network device * @dev: device to register * |