diff options
Diffstat (limited to 'compat/backport-3.18.c')
| -rw-r--r-- | compat/backport-3.18.c | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/compat/backport-3.18.c b/compat/backport-3.18.c new file mode 100644 index 0000000..9a4e36e --- /dev/null +++ b/compat/backport-3.18.c @@ -0,0 +1,334 @@ +/* + * Copyright (c) 2014 Hauke Mehrtens <hauke@hauke-m.de> + * + * Backport functionality introduced in Linux 3.18. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/if_ether.h> +#include <linux/if_vlan.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <scsi/fc/fc_fcoe.h> +#include <linux/skbuff.h> +#include <linux/errqueue.h> +#include <linux/wait.h> +#include <linux/of.h> +#include <linux/string.h> + +/** + * eth_get_headlen - determine the the length of header for an ethernet frame + * @data: pointer to start of frame + * @len: total length of frame + * + * Make a best effort attempt to pull the length for all of the headers for + * a given frame in a linear buffer. + */ +int eth_get_headlen(unsigned char *data, unsigned int max_len) +{ + union { + unsigned char *network; + /* l2 headers */ + struct ethhdr *eth; + struct vlan_hdr *vlan; + /* l3 headers */ + struct iphdr *ipv4; + struct ipv6hdr *ipv6; + } hdr; + __be16 protocol; + u8 nexthdr = 0; /* default to not TCP */ + u8 hlen; + + /* this should never happen, but better safe than sorry */ + if (max_len < ETH_HLEN) + return max_len; + + /* initialize network frame pointer */ + hdr.network = data; + + /* set first protocol and move network header forward */ + protocol = hdr.eth->h_proto; + hdr.network += ETH_HLEN; + + /* handle any vlan tag if present */ + if (protocol == htons(ETH_P_8021Q)) { + if ((hdr.network - data) > (max_len - VLAN_HLEN)) + return max_len; + + protocol = hdr.vlan->h_vlan_encapsulated_proto; + hdr.network += VLAN_HLEN; + } + + /* handle L3 protocols */ + if (protocol == htons(ETH_P_IP)) { + if ((hdr.network - data) > (max_len - sizeof(struct iphdr))) + return max_len; + + /* access ihl as a u8 to avoid unaligned access on ia64 */ + hlen = (hdr.network[0] & 0x0F) << 2; + + /* verify hlen meets minimum size requirements */ + if (hlen < sizeof(struct iphdr)) + return hdr.network - data; + + /* record next protocol if header is present */ + if (!(hdr.ipv4->frag_off & htons(IP_OFFSET))) + nexthdr = hdr.ipv4->protocol; + } else if (protocol == htons(ETH_P_IPV6)) { + if ((hdr.network - data) > (max_len - sizeof(struct ipv6hdr))) + return max_len; + + /* record next protocol */ + nexthdr = hdr.ipv6->nexthdr; + hlen = sizeof(struct ipv6hdr); + } else if (protocol == htons(ETH_P_FCOE)) { + if ((hdr.network - data) > (max_len - FCOE_HEADER_LEN)) + return max_len; + hlen = FCOE_HEADER_LEN; + } else { + return hdr.network - data; + } + + /* relocate pointer to start of L4 header */ + hdr.network += hlen; + + /* finally sort out TCP/UDP */ + if (nexthdr == IPPROTO_TCP) { + if ((hdr.network - data) > (max_len - sizeof(struct tcphdr))) + return max_len; + + /* access doff as a u8 to avoid unaligned access on ia64 */ + hlen = (hdr.network[12] & 0xF0) >> 2; + + /* verify hlen meets minimum size requirements */ + if (hlen < sizeof(struct tcphdr)) + return hdr.network - data; + + hdr.network += hlen; + } else if (nexthdr == IPPROTO_UDP) { + if ((hdr.network - data) > (max_len - sizeof(struct udphdr))) + return max_len; + + hdr.network += sizeof(struct udphdr); + } + + /* + * If everything has gone correctly hdr.network should be the + * data section of the packet and will be the end of the header. + * If not then it probably represents the end of the last recognized + * header. + */ + if ((hdr.network - data) < max_len) + return hdr.network - data; + else + return max_len; +} +EXPORT_SYMBOL_GPL(eth_get_headlen); + +#define sock_efree LINUX_BACKPORT(sock_efree) +static void sock_efree(struct sk_buff *skb) +{ + sock_put(skb->sk); +} + +/** + * skb_clone_sk - create clone of skb, and take reference to socket + * @skb: the skb to clone + * + * This function creates a clone of a buffer that holds a reference on + * sk_refcnt. Buffers created via this function are meant to be + * returned using sock_queue_err_skb, or free via kfree_skb. + * + * When passing buffers allocated with this function to sock_queue_err_skb + * it is necessary to wrap the call with sock_hold/sock_put in order to + * prevent the socket from being released prior to being enqueued on + * the sk_error_queue. + */ +struct sk_buff *skb_clone_sk(struct sk_buff *skb) +{ + struct sock *sk = skb->sk; + struct sk_buff *clone; + + if (!sk || !atomic_inc_not_zero(&sk->sk_refcnt)) + return NULL; + + clone = skb_clone(skb, GFP_ATOMIC); + if (!clone) { + sock_put(sk); + return