diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/defs.h | 49 | ||||
| -rw-r--r-- | kernel/e1000.c | 129 | ||||
| -rw-r--r-- | kernel/e1000_dev.h | 125 | ||||
| -rw-r--r-- | kernel/file.c | 21 | ||||
| -rw-r--r-- | kernel/file.h | 8 | ||||
| -rw-r--r-- | kernel/main.c | 12 | ||||
| -rw-r--r-- | kernel/net.c | 374 | ||||
| -rw-r--r-- | kernel/net.h | 173 | ||||
| -rw-r--r-- | kernel/pci.c | 61 | ||||
| -rw-r--r-- | kernel/plic.c | 12 | ||||
| -rw-r--r-- | kernel/spinlock.c | 111 | ||||
| -rw-r--r-- | kernel/syscall.c | 8 | ||||
| -rw-r--r-- | kernel/sysfile.c | 26 | ||||
| -rw-r--r-- | kernel/sysnet.c | 185 | ||||
| -rw-r--r-- | kernel/trap.c | 11 | ||||
| -rw-r--r-- | kernel/vm.c | 31 | 
16 files changed, 1316 insertions, 20 deletions
| diff --git a/kernel/defs.h b/kernel/defs.h index 870c984..02226b5 100644 --- a/kernel/defs.h +++ b/kernel/defs.h @@ -8,6 +8,10 @@ struct spinlock;  struct sleeplock;  struct stat;  struct superblock; +#ifdef LAB_NET +struct mbuf; +struct sock; +#endif  struct sysinfo;  // bio.c @@ -127,6 +131,10 @@ void            initlock(struct spinlock*, char*);  void            release(struct spinlock*);  void            push_off(void);  void            pop_off(void); +int             atomic_read4(int *addr); +#ifdef LAB_LOCK +void            freelock(struct spinlock*); +#endif  // sleeplock.c  void            acquiresleep(struct sleeplock*); @@ -201,3 +209,44 @@ void            virtio_disk_intr(void);  // number of elements in fixed-size array  #define NELEM(x) (sizeof(x)/sizeof((x)[0])) + + + +#ifdef LAB_PGTBL +// vmcopyin.c +int             copyin_new(pagetable_t, char *, uint64, uint64); +int             copyinstr_new(pagetable_t, char *, uint64, uint64); +#endif + +// stats.c +void            statsinit(void); +void            statsinc(void); + +// sprintf.c +int             snprintf(char*, int, char*, ...); + +#ifdef KCSAN +void            kcsaninit(); +#endif + +#ifdef LAB_NET +// pci.c +void            pci_init(); + +// e1000.c +void            e1000_init(uint32 *); +void            e1000_intr(void); +int             e1000_transmit(struct mbuf*); + +// net.c +void            net_rx(struct mbuf*); +void            net_tx_udp(struct mbuf*, uint32, uint16, uint16); + +// sysnet.c +void            sockinit(void); +int             sockalloc(struct file **, uint32, uint16, uint16); +void            sockclose(struct sock *); +int             sockread(struct sock *, uint64, int); +int             sockwrite(struct sock *, uint64, int); +void            sockrecvudp(struct mbuf*, uint32, uint16, uint16); +#endif diff --git a/kernel/e1000.c b/kernel/e1000.c new file mode 100644 index 0000000..70a2adf --- /dev/null +++ b/kernel/e1000.c @@ -0,0 +1,129 @@ +#include "types.h" +#include "param.h" +#include "memlayout.h" +#include "riscv.h" +#include "spinlock.h" +#include "proc.h" +#include "defs.h" +#include "e1000_dev.h" +#include "net.h" + +#define TX_RING_SIZE 16 +static struct tx_desc tx_ring[TX_RING_SIZE] __attribute__((aligned(16))); +static struct mbuf *tx_mbufs[TX_RING_SIZE]; + +#define RX_RING_SIZE 16 +static struct rx_desc rx_ring[RX_RING_SIZE] __attribute__((aligned(16))); +static struct mbuf *rx_mbufs[RX_RING_SIZE]; + +// remember where the e1000's registers live. +static volatile uint32 *regs; + +struct spinlock e1000_lock; + +// called by pci_init(). +// xregs is the memory address at which the +// e1000's registers are mapped. +void +e1000_init(uint32 *xregs) +{ +  int i; + +  initlock(&e1000_lock, "e1000"); + +  regs = xregs; + +  // Reset the device +  regs[E1000_IMS] = 0; // disable interrupts +  regs[E1000_CTL] |= E1000_CTL_RST; +  regs[E1000_IMS] = 0; // redisable interrupts +  __sync_synchronize(); + +  // [E1000 14.5] Transmit initialization +  memset(tx_ring, 0, sizeof(tx_ring)); +  for (i = 0; i < TX_RING_SIZE; i++) { +    tx_ring[i].status = E1000_TXD_STAT_DD; +    tx_mbufs[i] = 0; +  } +  regs[E1000_TDBAL] = (uint64) tx_ring; +  if(sizeof(tx_ring) % 128 != 0) +    panic("e1000"); +  regs[E1000_TDLEN] = sizeof(tx_ring); +  regs[E1000_TDH] = regs[E1000_TDT] = 0; +   +  // [E1000 14.4] Receive initialization +  memset(rx_ring, 0, sizeof(rx_ring)); +  for (i = 0; i < RX_RING_SIZE; i++) { +    rx_mbufs[i] = mbufalloc(0); +    if (!rx_mbufs[i]) +      panic("e1000"); +    rx_ring[i].addr = (uint64) rx_mbufs[i]->head; +  } +  regs[E1000_RDBAL] = (uint64) rx_ring; +  if(sizeof(rx_ring) % 128 != 0) +    panic("e1000"); +  regs[E1000_RDH] = 0; +  regs[E1000_RDT] = RX_RING_SIZE - 1; +  regs[E1000_RDLEN] = sizeof(rx_ring); + +  // filter by qemu's MAC address, 52:54:00:12:34:56 +  regs[E1000_RA] = 0x12005452; +  regs[E1000_RA+1] = 0x5634 | (1<<31); +  // multicast table +  for (int i = 0; i < 4096/32; i++) +    regs[E1000_MTA + i] = 0; + +  // transmitter control bits. +  regs[E1000_TCTL] = E1000_TCTL_EN |  // enable +    E1000_TCTL_PSP |                  // pad short packets +    (0x10 << E1000_TCTL_CT_SHIFT) |   // collision stuff +    (0x40 << E1000_TCTL_COLD_SHIFT); +  regs[E1000_TIPG] = 10 | (8<<10) | (6<<20); // inter-pkt gap + +  // receiver control bits. +  regs[E1000_RCTL] = E1000_RCTL_EN | // enable receiver +    E1000_RCTL_BAM |                 // enable broadcast +    E1000_RCTL_SZ_2048 |             // 2048-byte rx buffers +    E1000_RCTL_SECRC;                // strip CRC +   +  // ask e1000 for receive interrupts. +  regs[E1000_RDTR] = 0; // interrupt