From b53f35a8093e6aed7e8e880eaa0b89a3d2fdfb0a Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Tue, 16 Oct 2007 01:27:31 -0700 Subject: uml: network driver MTU cleanups A bunch of MTU-related cleanups in the network code. First, there is the addition of the notion of a maximally-sized packet, which is the MTU plus headers. This is used to size the skb that will receive a packet. This allows ether_adjust_skb to go away, as it was used to resize the skb after it was allocated. Since the skb passed into the low-level read routine is no longer resized, and possibly reallocated, there, they (and the write routines) don't need to get an sk_buff **. They just need the sk_buff * now. The callers of ether_adjust_skb still need to do the skb_put, so that's now inlined. The MAX_PACKET definitions in most of the drivers are gone. The set_mtu methods were all the same and did nothing, so they can be removed. The ethertap driver had a typo which doubled the size of the packet rather than adding two bytes to it. It also wasn't defining its setup_size, causing a zero-byte kmalloc and crash when the invalid pointer returned from kmalloc was dereferenced. Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/daemon_kern.c | 15 +++++---------- arch/um/drivers/daemon_user.c | 11 ++--------- arch/um/drivers/mcast_kern.c | 13 +++++-------- arch/um/drivers/mcast_user.c | 11 ++--------- arch/um/drivers/net_kern.c | 42 ++++++++---------------------------------- arch/um/drivers/pcap_kern.c | 13 ++++--------- arch/um/drivers/pcap_user.c | 9 ++++----- arch/um/drivers/slip_kern.c | 10 ++++------ arch/um/drivers/slip_user.c | 9 ++------- arch/um/drivers/slirp_kern.c | 14 ++++++-------- arch/um/drivers/slirp_user.c | 9 ++------- arch/um/drivers/vde_kern.c | 19 +++++++------------ arch/um/drivers/vde_user.c | 11 ++--------- 13 files changed, 53 insertions(+), 133 deletions(-) (limited to 'arch/um/drivers') diff --git a/arch/um/drivers/daemon_kern.c b/arch/um/drivers/daemon_kern.c index ac507bb87fea..d53ff52bb404 100644 --- a/arch/um/drivers/daemon_kern.c +++ b/arch/um/drivers/daemon_kern.c @@ -39,20 +39,15 @@ static void daemon_init(struct net_device *dev, void *data) printk("\n"); } -static int daemon_read(int fd, struct sk_buff **skb, - struct uml_net_private *lp) +static int daemon_read(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER); - if (*skb == NULL) - return -ENOMEM; - return net_recvfrom(fd, skb_mac_header(*skb), - (*skb)->dev->mtu + ETH_HEADER_OTHER); + return net_recvfrom(fd, skb_mac_header(skb), + skb->dev->mtu + ETH_HEADER_OTHER); } -static int daemon_write(int fd, struct sk_buff **skb, - struct uml_net_private *lp) +static int daemon_write(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - return daemon_user_write(fd, (*skb)->data, (*skb)->len, + return daemon_user_write(fd, skb->data, skb->len, (struct daemon_data *) &lp->user); } diff --git a/arch/um/drivers/daemon_user.c b/arch/um/drivers/daemon_user.c index 90983d480ac6..f23c109a055c 100644 --- a/arch/um/drivers/daemon_user.c +++ b/arch/um/drivers/daemon_user.c @@ -19,8 +19,6 @@ #include "um_malloc.h" #include "user.h" -#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER) - enum request_type { REQ_NEW_CONTROL }; #define SWITCH_MAGIC 0xfeedface @@ -184,18 +182,13 @@ int daemon_user_write(int fd, void *buf, int len, struct daemon_data *pri) return net_sendto(fd, buf, len, data_addr, sizeof(*data_addr)); } -static int daemon_set_mtu(int mtu, void *data) -{ - return mtu; -} - const struct net_user_info daemon_user_info = { .init = daemon_user_init, .open = daemon_open, .close = NULL, .remove = daemon_remove, - .set_mtu = daemon_set_mtu, .add_address = NULL, .delete_address = NULL, - .max_packet = MAX_PACKET - ETH_HEADER_OTHER + .mtu = ETH_MAX_PACKET, + .