NULL; + } + + clone->sk = sk; + clone->destructor = sock_efree; + + return clone; +} +EXPORT_SYMBOL_GPL(skb_clone_sk); + +#if LINUX_VERSION_IS_GEQ(3,3,0) +/* + * skb_complete_wifi_ack() needs to get backported, because the version from + * 3.18 added the sock_hold() and sock_put() calles missing in older versions. + */ +void skb_complete_wifi_ack(struct sk_buff *skb, bool acked) +{ + struct sock *sk = skb->sk; + struct sock_exterr_skb *serr; + int err; + +#if LINUX_VERSION_IS_GEQ(3,3,0) + skb->wifi_acked_valid = 1; + skb->wifi_acked = acked; +#endif + + serr = SKB_EXT_ERR(skb); + memset(serr, 0, sizeof(*serr)); + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS; + + /* take a reference to prevent skb_orphan() from freeing the socket */ + sock_hold(sk); + + err = sock_queue_err_skb(sk, skb); + if (err) + kfree_skb(skb); + + sock_put(sk); +} +EXPORT_SYMBOL_GPL(skb_complete_wifi_ack); +#endif + +#if LINUX_VERSION_IS_GEQ(3,17,0) +int __sched out_of_line_wait_on_bit_timeout( + void *word, int bit, wait_bit_action_f *action, + unsigned mode, unsigned long timeout) +{ + wait_queue_head_t *wq = bit_waitqueue(word, bit); + DEFINE_WAIT_BIT(wait, word, bit); + + wait.key.private = jiffies + timeout; + return __wait_on_bit(wq, &wait, action, mode); +} +EXPORT_SYMBOL_GPL(out_of_line_wait_on_bit_timeout); + +__sched int bit_wait_timeout(struct wait_bit_key *word) +{ + unsigned long now = ACCESS_ONCE(jiffies); + if (signal_pending_state(current->state, current)) + return 1; + if (time_after_eq(now, word->private)) + return -EAGAIN; + schedule_timeout(word->private - now); + return 0; +} +EXPORT_SYMBOL_GPL(bit_wait_timeout); +#endif + +#ifdef CONFIG_OF +/** + * of_find_property_value_of_size + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @len: requested length of property value + * + * Search for a property in a device node and valid the requested size. + * Returns the property value on success, -EINVAL if the property does not + * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + * + */ +void *of_find_property_value_of_size(const struct device_node *np, + const char *propname, u32 len) +{ + struct property *prop = of_find_property(np, propname, NULL); + + if (!prop) + return ERR_PTR(-EINVAL); + if (!prop->value) + return ERR_PTR(-ENODATA); + if (len > prop->length) + return ERR_PTR(-EOVERFLOW); + + return prop->value; +} + +/** + * of_property_read_u64_array - Find and read an array of 64 bit integers + * from a property. + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_values: pointer to return value, modified only if return value is 0. + * @sz: number of array elements to read + * + * Search for a property in a device node and read 64-bit value(s) from + * it. Returns 0 on success, -EINVAL if the property does not exist, + * -ENODATA if property does not have a value, and -EOVERFLOW if the + * property data isn't large enough. + * + * The out_values is modified only if a valid u64 value can be decoded. + */ +int of_property_read_u64_array(const struct device_node *np, + const char *propname, u64 *out_values, + size_t sz) +{ + const __be32 *val = of_find_property_value_of_size(np, propname, + (sz * sizeof(*out_values))); + + if (IS_ERR(val)) + return PTR_ERR(val); + + while (sz--) { + *out_values++ = of_read_number(val, 2); + val += 2; + } + return 0; +} +EXPORT_SYMBOL_GPL(of_property_read_u64_array); +#endif /* CONFIG_OF */ + +#if !(LINUX_VERSION_IS_GEQ(3,17,3) || \ + (LINUX_VERSION_IS_GEQ(3,14,24) && \ + LINUX_VERSION_IS_LESS(3,15,0)) || \ + (LINUX_VERSION_IS_GEQ(3,12,33) && \ + LINUX_VERSION_IS_LESS(3,13,0)) || \ + (LINUX_VERSION_IS_GEQ(3,10,60) && \ + LINUX_VERSION_IS_LESS(3,11,0)) || \ + (LINUX_VERSION_IS_GEQ(3,4,106) && \ + LINUX_VERSION_IS_LESS(3,5,0)) || \ + (LINUX_VERSION_IS_GEQ(3,2,65) && \ + LINUX_VERSION_IS_LESS(3,3,0))) +/** + * memzero_explicit - Fill a region of memory (e.g. sensitive + * keying data) with 0s. + * @s: Pointer to the start of the area. + * @count: The size of the area. + * + * Note: usually using memset() is just fine (!), but in cases + * where clearing out _local_ data at the end of a scope is + * necessary, memzero_explicit() should be used instead in + * order to prevent the compiler from optimising away zeroing. + * + * memzero_explicit() doesn't need an arch-specific version as + * it just invokes the one of memset() implicitly. + */ +void memzero_explicit(void *s, size_t count) +{ + memset(s, 0, count); + barrier_data(s); +} +EXPORT_SYMBOL_GPL(memzero_explicit); +#endif + +char *bin2hex(char *dst, const void *src, size_t count) +{ + const unsigned char *_src = src; + + while (count--) + dst = hex_byte_pack(dst, *_src++); + return dst; +} +EXPORT_SYMBOL(bin2hex); |