after every received packet (no timer) +  regs[E1000_RADV] = 0; // interrupt after every packet (no timer) +  regs[E1000_IMS] = (1 << 7); // RXDW -- Receiver Descriptor Write Back +} + +int +e1000_transmit(struct mbuf *m) +{ +  // +  // Your code here. +  // +  // the mbuf contains an ethernet frame; program it into +  // the TX descriptor ring so that the e1000 sends it. Stash +  // a pointer so that it can be freed after sending. +  // +   +  return 0; +} + +static void +e1000_recv(void) +{ +  // +  // Your code here. +  // +  // Check for packets that have arrived from the e1000 +  // Create and deliver an mbuf for each packet (using net_rx()). +  // +} + +void +e1000_intr(void) +{ +  // tell the e1000 we've seen this interrupt; +  // without this the e1000 won't raise any +  // further interrupts. +  regs[E1000_ICR] = 0xffffffff; + +  e1000_recv(); +} diff --git a/kernel/e1000_dev.h b/kernel/e1000_dev.h new file mode 100644 index 0000000..9b462df --- /dev/null +++ b/kernel/e1000_dev.h @@ -0,0 +1,125 @@ +// +// E1000 hardware definitions: registers and DMA ring format. +// from the Intel 82540EP/EM &c manual. +// + +/* Registers */ +#define E1000_CTL      (0x00000/4)  /* Device Control Register - RW */ +#define E1000_ICR      (0x000C0/4)  /* Interrupt Cause Read - R */ +#define E1000_IMS      (0x000D0/4)  /* Interrupt Mask Set - RW */ +#define E1000_RCTL     (0x00100/4)  /* RX Control - RW */ +#define E1000_TCTL     (0x00400/4)  /* TX Control - RW */ +#define E1000_TIPG     (0x00410/4)  /* TX Inter-packet gap -RW */ +#define E1000_RDBAL    (0x02800/4)  /* RX Descriptor Base Address Low - RW */ +#define E1000_RDTR     (0x02820/4)  /* RX Delay Timer */ +#define E1000_RADV     (0x0282C/4)  /* RX Interrupt Absolute Delay Timer */ +#define E1000_RDH      (0x02810/4)  /* RX Descriptor Head - RW */ +#define E1000_RDT      (0x02818/4)  /* RX Descriptor Tail - RW */ +#define E1000_RDLEN    (0x02808/4)  /* RX Descriptor Length - RW */ +#define E1000_RSRPD    (0x02C00/4)  /* RX Small Packet Detect Interrupt */ +#define E1000_TDBAL    (0x03800/4)  /* TX Descriptor Base Address Low - RW */ +#define E1000_TDLEN    (0x03808/4)  /* TX Descriptor Length - RW */ +#define E1000_TDH      (0x03810/4)  /* TX Descriptor Head - RW */ +#define E1000_TDT      (0x03818/4)  /* TX Descripotr Tail - RW */ +#define E1000_MTA      (0x05200/4)  /* Multicast Table Array - RW Array */ +#define E1000_RA       (0x05400/4)  /* Receive Address - RW Array */ + +/* Device Control */ +#define E1000_CTL_SLU     0x00000040    /* set link up */ +#define E1000_CTL_FRCSPD  0x00000800    /* force speed */ +#define E1000_CTL_FRCDPLX 0x00001000    /* force duplex */ +#define E1000_CTL_RST     0x00400000    /* full reset */ + +/* Transmit Control */ +#define E1000_TCTL_RST    0x00000001    /* software reset */ +#define E1000_TCTL_EN     0x00000002    /* enable tx */ +#define E1000_TCTL_BCE    0x00000004    /* busy check enable */ +#define E1000_TCTL_PSP    0x00000008    /* pad short packets */ +#define E1000_TCTL_CT     0x00000ff0    /* collision threshold */ +#define E1000_TCTL_CT_SHIFT 4 +#define E1000_TCTL_COLD   0x003ff000    /* collision distance */ +#define E1000_TCTL_COLD_SHIFT 12 +#define E1000_TCTL_SWXOFF 0x00400000    /* SW Xoff transmission */ +#define E1000_TCTL_PBE    0x00800000    /* Packet Burst Enable */ +#define E1000_TCTL_RTLC   0x01000000    /* Re-transmit on late collision */ +#define E1000_TCTL_NRTU   0x02000000    /* No Re-transmit on underrun */ +#define E1000_TCTL_MULR   0x10000000    /* Multiple request support */ + +/* Receive Control */ +#define E1000_RCTL_RST            0x00000001    /* Software reset */ +#define E1000_RCTL_EN             0x00000002    /* enable */ +#define E1000_RCTL_SBP            0x00000004    /* store bad packet */ +#define E1000_RCTL_UPE            0x00000008    /* unicast promiscuous enable */ +#define E1000_RCTL_MPE            0x00000010    /* multicast promiscuous enab */ +#define E1000_RCTL_LPE            0x00000020    /* long packet enable */ +#define E1000_RCTL_LBM_NO         0x00000000    /* no loopback mode */ +#define E1000_RCTL_LBM_MAC        0x00000040    /* MAC loopback mode */ +#define E1000_RCTL_LBM_SLP        0x00000080    /* serial link loopback mode */ +#define E1000_RCTL_LBM_TCVR       0x000000C0    /* tcvr loopback mode */ +#define E1000_RCTL_DTYP_MASK      0x00000C00    /* Descriptor type mask */ +#define E1000_RCTL_DTYP_PS        0x00000400    /* Packet Split descriptor */ +#define E1000_RCTL_RDMTS_HALF     0x00000000    /* rx desc min threshold size */ +#define E1000_RCTL_RDMTS_QUAT     0x00000100    /* rx desc min threshold size */ +#define E1000_RCTL_RDMTS_EIGTH    0x00000200    /* rx desc min threshold size */ +#define E1000_RCTL_MO_SHIFT       12            /* multicast offset shift */ +#define E1000_RCTL_MO_0           0x00000000    /* multicast offset 11:0 */ +#define E1000_RCTL_MO_1           0x00001000    /* multicast offset 12:1 */ +#define E1000_RCTL_MO_2           0x00002000    /* multicast offset 13:2 */ +#define E1000_RCTL_MO_3           0x00003000    /* multicast offset 15:4 */ +#define E1000_RCTL_MDR            0x00004000    /* multicast desc ring 0 */ +#define E1000_RCTL_BAM            0x00008000    /* broadcast enable */ +/* these buffer sizes are valid if E1000_RCTL_BSEX is 0 */ +#define E1000_RCTL_SZ_2048        0x00000000    /* rx buffer size 2048 */ +#define