drivers/network/ndisuio/misc.c

   1 /*
   2  * COPYRIGHT:   See COPYING in the top level directory
   3  * PROJECT:     ReactOS NDIS User I/O driver
   4  * FILE:        misc.c
   5  * PURPOSE:     Helper functions
   6  * PROGRAMMERS: Cameron Gutman (cameron.gutman@reactos.org)
   7  */
   8
   9 #include "ndisuio.h"
  10
  11 #define NDEBUG
  12 #include <debug.h>
  13
  14 NDIS_STATUS
  15 AllocateAndChainBuffer(PNDISUIO_ADAPTER_CONTEXT AdapterContext,
  16                        PNDIS_PACKET Packet,
  17                        PVOID Buffer,
  18                        ULONG BufferSize,
  19                        BOOLEAN Front)
  20 {
  21     NDIS_STATUS Status;
  22     PNDIS_BUFFER NdisBuffer;
  23
  24     /* Allocate the NDIS buffer mapping the pool */
  25     NdisAllocateBuffer(&Status,
  26                        &NdisBuffer,
  27                        AdapterContext->BufferPoolHandle,
  28                        Buffer,
  29                        BufferSize);
  30     if (Status != NDIS_STATUS_SUCCESS)
  31     {
  32         DPRINT1("No free buffer descriptors\n");
  33         return Status;
  34     }
  35
  36     if (Front)
  37     {
  38         /* Chain the buffer to front */
  39         NdisChainBufferAtFront(Packet, NdisBuffer);
  40     }
  41     else
  42     {
  43         /* Chain the buffer to back */
  44         NdisChainBufferAtBack(Packet, NdisBuffer);
  45     }
  46
  47     /* Return success */
  48     return NDIS_STATUS_SUCCESS;
  49 }
  50
  51 PNDIS_PACKET
  52 CreatePacketFromPoolBuffer(PNDISUIO_ADAPTER_CONTEXT AdapterContext,
  53                            PVOID Buffer,
  54                            ULONG BufferSize)
  55 {
  56     PNDIS_PACKET Packet;
  57     NDIS_STATUS Status;
  58
  59     /* Allocate a packet descriptor */
  60     NdisAllocatePacket(&Status,
  61                        &Packet,
  62                        AdapterContext->PacketPoolHandle);
  63     if (Status != NDIS_STATUS_SUCCESS)
  64     {
  65         DPRINT1("No free packet descriptors\n");
  66         return NULL;
  67     }
  68
  69     /* Use the helper to chain the buffer */
  70     Status = AllocateAndChainBuffer(AdapterContext, Packet,
  71                                     Buffer, BufferSize, TRUE);
  72     if (Status != NDIS_STATUS_SUCCESS)
  73     {
  74         NdisFreePacket(Packet);
  75         return NULL;
  76     }
  77
  78     /* Return the packet */
  79     return Packet;
  80 }
  81
  82 VOID
  83 CleanupAndFreePacket(PNDIS_PACKET Packet, BOOLEAN FreePool)
  84 {
  85     PNDIS_BUFFER Buffer;
  86     PVOID Data;
  87     ULONG Length;
  88
  89     /* Free each buffer and its backing pool memory */
  90     while (TRUE)
  91     {
  92         /* Unchain each buffer */
  93         NdisUnchainBufferAtFront(Packet, &Buffer);
  94         if (!Buffer)
  95             break;
  96
  97         /* Get the backing memory */
  98         NdisQueryBuffer(Buffer, &Data, &Length);
  99
 100         /* Free the buffer */
 101         NdisFreeBuffer(Buffer);
 102
 103         if (FreePool)
 104         {
 105             /* Free the backing memory */
 106             ExFreePool(Data);
 107         }
 108     }
 109
 110     /* Free the packet descriptor */
 111     NdisFreePacket(Packet);
 112 }
 113
 114 PNDISUIO_ADAPTER_CONTEXT
 115 FindAdapterContextByName(PNDIS_STRING DeviceName)
 116 {
 117     KIRQL OldIrql;
 118     PLIST_ENTRY CurrentEntry;
 119     PNDISUIO_ADAPTER_CONTEXT AdapterContext;
 120
 121     KeAcquireSpinLock(&GlobalAdapterListLock, &OldIrql);
 122     CurrentEntry = GlobalAdapterList.Flink;
 123     while (CurrentEntry != &GlobalAdapterList)
 124     {
 125         AdapterContext = CONTAINING_RECORD(CurrentEntry, NDISUIO_ADAPTER_CONTEXT, ListEntry);
 126
 127         /* Check if the device name matches */
 128         if (RtlEqualUnicodeString(&AdapterContext->DeviceName, DeviceName, TRUE))
 129         {
 130             KeReleaseSpinLock(&GlobalAdapterListLock, OldIrql);
 131             return AdapterContext;
 132         }
 133
 134         CurrentEntry = CurrentEntry->Flink;
 135     }
 136     KeReleaseSpinLock(&GlobalAdapterListLock, OldIrql);
 137
 138     return NULL;
 139 }
 140
 141 VOID
 142 ReferenceAdapterContext(PNDISUIO_ADAPTER_CONTEXT AdapterContext)
 143 {
 144     /* Increment the open count */
 145     AdapterContext->OpenCount++;
 146 }
 147
 148 VOID
 149 DereferenceAdapterContextWithOpenEntry(PNDISUIO_ADAPTER_CONTEXT AdapterContext,
 150                                        PNDISUIO_OPEN_ENTRY OpenEntry)
 151 {
 152     KIRQL OldIrql;
 153
 154     /* Lock the adapter context */
 155     KeAcquireSpinLock(&AdapterContext->Spinlock, &OldIrql);
 156
 157     /* Decrement the open count */
 158     AdapterContext->OpenCount--;
 159
 160     /* Cleanup the open entry if we were given one */
 161     if (OpenEntry != NULL)
 162     {
 163         /* Remove the open entry */
 164         RemoveEntryList(&OpenEntry->ListEntry);
 165
 166         /* Invalidate the FO */
 167         OpenEntry->FileObject->FsContext = NULL;
 168         OpenEntry->FileObject->FsContext2 = NULL;
 169
 170         /* Free the open entry */
 171         ExFreePool(OpenEntry);
 172     }
 173
 174     /* Release the adapter context lock */
 175     KeReleaseSpinLock(&AdapterContext->Spinlock, OldIrql);
 176 }