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER, }; diff --git a/arch/um/drivers/mcast_kern.c b/arch/um/drivers/mcast_kern.c index 5027b870d11d..822092f149be 100644 --- a/arch/um/drivers/mcast_kern.c +++ b/arch/um/drivers/mcast_kern.c @@ -39,18 +39,15 @@ static void mcast_init(struct net_device *dev, void *data) dpri->addr, dpri->port, dpri->ttl); } -static int mcast_read(int fd, struct sk_buff **skb, struct uml_net_private *lp) +static int mcast_read(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER); - if (*skb == NULL) - return -ENOMEM; - return net_recvfrom(fd, skb_mac_header(*skb), - (*skb)->dev->mtu + ETH_HEADER_OTHER); + return net_recvfrom(fd, skb_mac_header(skb), + skb->dev->mtu + ETH_HEADER_OTHER); } -static int mcast_write(int fd, struct sk_buff **skb, struct uml_net_private *lp) +static int mcast_write(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - return mcast_user_write(fd, (*skb)->data, (*skb)->len, + return mcast_user_write(fd, skb->data, skb->len, (struct mcast_data *) &lp->user); } diff --git a/arch/um/drivers/mcast_user.c b/arch/um/drivers/mcast_user.c index e427b5322a36..5f647d7a7292 100644 --- a/arch/um/drivers/mcast_user.c +++ b/arch/um/drivers/mcast_user.c @@ -20,8 +20,6 @@ #include "um_malloc.h" #include "user.h" -#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER) - static struct sockaddr_in *new_addr(char *addr, unsigned short port) { struct sockaddr_in *sin; @@ -154,18 +152,13 @@ int mcast_user_write(int fd, void *buf, int len, struct mcast_data *pri) return net_sendto(fd, buf, len, data_addr, sizeof(*data_addr)); } -static int mcast_set_mtu(int mtu, void *data) -{ - return mtu; -} - const struct net_user_info mcast_user_info = { .init = mcast_user_init, .open = mcast_open, .close = mcast_close, .remove = mcast_remove, - .set_mtu = mcast_set_mtu, .add_address = NULL, .delete_address = NULL, - .max_packet = MAX_PACKET - ETH_HEADER_OTHER + .mtu = ETH_MAX_PACKET, + .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER, }; diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c index b097a24c1496..59811cc880e0 100644 --- a/arch/um/drivers/net_kern.c +++ b/arch/um/drivers/net_kern.c @@ -41,16 +41,16 @@ static int uml_net_rx(struct net_device *dev) struct sk_buff *skb; /* If we can't allocate memory, try again next round. */ - skb = dev_alloc_skb(dev->mtu); + skb = dev_alloc_skb(lp->max_packet); if (skb == NULL) { lp->stats.rx_dropped++; return 0; } skb->dev = dev; - skb_put(skb, dev->mtu); + skb_put(skb, lp->max_packet); skb_reset_mac_header(skb); - pkt_len = (*lp->read)(lp->fd, &skb, lp); + pkt_len = (*lp->read)(lp->fd, skb, lp); if (pkt_len > 0) { skb_trim(skb, pkt_len); @@ -178,7 +178,7 @@ static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev) spin_lock_irqsave(&lp->lock, flags); - len = (*lp->write)(lp->fd, &skb, lp); + len = (*lp->write)(lp->fd, skb, lp); if (len == skb->len) { lp->stats.tx_packets++; @@ -240,22 +240,9 @@ static int uml_net_set_mac(struct net_device *dev, void *addr) static int uml_net_change_mtu(struct net_device *dev, int new_mtu) { - struct uml_net_private *lp = dev->priv; - int err = 0; - - spin_lock_irq(&lp->lock); - - new_mtu = (*lp->set_mtu)(new_mtu, &lp->user); - if (new_mtu < 0) { - err = new_mtu; - goto out; - } - dev->mtu = new_mtu; - out: - spin_unlock_irq(&lp->lock); - return err; + return 0; } static void uml_net_get_drvinfo(struct net_device *dev, @@ -427,6 +414,7 @@ static void eth_configure(int n, void *init, char *mac, .dev = dev, .fd = -1, .mac = { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0}, + .max_packet = transport->user->max_packet, .protocol = transport->kern->protocol, .open = transport->user->open, .close = transport->user->close, @@ -434,8 +422,7 @@ static void eth_configure(int n, void *init, char *mac, .read = transport->kern->read, .write = transport->kern->write, .add_address = transport->user->add_address, - .delete_address = transport->user->delete_address, - .set_mtu = transport->user->set_mtu }); + .delete_address = transport->user->delete_address }); init_timer(&lp->tl); spin_lock_init(&lp->lock); @@ -447,7 +434,7 @@ static void eth_configure(int n, void *init, char *mac, goto out_unregister; set_ether_mac(dev, device->mac); - dev->mtu = transport->user->max_packet; + dev->mtu = transport->user->mtu; dev->open = uml_net_open; dev->hard_start_xmit = uml_net_start_xmit; dev->stop = uml_net_close; @@ -807,19 +794,6 @@ static void close_devices(void) __uml_exitcall(close_devices); -struct sk_buff *ether_adjust_skb(struct sk_buff *skb, int extra) -{ - if ((skb != NULL) && (skb_tailroom(skb) < extra)) { - struct sk_buff *skb2; - - skb2 = skb_copy_expand(skb, 0, extra, GFP_ATOMIC); - dev_kfree_skb(skb); - skb = skb2; - } - if (skb != NULL) skb_put(skb, extra); - return skb; -} - void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *, void *), void *arg) diff --git a/arch/um/drivers/pcap_kern.c b/arch/um/drivers/pcap_kern.c index da0403efbc0d..3a750dd39be1 100644 --- a/arch/um/drivers/pcap_kern.c +++ b/arch/um/drivers/pcap_kern.c @@ -31,19 +31,14 @@ void pcap_init(struct net_device *dev, void *data) printk("pcap backend, host interface %s\n", ppri->host_if); } -static int pcap_read(int fd, struct sk_buff **skb, - struct uml_net_private *lp) +static int pcap_read(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER); - if (*skb == NULL) - return -ENOMEM; - - return pcap_user_read(fd, skb_mac_header(*skb), - (*skb)->dev->mtu + ETH_HEADER_OTHER, + return pcap_user_read(fd, skb_mac_header(skb), + skb->dev->mtu + ETH_HEADER_OTHER, (struct pcap_data *) &lp->user); } -static int pcap_write(int fd, struct sk_buff **skb, struct uml_net_private *lp) +static int pcap_write(int fd, struct sk_buff *skb, struct uml_net_private *lp) { return -EPERM; } diff --git a/arch/um/drivers/pcap_user.c b/arch/um/drivers/pcap_user.c index cf996b82af56..e9809356c530 100644 --- a/arch/um/drivers/pcap_user.c +++ b/arch/um/drivers/pcap_user.c @@ -13,8 +13,6 @@ #include "um_malloc.h" #include "user.h" -#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER) - #define PCAP_FD(p) (*(int *)(p)) static int pcap_user_init(void *data, void *dev) @@ -23,7 +21,8 @@ static int pcap_user_init(void *data, void *dev) pcap_t *p; char errors[PCAP_ERRBUF_SIZE]; - p = pcap_open_live(pri->host_if, MAX_PACKET, pri->promisc, 0, errors); + p = pcap_open_live(pri->host_if, ETH_MAX_PACKET + ETH_HEADER_OTHER, + pri->promisc, 0, errors); if (p == NULL) { printk(UM_KERN_ERR "pcap_user_init : pcap_open_live failed - " "'%s'\n", errors); @@ -133,8 +132,8 @@ const struct net_user_info pcap_user_info = { .open = pcap_open, .close = NULL, .remove = pcap_remove, - .set_mtu = NULL, .add_address = NULL, .delete_address = NULL, - .max_packet = MAX_PACKET - ETH_HEADER_OTHER + .mtu = ETH_MAX_PACKET, + .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER, }; diff --git a/arch/um/drivers/slip_kern.c b/arch/um/drivers/slip_kern.c index 05ed351de6b5..ae67e7158e71 100644 --- a/arch/um/drivers/slip_kern.c +++ b/arch/um/drivers/slip_kern.c @@ -47,17 +47,15 @@ static unsigned short slip_protocol(struct sk_buff *skbuff) return htons(ETH_P_IP); } -static int slip_read(int fd, struct sk_buff **skb, - struct uml_net_private *lp) +static int slip_read(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - return slip_user_read(fd, skb_mac_header(*skb), (*skb)->dev->mtu, + return slip_user_read(fd, skb_mac_header(skb), skb->dev->mtu, (struct slip_data *) &lp->user); } -static int slip_write(int fd, struct sk_buff **skb, - struct uml_net_private *lp) +static int slip_write(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - return slip_user_write(fd, (*skb)->data, (*skb)->len, + return slip_user_write(fd, skb->data, skb->len, (struct slip_data *) &lp->user); } diff --git a/arch/um/drivers/slip_user.c b/arch/um/drivers/slip_user.c index d78f324e7298..5f06204d6871 100644 --- a/arch/um/drivers/slip_user.c +++ b/arch/um/drivers/slip_user.c @@ -230,11 +230,6 @@ int slip_user_write(int fd, void *buf, int len, struct slip_data *pri) return slip_proto_write(fd, buf, len, &pri->slip); } -static int slip_set_mtu(int mtu, void *data) -{ - return mtu; -} - static void slip_add_addr(unsigned char *addr, unsigned char *netmask, void *data) { @@ -260,8 +255,8 @@ const struct net_user_info slip_user_info = { .open = slip_open, .close = slip_close, .remove = NULL, - .set_mtu = slip_set_mtu, .add_address = slip_add_addr, .delete_address = slip_del_addr, - .max_packet = BUF_SIZE + .mtu = BUF_SIZE, + .max_packet = BUF_SIZE, }; diff --git a/arch/um/drivers/slirp_kern.c b/arch/um/drivers/slirp_kern.c index b208d5e4a405..240ee650865d 100644 --- a/arch/um/drivers/slirp_kern.c +++ b/arch/um/drivers/slirp_kern.c @@ -52,18 +52,16 @@ static unsigned short slirp_protocol(struct sk_buff *skbuff) return htons(ETH_P_IP); } -static int slirp_read(int fd, struct sk_buff **skb, - struct uml_net_private *lp) +static int slirp_read(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - return slirp_user_read(fd, skb_mac_header(*skb), (*skb)->dev->mtu, - (struct slirp_data *) &lp->user); + return slirp_user_read(fd, skb_mac_header(skb), skb->dev->mtu, + (struct slirp_data *) &lp->user); } -static int slirp_write(int fd, struct sk_buff **skb, - struct uml_net_private *lp) +static int slirp_write(int fd, struct sk_buff *skb, struct uml_net_private *lp) { - return slirp_user_write(fd, (*skb)->data, (*skb)->len, - (struct slirp_data *) &lp->user); + return slirp_user_write(fd, skb->data, skb->len, + (struct slirp_data *) &lp->user); } const struct net_kern_info slirp_kern_info = { diff --git a/arch/um/drivers/slirp_user.c b/arch/um/drivers/slirp_user.c index a4755bc33e1e..1865089ff41a 100644 --- a/arch/um/drivers/slirp_user.c +++ b/arch/um/drivers/slirp_user.c @@ -124,18 +124,13 @@ int slirp_user_write(int fd, void *buf, int len, struct slirp_data *pri) return slip_proto_write(fd, buf, len, &pri->slip); } -static int slirp_set_mtu(int mtu, void *data) -{ - return mtu; -} - const struct net_user_info slirp_user_info = { .init = slirp_user_init, .open = slirp_open, .close = slirp_close, .remove = NULL, - .set_mtu = slirp_set_mtu, .add_address = NULL, .delete_address = NULL, - .max_packet = BUF_SIZE + .mtu = BUF_SIZE, + .max_packet = BUF_SIZE, }; diff --git a/arch/um/drivers/vde_kern.c b/arch/um/drivers/vde_kern.c index c5d01685d2b5..add7e722defb 100644 --- a/arch/um/drivers/vde_kern.c +++ b/arch/um/drivers/vde_kern.c @@ -36,30 +36,25 @@ static void vde_init(struct net_device *dev, void *data) printk("\n"); } -static int vde_read(int fd, struct sk_buff **skb, struct uml_net_private *lp) +static int vde_read(int fd, struct sk_buff *skb, struct uml_net_private *lp) { struct vde_data *pri = (struct vde_data *) &lp->user; - if (pri->conn != NULL) { - *skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER); - if (*skb == NULL) - return -ENOMEM; - - return vde_user_read(pri->conn, skb_mac_header(*skb), - (*skb)->dev->mtu + ETH_HEADER_OTHER); - } + if (pri->conn != NULL) + return vde_user_read(pri->conn, skb_mac_header(skb), + skb->dev->mtu + ETH_HEADER_OTHER); printk(KERN_ERR "vde_read - we have no VDECONN to read from"); return -EBADF; } -static int vde_write(int fd, struct sk_buff **skb, struct uml_net_private *lp) +static int vde_write(int fd, struct sk_buff *skb, struct uml_net_private *lp) { struct vde_data *pri = (struct vde_data *) &lp->user; if (pri->conn != NULL) - return vde_user_write((void *)pri->conn, (*skb)->data, - (*skb)->len); + return vde_user_write((void *)pri->conn, skb->data, + skb->len); printk(KERN_ERR "vde_write - we have no VDECONN to write to"); return -EBADF; diff --git a/arch/um/drivers/vde_user.c b/arch/um/drivers/vde_user.c index 7533cd3cbba4..d9941fe5f931 100644 --- a/arch/um/drivers/vde_user.c +++ b/arch/um/drivers/vde_user.c @@ -12,8 +12,6 @@ #include "user.h" #include "vde.h" -#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER) - static int vde_user_init(void *data, void *dev) { struct vde_data *pri = data; @@ -65,20 +63,15 @@ static void vde_remove(void *data) printk(UM_KERN_WARNING "vde_remove - we have no VDECONN to remove"); } -static int vde_set_mtu(int mtu, void *data) -{ - return mtu; -} - const struct net_user_info vde_user_info = { .init = vde_user_init, .open = vde_user_open, .close = NULL, .remove = vde_remove, - .set_mtu = vde_set_mtu, .add_address = NULL, .delete_address = NULL, - .max_packet = MAX_PACKET - ETH_HEADER_OTHER + .mtu = ETH_MAX_PACKET, + .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER, }; void vde_init_libstuff(struct vde_data *vpri, struct vde_init *init) -- cgit v1.2.2