E1000_RCTL_SZ_1024        0x00010000    /* rx buffer size 1024 */ +#define E1000_RCTL_SZ_512         0x00020000    /* rx buffer size 512 */ +#define E1000_RCTL_SZ_256         0x00030000    /* rx buffer size 256 */ +/* these buffer sizes are valid if E1000_RCTL_BSEX is 1 */ +#define E1000_RCTL_SZ_16384       0x00010000    /* rx buffer size 16384 */ +#define E1000_RCTL_SZ_8192        0x00020000    /* rx buffer size 8192 */ +#define E1000_RCTL_SZ_4096        0x00030000    /* rx buffer size 4096 */ +#define E1000_RCTL_VFE            0x00040000    /* vlan filter enable */ +#define E1000_RCTL_CFIEN          0x00080000    /* canonical form enable */ +#define E1000_RCTL_CFI            0x00100000    /* canonical form indicator */ +#define E1000_RCTL_DPF            0x00400000    /* discard pause frames */ +#define E1000_RCTL_PMCF           0x00800000    /* pass MAC control frames */ +#define E1000_RCTL_BSEX           0x02000000    /* Buffer size extension */ +#define E1000_RCTL_SECRC          0x04000000    /* Strip Ethernet CRC */ +#define E1000_RCTL_FLXBUF_MASK    0x78000000    /* Flexible buffer size */ +#define E1000_RCTL_FLXBUF_SHIFT   27            /* Flexible buffer shift */ + +#define DATA_MAX 1518 + +/* Transmit Descriptor command definitions [E1000 3.3.3.1] */ +#define E1000_TXD_CMD_EOP    0x01 /* End of Packet */ +#define E1000_TXD_CMD_RS     0x08 /* Report Status */ + +/* Transmit Descriptor status definitions [E1000 3.3.3.2] */ +#define E1000_TXD_STAT_DD    0x00000001 /* Descriptor Done */ + +// [E1000 3.3.3] +struct tx_desc +{ +  uint64 addr; +  uint16 length; +  uint8 cso; +  uint8 cmd; +  uint8 status; +  uint8 css; +  uint16 special; +}; + +/* Receive Descriptor bit definitions [E1000 3.2.3.1] */ +#define E1000_RXD_STAT_DD       0x01    /* Descriptor Done */ +#define E1000_RXD_STAT_EOP      0x02    /* End of Packet */ + +// [E1000 3.2.3] +struct rx_desc +{ +  uint64 addr;       /* Address of the descriptor's data buffer */ +  uint16 length;     /* Length of data DMAed into data buffer */ +  uint16 csum;       /* Packet checksum */ +  uint8 status;      /* Descriptor status */ +  uint8 errors;      /* Descriptor Errors */ +  uint16 special; +}; + diff --git a/kernel/file.c b/kernel/file.c index 25fa226..0fba21b 100644 --- a/kernel/file.c +++ b/kernel/file.c @@ -80,6 +80,11 @@ fileclose(struct file *f)      iput(ff.ip);      end_op();    } +#ifdef LAB_NET +  else if(ff.type == FD_SOCK){ +    sockclose(ff.sock); +  } +#endif  }  // Get metadata about file f. @@ -122,7 +127,13 @@ fileread(struct file *f, uint64 addr, int n)      if((r = readi(f->ip, 1, addr, f->off, n)) > 0)        f->off += r;      iunlock(f->ip); -  } else { +  } +#ifdef LAB_NET +  else if(f->type == FD_SOCK){ +    r = sockread(f->sock, addr, n); +  } +#endif +  else {      panic("fileread");    } @@ -173,7 +184,13 @@ filewrite(struct file *f, uint64 addr, int n)        i += r;      }      ret = (i == n ? n : -1); -  } else { +  } +#ifdef LAB_NET +  else if(f->type == FD_SOCK){ +    ret = sockwrite(f->sock, addr, n); +  } +#endif +  else {      panic("filewrite");    } diff --git a/kernel/file.h b/kernel/file.h index b076d1d..1eb5107 100644 --- a/kernel/file.h +++ b/kernel/file.h @@ -1,10 +1,17 @@  struct file { +#ifdef LAB_NET +  enum { FD_NONE, FD_PIPE, FD_INODE, FD_DEVICE, FD_SOCK } type; +#else    enum { FD_NONE, FD_PIPE, FD_INODE, FD_DEVICE } type; +#endif    int ref; // reference count    char readable;    char writable;    struct pipe *pipe; // FD_PIPE    struct inode *ip;  // FD_INODE and FD_DEVICE +#ifdef LAB_NET +  struct sock *sock; // FD_SOCK +#endif    uint off;          // FD_INODE    short major;       // FD_DEVICE  }; @@ -38,3 +45,4 @@ struct devsw {  extern struct devsw devsw[];  #define CONSOLE 1 +#define STATS   2 diff --git a/kernel/main.c b/kernel/main.c index f0d3171..48c9555 100644 --- a/kernel/main.c +++ b/kernel/main.c @@ -12,6 +12,9 @@ main()  {    if(cpuid() == 0){      consoleinit(); +#if defined(LAB_LOCK) +    statsinit(); +#endif      printfinit();      printf("\n");      printf("xv6 kernel is booting\n"); @@ -28,11 +31,18 @@ main()      iinit();         // inode table      fileinit();      // file table      virtio_disk_init(); // emulated hard disk +#ifdef LAB_NET +    pci_init(); +    sockinit(); +#endif          userinit();      // first user process +#ifdef KCSAN +    kcsaninit(); +#endif      __sync_synchronize();      started = 1;    } else { -    while(started == 0) +    while(atomic_read4((int *) &started) == 0)        ;      __sync_synchronize();      printf("hart %d starting\n", cpuid()); diff --git a/kernel/net.c b/kernel/net.c new file mode 100644 index 0000000..137ea2b --- /dev/null +++ b/kernel/net.c @@ -0,0 +1,374 @@ +// +// networking protocol support (IP, UDP, ARP, etc.). +// + +#include "types.h" +#include "param.h" +#include "memlayout.h" +#include "riscv.h" +#include "spinlock.h" +#include "proc.h" +#include "net.h" +#include "defs.h" + +static uint32 local_ip = MAKE_IP_ADDR(10, 0, 2, 15); // qemu's idea of the guest IP +static uint8 local_mac[ETHADDR_LEN] = { 0x52, 0x54, 0x00, 0x12, 0x34, 0x56 }; +static uint8 broadcast_mac[ETHADDR_LEN] = { 0xFF, 0XFF, 0XFF, 0XFF, 0XFF, 0XFF }; + +// Strips data from the start of the buffer and returns a pointer to it. +// Returns 0 if less than the full requested length is available. +char * +mbufpull(struct mbuf *m, unsigned int len) +{ +  char *tmp = m->head; +  if (m->len < len) +    return 0; +  m->len -= len; +  m->head += len; +  return tmp; +} + +// Prepends data to the beginning of the buffer and returns a pointer to it. +char * +mbufpush(struct mbuf *m, unsigned int len) +{ +  m->head -= len; +  if (m->head < m->buf) +    panic("mbufpush"); +  m->len += len; +  return m->head; +} + +// Appends data to the end of the buffer and returns a pointer to it. +char * +mbufput(struct mbuf *m, unsigned int len) +{ +  char *tmp = m->head + m->len; +  m->len += len; +  if (m->len > MBUF_SIZE) +    panic("mbufput"); +  return tmp; +} + +// Strips data from the end of the buffer and returns a pointer to it. +// Returns 0 if less than the full requested length is available. +char * +mbuftrim(struct mbuf *m, unsigned int len) +{ +  if (len > m->len) +    return 0; +  m->len -= len; +  return m->head + m->len; +} + +// Allocates a packet buffer. +struct mbuf * +mbufalloc(unsigned int headroom) +{ +  struct mbuf *m; +  +  if (headroom > MBUF_SIZE) +    return 0; +  m = kalloc(); +  if (m == 0) +    return 0; +  m->next = 0; +  m->head = (char *)m->buf + headroom; +  m->len = 0; +  memset(m->buf, 0, sizeof(m->buf)); +  return m; +} + +// Frees a packet buffer. +void +mbuffree(struct mbuf *m) +{ +  kfree(m); +} + +// Pushes an mbuf to the end of the queue. +void +mbufq_pushtail(struct mbufq *q, struct mbuf *m) +{ +  m->next = 0; +  if (!q->head){ +    q->head = q->tail = m; +    return; +  } +  q->tail->next = m; +  q->tail = m; +} + +// Pops an mbuf from the start of the queue. +struct mbuf * +mbufq_pophead(struct mbufq *q) +{ +  struct mbuf *head = q->head; +  if (!head) +    return 0; +  q->head = head->next; +  return head; +} + +// Returns one (nonzero) if the queue is empty. +int +mbufq_empty(struct mbufq *q) +{ +  return q->head == 0; +} + +// Intializes a queue of mbufs. +void +mbufq_init(struct mbufq *q) +{ +  q->head = 0; +} + +// This code is lifted from FreeBSD's ping.c, and is copyright by the Regents +// of the University of California. +static unsigned short +in_cksum(const unsigned char *addr, int len) +{ +  int nleft = len; +  const unsigned short *w = (const unsigned short *)addr; +  unsigned int sum = 0; +  unsigned short answer = 0; + +  /* +   * Our algorithm is simple, using a 32 bit accumulator (sum), we add +   * sequential 16 bit words to it, and at the end, fold back all the +   * carry bits from the top 16 bits into the lower 16 bits. +   */ +  while (nleft > 1)  { +    sum += *w++; +    nleft -= 2; +  } + +  /* mop up an odd byte, if necessary */ +  if (nleft == 1) { +    *(unsigned char *)(&answer) = *(const unsigned char *)w; +    sum += answer; +  } + +  /* add back carry outs from top 16 bits to low 16 bits */ +  sum = (sum & 0xffff) + (sum >> 16); +  sum += (sum >> 16); +  /* guaranteed now that the lower 16 bits of sum are correct */ + +  answer = ~sum; /* truncate to 16 bits */ +  return answer; +} + +// sends an ethernet packet +static void +net_tx_eth(struct mbuf *m, uint16 ethtype) +{ +  struct eth *ethhdr; + +  ethhdr = mbufpushhdr(m, *ethhdr); +  memmove(ethhdr->shost, local_mac, ETHADDR_LEN); +  // In a real networking stack, dhost would be set to the address discovered +  // through ARP. Because we don't support enough of the ARP protocol, set it +  // to broadcast instead. +  memmove(ethhdr->dhost, broadcast_mac, ETHADDR_LEN); +  ethhdr->type = htons(ethtype); +  if (e1000_transmit(m)) { +    mbuffree(m); +  } +} + +// sends an IP packet +static void +net_tx_ip(struct mbuf *m, uint8 proto, uint32 dip) +{ +  struct ip *iphdr; + +  // push the IP header +  iphdr = mbufpushhdr(m, *iphdr); +  memset(iphdr, 0, sizeof(*iphdr)); +  iphdr->ip_vhl = (4 << 4) | (20 >> 2); +  iphdr->ip_p = proto; +  iphdr->ip_src = htonl(local_ip); +  iphdr->ip_dst = htonl(dip); +  iphdr->ip_len = htons(m->len); +  iphdr->ip_ttl = 100; +  iphdr->ip_sum = in_cksum((unsigned char *)iphdr, sizeof(*iphdr)); + +  // now on to the ethernet layer +  net_tx_eth(m, ETHTYPE_IP); +} + +// sends a UDP packet +void +net_tx_udp(struct mbuf *m, uint32 dip, +           uint16 sport, uint16 dport) +{ +  struct udp *udphdr; + +  // put the UDP header +  udphdr = mbufpushhdr(m, *udphdr); +  udphdr->sport = htons(sport); +  udphdr->dport = htons(dport); +  udphdr->ulen = htons(m->len); +  udphdr->sum = 0; // zero means no checksum is provided + +  // now on to the IP layer +  net_tx_ip(m, IPPROTO_UDP, dip); +} + +// sends an ARP packet +static int +net_tx_arp(uint16 op, uint8 dmac[ETHADDR_LEN], uint32 dip) +{ +  struct mbuf *m; +  struct arp *arphdr; + +  m = mbufalloc(MBUF_DEFAULT_HEADROOM); +  if (!m) +    return -1; + +  // generic part of ARP header +  arphdr = mbufputhdr(m, *arphdr); +  arphdr->hrd = htons(ARP_HRD_ETHER); +  arphdr->pro = htons(ETHTYPE_IP); +  arphdr->hln = ETHADDR_LEN; +  arphdr->pln = sizeof(uint32); +  arphdr->op = htons(op); + +  // ethernet + IP part of ARP header +  memmove(arphdr->sha, local_mac, ETHADDR_LEN); +  arphdr->sip = htonl(local_ip); +  memmove(arphdr->tha, dmac, ETHADDR_LEN); +  arphdr->tip = htonl(dip); + +  // header is ready, send the packet +  net_tx_eth(m, ETHTYPE_ARP); +  return 0; +} + +// receives an ARP packet +static void +net_rx_arp(struct mbuf *m) +{ +  struct arp *arphdr; +  uint8 smac[ETHADDR_LEN]; +  uint32 sip, tip; + +  arphdr = mbufpullhdr(m, *arphdr); +  if (!arphdr) +    goto done; + +  // validate the ARP header +  if (ntohs(arphdr->hrd) != ARP_HRD_ETHER || +      ntohs(arphdr->pro) != ETHTYPE_IP || +      arphdr->hln != ETHADDR_LEN || +      arphdr->pln != sizeof(uint32)) { +    goto done; +  } + +  // only requests are supported so far +  // check if our IP was solicited +  tip = ntohl(arphdr->tip); // target IP address +  if (ntohs(arphdr->op) != ARP_OP_REQUEST || tip != local_ip) +    goto done; + +  // handle the ARP request +  memmove(smac, arphdr->sha, ETHADDR_LEN); // sender's ethernet address +  sip = ntohl(arphdr->sip); // sender's IP address (qemu's slirp) +  net_tx_arp(ARP_OP_REPLY, smac, sip); + +done: +  mbuffree(m); +} + +// receives a UDP packet +static void +net_rx_udp(struct mbuf *m, uint16 len, struct ip *iphdr) +{ +  struct udp *udphdr; +  uint32 sip; +  uint16 sport, dport; + + +  udphdr = mbufpullhdr(m, *udphdr); +  if (!udphdr) +    goto fail; + +  // TODO: validate UDP checksum + +  // validate lengths reported in headers +  if (ntohs(udphdr->ulen) != len) +    goto fail; +  len -= sizeof(*udphdr); +  if (len > m->len) +    goto fail; +  // minimum packet size could be larger than the payload +  mbuftrim(m, m->len - len); + +  // parse the necessary fields +  sip = ntohl(iphdr->ip_src); +  sport = ntohs(udphdr->sport); +  dport = ntohs(udphdr->dport); +  sockrecvudp(m, sip, dport, sport); +  return; + +fail: +  mbuffree(m); +} + +// receives an IP packet +static void +net_rx_ip(struct mbuf *m) +{ +  struct ip *iphdr; +  uint16 len; + +  iphdr = mbufpullhdr(m, *iphdr); +  if (!iphdr) +	  goto fail; + +  // check IP version and header len +  if (iphdr->ip_vhl != ((4 << 4) | (20 >> 2))) +    goto fail; +  // validate IP checksum +  if (in_cksum((unsigned char *)iphdr, sizeof(*iphdr))) +    goto fail; +  // can't support fragmented IP packets +  if (htons(iphdr->ip_off) != 0) +    goto fail; +  // is the packet addressed to us? +  if (htonl(iphdr->ip_dst) != local_ip) +    goto fail; +  // can only support UDP +  if (iphdr->ip_p != IPPROTO_UDP) +    goto fail; + +  len = ntohs(iphdr->ip_len) - sizeof(*iphdr); +  net_rx_udp(m, len, iphdr); +  return; + +fail: +  mbuffree(m); +} + +// called by e1000 driver's interrupt handler to deliver a packet to the +// networking stack +void net_rx(struct mbuf *m) +{ +  struct eth *ethhdr; +  uint16 type; + +  ethhdr = mbufpullhdr(m, *ethhdr); +  if (!ethhdr) { +    mbuffree(m); +    return; +  } + +  type = ntohs(ethhdr->type); +  if (type == ETHTYPE_IP) +    net_rx_ip(m); +  else if (type == ETHTYPE_ARP) +    net_rx_arp(m); +  else +    mbuffree(m); +} diff --git a/kernel/net.h b/kernel/net.h new file mode 100644 index 0000000..9e6fefe --- /dev/null +++ b/kernel/net.h @@ -0,0 +1,173 @@ +// +// packet buffer management +// + +#define MBUF_SIZE              2048 +#define MBUF_DEFAULT_HEADROOM  128 + +struct mbuf { +  struct mbuf  *next; // the next mbuf in the chain +  char         *head; // the current start position of the buffer +  unsigned int len;   // the length of the buffer +  char         buf[MBUF_SIZE]; // the backing store +}; + +char *mbufpull(struct mbuf *m, unsigned int len); +char *mbufpush(struct mbuf *m, unsigned int len); +char *mbufput(struct mbuf *m, unsigned int len); +char *mbuftrim(struct mbuf *m, unsigned int len); + +// The above functions manipulate the size and position of the buffer: +//            <- push            <- trim +//             -> pull            -> put +// [-headroom-][------buffer------][-tailroom-] +// |----------------MBUF_SIZE-----------------| +// +// These marcos automatically typecast and determine the size of header structs. +// In most situations you should use these instead of the raw ops above. +#define mbufpullhdr(mbuf, hdr) (typeof(hdr)*)mbufpull(mbuf, sizeof(hdr)) +#define mbufpushhdr(mbuf, hdr) (typeof(hdr)*)mbufpush(mbuf, sizeof(hdr)) +#define mbufputhdr(mbuf, hdr) (typeof(hdr)*)mbufput(mbuf, sizeof(hdr)) +#define mbuftrimhdr(mbuf, hdr) (typeof(hdr)*)mbuftrim(mbuf, sizeof(hdr)) + +struct mbuf *mbufalloc(unsigned int headroom); +void mbuffree(struct mbuf *m); + +struct mbufq { +  struct mbuf *head;  // the first element in the queue +  struct mbuf *tail;  // the last element in the queue +}; + +void mbufq_pushtail(struct mbufq *q, struct mbuf *m); +struct mbuf *mbufq_pophead(struct mbufq *q); +int mbufq_empty(struct mbufq *q); +void mbufq_init(struct mbufq *q); + + +// +// endianness support +// + +static inline uint16 bswaps(uint16 val) +{ +  return (((val & 0x00ffU) << 8) | +          ((val & 0xff00U) >> 8)); +} + +static inline uint32 bswapl(uint32 val) +{ +  return (((val & 0x000000ffUL) << 24) | +          ((val & 0x0000ff00UL) << 8) | +          ((val & 0x00ff0000UL) >> 8) | +          ((val & 0xff000000UL) >> 24)); +} + +// Use these macros to convert network bytes to the native byte order. +// Note that Risc-V uses little endian while network order is big endian. +#define ntohs bswaps +#define ntohl bswapl +#define htons bswaps +#define htonl bswapl + + +// +// useful networking headers +// + +#define ETHADDR_LEN 6 + +// an Ethernet packet header (start of the packet). +struct eth { +  uint8  dhost[ETHADDR_LEN]; +  uint8  shost[ETHADDR_LEN]; +  uint16 type; +} __attribute__((packed)); + +#define ETHTYPE_IP  0x0800 // Internet protocol +#define ETHTYPE_ARP 0x0806 // Address resolution protocol + +// an IP packet header (comes after an Ethernet header). +struct ip { +  uint8  ip_vhl; // version << 4 | header length >> 2 +  uint8  ip_tos; // type of service +  uint16 ip_len; // total length +  uint16 ip_id;  // identification +  uint16 ip_off; // fragment offset field +  uint8  ip_ttl; // time to live +  uint8  ip_p;   // protocol +  uint16 ip_sum; // checksum +  uint32 ip_src, ip_dst; +}; + +#define IPPROTO_ICMP 1  // Control message protocol +#define IPPROTO_TCP  6  // Transmission control protocol +#define IPPROTO_UDP  17 // User datagram protocol + +#define MAKE_IP_ADDR(a, b, c, d)           \ +  (((uint32)a << 24) | ((uint32)b << 16) | \ +   ((uint32)c << 8) | (uint32)d) + +// a UDP packet header (comes after an IP header). +struct udp { +  uint16 sport; // source port +  uint16 dport; // destination port +  uint16 ulen;  // length, including udp header, not including IP header +  uint16 sum;   // checksum +}; + +// an ARP packet (comes after an Ethernet header). +struct arp { +  uint16 hrd; // format of hardware address +  uint16 pro; // format of protocol address +  uint8  hln; // length of hardware address +  uint8  pln; // length of protocol address +  uint16 op;  // operation + +  char   sha[ETHADDR_LEN]; // sender hardware address +  uint32 sip;              // sender IP address +  char   tha[ETHADDR_LEN]; // target hardware address +  uint32 tip;              // target IP address +} __attribute__((packed)); + +#define ARP_HRD_ETHER 1 // Ethernet + +enum { +  ARP_OP_REQUEST = 1, // requests hw addr given protocol addr +  ARP_OP_REPLY = 2,   // replies a hw addr given protocol addr +}; + +// an DNS packet (comes after an UDP header). +struct dns { +  uint16 id;  // request ID + +  uint8 rd: 1;  // recursion desired +  uint8 tc: 1;  // truncated +  uint8 aa: 1;  // authoritive +  uint8 opcode: 4;  +  uint8 qr: 1;  // query/response +  uint8 rcode: 4; // response code +  uint8 cd: 1;  // checking disabled +  uint8 ad: 1;  // authenticated data +  uint8 z:  1;   +  uint8 ra: 1;  // recursion available +   +  uint16 qdcount; // number of question entries +  uint16 ancount; // number of resource records in answer section +  uint16 nscount; // number of NS resource records in authority section +  uint16 arcount; // number of resource records in additional records +} __attribute__((packed)); + +struct dns_question { +  uint16 qtype; +  uint16 qclass; +} __attribute__((packed)); +   +#define ARECORD (0x0001) +#define QCLASS  (0x0001) + +struct dns_data { +  uint16 type; +  uint16 class; +  uint32 ttl; +  uint16 len; +} __attribute__((packed)); diff --git a/kernel/pci.c b/kernel/pci.c new file mode 100644 index 0000000..5cd2102 --- /dev/null +++ b/kernel/pci.c @@ -0,0 +1,61 @@ +// +// simple PCI-Express initialization, only +// works for qemu and its e1000 card. +// + +#include "types.h" +#include "param.h" +#include "memlayout.h" +#include "riscv.h" +#include "spinlock.h" +#include "proc.h" +#include "defs.h" + +void +pci_init() +{ +  // we'll place the e1000 registers at this address. +  // vm.c maps this range. +  uint64 e1000_regs = 0x40000000L; + +  // qemu -machine virt puts PCIe config space here. +  // vm.c maps this range. +  uint32  *ecam = (uint32 *) 0x30000000L; +   +  // look at each possible PCI device on bus 0. +  for(int dev = 0; dev < 32; dev++){ +    int bus = 0; +    int func = 0; +    int offset = 0; +    uint32 off = (bus << 16) | (dev << 11) | (func << 8) | (offset); +    volatile uint32 *base = ecam + off; +    uint32 id = base[0]; +     +    // 100e:8086 is an e1000 +    if(id == 0x100e8086){ +      // command and status register. +      // bit 0 : I/O access enable +      // bit 1 : memory access enable +      // bit 2 : enable mastering +      base[1] = 7; +      __sync_synchronize(); + +      for(int i = 0; i < 6; i++){ +        uint32 old = base[4+i]; + +        // writing all 1's to the BAR causes it to be +        // replaced with its size. +        base[4+i] = 0xffffffff; +        __sync_synchronize(); + +        base[4+i] = old; +      } + +      // tell the e1000 to reveal its registers at +      // physical address 0x40000000. +      base[4+0] = e1000_regs; + +      e1000_init((uint32*)e1000_regs); +    } +  } +} diff --git a/kernel/plic.c b/kernel/plic.c index 4175db9..5c9d96a 100644 --- a/kernel/plic.c +++ b/kernel/plic.c @@ -14,6 +14,13 @@ plicinit(void)    // set desired IRQ priorities non-zero (otherwise disabled).    *(uint32*)(PLIC + UART0_IRQ*4) = 1;    *(uint32*)(PLIC + VIRTIO0_IRQ*4) = 1; +   +#ifdef LAB_NET +  // PCIE IRQs are 32 to 35 +  for(int irq = 1; irq < 0x35; irq++){ +    *(uint32*)(PLIC + irq*4) = 1; +  } +#endif    }  void @@ -25,6 +32,11 @@ plicinithart(void)    // for the uart and virtio disk.    *(uint32*)PLIC_SENABLE(hart) = (1 << UART0_IRQ) | (1 << VIRTIO0_IRQ); +#ifdef LAB_NET +  // hack to get at next 32 IRQs for e1000 +  *(uint32*)(PLIC_SENABLE(hart)+4) = 0xffffffff; +#endif +      // set this hart's S-mode priority threshold to 0.    *(uint32*)PLIC_SPRIORITY(hart) = 0;  } diff --git a/kernel/spinlock.c b/kernel/spinlock.c index 9840302..266a698 100644 --- a/kernel/spinlock.c +++ b/kernel/spinlock.c @@ -8,12 +8,52 @@  #include "proc.h"  #include "defs.h" +#ifdef LAB_LOCK +#define NLOCK 500 + +static struct spinlock *locks[NLOCK]; +struct spinlock lock_locks; + +void +freelock(struct spinlock *lk) +{ +  acquire(&lock_locks); +  int i; +  for (i = 0; i < NLOCK; i++) { +    if(locks[i] == lk) { +      locks[i] = 0; +      break; +    } +  } +  release(&lock_locks); +} + +static void +findslot(struct spinlock *lk) { +  acquire(&lock_locks); +  int i; +  for (i = 0; i < NLOCK; i++) { +    if(locks[i] == 0) { +      locks[i] = lk; +      release(&lock_locks); +      return; +    } +  } +  panic("findslot"); +} +#endif +  void  initlock(struct spinlock *lk, char *name)  {    lk->name = name;    lk->locked = 0;    lk->cpu = 0; +#ifdef LAB_LOCK +  lk->nts = 0; +  lk->n = 0; +  findslot(lk); +#endif    }  // Acquire the lock. @@ -25,12 +65,21 @@ acquire(struct spinlock *lk)    if(holding(lk))      panic("acquire"); +#ifdef LAB_LOCK +    __sync_fetch_and_add(&(lk->n), 1); +#endif       +    // On RISC-V, sync_lock_test_and_set turns into an atomic swap:    //   a5 = 1    //   s1 = &lk->locked    //   amoswap.w.aq a5, a5, (s1) -  while(__sync_lock_test_and_set(&lk->locked, 1) != 0) -    ; +  while(__sync_lock_test_and_set(&lk->locked, 1) != 0) { +#ifdef LAB_LOCK +    __sync_fetch_and_add(&(lk->nts), 1); +#else +   ; +#endif +  }    // Tell the C compiler and the processor to not move loads or stores    // past this point, to ensure that the critical section's memory @@ -108,3 +157,61 @@ pop_off(void)    if(c->noff == 0 && c->intena)      intr_on();  } + +// Read a shared 32-bit value without holding a lock +int +atomic_read4(int *addr) { +  uint32 val; +  __atomic_load(addr, &val, __ATOMIC_SEQ_CST); +  return val; +} + +#ifdef LAB_LOCK +int +snprint_lock(char *buf, int sz, struct spinlock *lk) +{ +  int n = 0; +  if(lk->n > 0) { +    n = snprintf(buf, sz, "lock: %s: #test-and-set %d #acquire() %d\n", +                 lk->name, lk->nts, lk->n); +  } +  return n; +} + +int +statslock(char *buf, int sz) { +  int n; +  int tot = 0; + +  acquire(&lock_locks); +  n = snprintf(buf, sz, "--- lock kmem/bcache stats\n"); +  for(int i = 0; i < NLOCK; i++) { +    if(locks[i] == 0) +      break; +    if(strncmp(locks[i]->name, "bcache", strlen("bcache")) == 0 || +       strncmp(locks[i]->name, "kmem", strlen("kmem")) == 0) { +      tot += locks[i]->nts; +      n += snprint_lock(buf +n, sz-n, locks[i]); +    } +  } +   +  n += snprintf(buf+n, sz-n, "--- top 5 contended locks:\n"); +  int last = 100000000; +  // stupid way to compute top 5 contended locks +  for(int t = 0; t < 5; t++) { +    int top = 0; +    for(int i = 0; i < NLOCK; i++) { +      if(locks[i] == 0) +        break; +      if(locks[i]->nts > locks[top]->nts && locks[i]->nts < last) { +        top = i; +      } +    } +    n += snprint_lock(buf+n, sz-n, locks[top]); +    last = locks[top]->nts; +  } +  n += snprintf(buf+n, sz-n, "tot= %d\n", tot); +  release(&lock_locks);   +  return n; +} +#endif diff --git a/kernel/syscall.c b/kernel/syscall.c index 8392eb4..172c5ea 100644 --- a/kernel/syscall.c +++ b/kernel/syscall.c @@ -113,6 +113,13 @@ extern uint64 sys_pgaccess(void);  extern uint64 sys_sigalarm(void);  extern uint64 sys_sigreturn(void); +#ifdef LAB_NET +extern uint64 sys_connect(void); +#endif +#ifdef LAB_PGTBL +extern uint64 sys_pgaccess(void); +#endif +  // An array mapping syscall numbers from syscall.h  // to the function that handles the system call.  static uint64 (*syscalls[])(void) = { @@ -185,7 +192,6 @@ static char *syscall_names[] = {  }; -  void  syscall(void)  { diff --git a/kernel/sysfile.c b/kernel/sysfile.c index 16b668c..4b2189a 100644 --- a/kernel/sysfile.c +++ b/kernel/sysfile.c @@ -503,3 +503,29 @@ sys_pipe(void)    }    return 0;  } + + +#ifdef LAB_NET +int +sys_connect(void) +{ +  struct file *f; +  int fd; +  uint32 raddr; +  uint32 rport; +  uint32 lport; + +  argint(0, (int*)&raddr); +  argint(1, (int*)&lport); +  argint(2, (int*)&rport); + +  if(sockalloc(&f, raddr, lport, rport) < 0) +    return -1; +  if((fd=fdalloc(f)) < 0){ +    fileclose(f); +    return -1; +  } + +  return fd; +} +#endif diff --git a/kernel/sysnet.c b/kernel/sysnet.c new file mode 100644 index 0000000..1c48cb3 --- /dev/null +++ b/kernel/sysnet.c @@ -0,0 +1,185 @@ +// +// network system calls. +// + +#include "types.h" +#include "param.h" +#include "memlayout.h" +#include "riscv.h" +#include "spinlock.h" +#include "proc.h" +#include "defs.h" +#include "fs.h" +#include "sleeplock.h" +#include "file.h" +#include "net.h" + +struct sock { +  struct sock *next; // the next socket in the list +  uint32 raddr;      // the remote IPv4 address +  uint16 lport;      // the local UDP port number +  uint16 rport;      // the remote UDP port number +  struct spinlock lock; // protects the rxq +  struct mbufq rxq;  // a queue of packets waiting to be received +}; + +static struct spinlock lock; +static struct sock *sockets; + +void +sockinit(void) +{ +  initlock(&lock, "socktbl"); +} + +int +sockalloc(struct file **f, uint32 raddr, uint16 lport, uint16 rport) +{ +  struct sock *si, *pos; + +  si = 0; +  *f = 0; +  if ((*f = filealloc()) == 0) +    goto bad; +  if ((si = (struct sock*)kalloc()) == 0) +    goto bad; + +  // initialize objects +  si->raddr = raddr; +  si->lport = lport; +  si->rport = rport; +  initlock(&si->lock, "sock"); +  mbufq_init(&si->rxq); +  (*f)->type = FD_SOCK; +  (*f)->readable = 1; +  (*f)->writable = 1; +  (*f)->sock = si; + +  // add to list of sockets +  acquire(&lock); +  pos = sockets; +  while (pos) { +    if (pos->raddr == raddr && +        pos->lport == lport && +	pos->rport == rport) { +      release(&lock); +      goto bad; +    } +    pos = pos->next; +  } +  si->next = sockets; +  sockets = si; +  release(&lock); +  return 0; + +bad: +  if (si) +    kfree((char*)si); +  if (*f) +    fileclose(*f); +  return -1; +} + +void +sockclose(struct sock *si) +{ +  struct sock **pos; +  struct mbuf *m; + +  // remove from list of sockets +  acquire(&lock); +  pos = &sockets; +  while (*pos) { +    if (*pos == si){ +      *pos = si->next; +      break; +    } +    pos = &(*pos)->next; +  } +  release(&lock); + +  // free any pending mbufs +  while (!mbufq_empty(&si->rxq)) { +    m = mbufq_pophead(&si->rxq); +    mbuffree(m); +  } + +  kfree((char*)si); +} + +int +sockread(struct sock *si, uint64 addr, int n) +{ +  struct proc *pr = myproc(); +  struct mbuf *m; +  int len; + +  acquire(&si->lock); +  while (mbufq_empty(&si->rxq) && !pr->killed) { +    sleep(&si->rxq, &si->lock); +  } +  if (pr->killed) { +    release(&si->lock); +    return -1; +  } +  m = mbufq_pophead(&si->rxq); +  release(&si->lock); + +  len = m->len; +  if (len > n) +    len = n; +  if (copyout(pr->pagetable, addr, m->head, len) == -1) { +    mbuffree(m); +    return -1; +  } +  mbuffree(m); +  return len; +} + +int +sockwrite(struct sock *si, uint64 addr, int n) +{ +  struct proc *pr = myproc(); +  struct mbuf *m; + +  m = mbufalloc(MBUF_DEFAULT_HEADROOM); +  if (!m) +    return -1; + +  if (copyin(pr->pagetable, mbufput(m, n), addr, n) == -1) { +    mbuffree(m); +    return -1; +  } +  net_tx_udp(m, si->raddr, si->lport, si->rport); +  return n; +} + +// called by protocol handler layer to deliver UDP packets +void +sockrecvudp(struct mbuf *m, uint32 raddr, uint16 lport, uint16 rport) +{ +  // +  // Find the socket that handles this mbuf and deliver it, waking +  // any sleeping reader. Free the mbuf if there are no sockets +  // registered to handle it. +  // +  struct sock *si; + +  acquire(&lock); +  si = sockets; +  while (si) { +    if (si->raddr == raddr && si->lport == lport && si->rport == rport) +      goto found; +    si = si->next; +  } +  release(&lock); +  mbuffree(m); +  return; + +found: +  acquire(&si->lock); +  mbufq_pushtail(&si->rxq, m); +  wakeup(&si->rxq); +  release(&si->lock); +  release(&lock); +} diff --git a/kernel/trap.c b/kernel/trap.c index bd3b100..7cc69b1 100644 --- a/kernel/trap.c +++ b/kernel/trap.c @@ -79,6 +79,8 @@ usertrap(void)      if(cow_handler(p->pagetable, va) < 0)        goto err;    } else { + +          printf("usertrap(): unexpected scause %p pid=%d\n", r_scause(), p->pid);      printf("            sepc=%p stval=%p\n", r_sepc(), r_stval());    err: @@ -88,6 +90,7 @@ usertrap(void)    if(killed(p))      exit(-1); +      if(which_dev == 2){      // timer interrupt @@ -216,7 +219,13 @@ devintr()        uartintr();      } else if(irq == VIRTIO0_IRQ){        virtio_disk_intr(); -    } else if(irq){ +    } +#ifdef LAB_NET +    else if(irq == E1000_IRQ){ +      e1000_intr(); +    } +#endif +    else if(irq){        printf("unexpected interrupt irq=%d\n", irq);      } diff --git a/kernel/vm.c b/kernel/vm.c index 11f9e0a..be7d042 100644 --- a/kernel/vm.c +++ b/kernel/vm.c @@ -4,6 +4,8 @@  #include "elf.h"  #include "riscv.h"  #include "defs.h" +#include "spinlock.h" +#include "proc.h"  #include "fs.h"  /* @@ -30,6 +32,14 @@ kvmmake(void)    // virtio mmio disk interface    kvmmap(kpgtbl, VIRTIO0, VIRTIO0, PGSIZE, PTE_R | PTE_W); +#ifdef LAB_NET +  // PCI-E ECAM (configuration space), for pci.c +  kvmmap(kpgtbl, 0x30000000L, 0x30000000L, 0x10000000, PTE_R | PTE_W); + +  // pci.c maps the e1000's registers here. +  kvmmap(kpgtbl, 0x40000000L, 0x40000000L, 0x20000, PTE_R | PTE_W); +#endif   +    // PLIC    kvmmap(kpgtbl, PLIC, PLIC, 0x400000, PTE_R | PTE_W); @@ -136,9 +146,8 @@ kvmmap(pagetable_t kpgtbl, uint64 va, uint64 pa, uint64 sz, int perm)  }  // Create PTEs for virtual addresses starting at va that refer to -// physical addresses starting at pa. -// va and size MUST be page-aligned. -// Returns 0 on success, -1 if walk() couldn't +// physical addresses starting at pa. va and size might not +// be page-aligned. Returns 0 on success, -1 if walk() couldn't  // allocate a needed page-table page.  int  mappages(pagetable_t pagetable, uint64 va, uint64 size, uint64 pa, int perm) @@ -146,17 +155,11 @@ mappages(pagetable_t pagetable, uint64 va, uint64 size, uint64 pa, int perm)    uint64 a, last;    pte_t *pte; -  if((va % PGSIZE) != 0) -    panic("mappages: va not aligned"); - -  if((size % PGSIZE) != 0) -    panic("mappages: size not aligned"); -    if(size == 0)      panic("mappages: size"); -  a = va; -  last = va + size - PGSIZE; +  a = PGROUNDDOWN(va); +  last = PGROUNDDOWN(va + size - 1);    for(;;){      if((pte = walk(pagetable, a, 1)) == 0)        return -1; @@ -186,8 +189,10 @@ uvmunmap(pagetable_t pagetable, uint64 va, uint64 npages, int do_free)    for(a = va; a < va + npages*PGSIZE; a += PGSIZE){      if((pte = walk(pagetable, a, 0)) == 0)        panic("uvmunmap: walk"); -    if((*pte & PTE_V) == 0) +    if((*pte & PTE_V) == 0) { +      printf("va=%p pte=%p\n", a, *pte);        panic("uvmunmap: not mapped"); +    }      if(PTE_FLAGS(*pte) == PTE_V)        panic("uvmunmap: not a leaf");      if(do_free){ @@ -402,7 +407,7 @@ int  copyin(pagetable_t pagetable, char *dst, uint64 srcva, uint64 len)  {    uint64 n, va0, pa0; - +      while(len > 0){      va0 = PGROUNDDOWN(srcva);      pa0 = walkaddr(pagetable, va0); | 
