linux-2.4.18-kiobuf.patch

   1 diff -urNp linux-1580/drivers/char/raw.c linux-1620/drivers/char/raw.c
   2 --- linux-1580/drivers/char/raw.c
   3 +++ linux-1620/drivers/char/raw.c
   4 @@ -86,12 +86,6 @@ int raw_open(struct inode *inode, struct
   5                 filp->f_op = &raw_ctl_fops;
   6                 return 0;
   7         }
   8 -
   9 -       if (!filp->f_iobuf) {
  10 -               err = alloc_kiovec(1, &filp->f_iobuf);
  11 -               if (err)
  12 -                       return err;
  13 -       }
  14
  15         down(&raw_devices[minor].mutex);
  16         /*
  17 @@ -295,7 +289,6 @@ ssize_t     rw_raw_dev(int rw, struct file *
  18                    size_t size, loff_t *offp)
  19  {
  20         struct kiobuf * iobuf;
  21 -       int             new_iobuf;
  22         int             err = 0;
  23         unsigned long   blocknr, blocks;
  24         size_t          transferred;
  25 @@ -314,18 +307,10 @@ ssize_t   rw_raw_dev(int rw, struct file *
  26
  27         minor = MINOR(filp->f_dentry->d_inode->i_rdev);
  28
  29 -       new_iobuf = 0;
  30 -       iobuf = filp->f_iobuf;
  31 -       if (test_and_set_bit(0, &filp->f_iobuf_lock)) {
  32 -               /*
  33 -                * A parallel read/write is using the preallocated iobuf
  34 -                * so just run slow and allocate a new one.
  35 -                */
  36 -               err = alloc_kiovec(1, &iobuf);
  37 -               if (err)
  38 -                       goto out;
  39 -               new_iobuf = 1;
  40 -       }
  41 +       err = alloc_kiovec(1, &iobuf);
  42 +       if (err)
  43 +               return err;
  44 +
  45
  46         dev = to_kdev_t(raw_devices[minor].binding->bd_dev);
  47         sector_size = raw_devices[minor].sector_size;
  48 @@ -398,10 +383,6 @@ ssize_t    rw_raw_dev(int rw, struct file *
  49         }
  50
  51   out_free:
  52 -       if (!new_iobuf)
  53 -               clear_bit(0, &filp->f_iobuf_lock);
  54 -       else
  55 -               free_kiovec(1, &iobuf);
  56 - out:
  57 +       free_kiovec(1, &iobuf);
  58         return err;
  59  }
  60 diff -urNp linux-1580/fs/iobuf.c linux-1620/fs/iobuf.c
  61 --- linux-1580/fs/iobuf.c
  62 +++ linux-1620/fs/iobuf.c
  63 @@ -8,8 +8,6 @@
  64
  65  #include <linux/iobuf.h>
  66  #include <linux/slab.h>
  67 -#include <linux/vmalloc.h>
  68 -
  69
  70  static kmem_cache_t *kiobuf_cachep;
  71
  72 @@ -27,6 +25,8 @@ void end_kio_request(struct kiobuf *kiob
  73
  74  static int kiobuf_init(struct kiobuf *iobuf)
  75  {
  76 +       int retval;
  77 +
  78         init_waitqueue_head(&iobuf->wait_queue);
  79         iobuf->array_len = 0;
  80         iobuf->nr_pages = 0;
  81 @@ -35,7 +35,16 @@ static int kiobuf_init(struct kiobuf *io
  82         iobuf->blocks = NULL;
  83         atomic_set(&iobuf->io_count, 0);
  84         iobuf->end_io = NULL;
  85 -       return expand_kiobuf(iobuf, KIO_STATIC_PAGES);
  86 +       iobuf->initialized = 0;
  87 +       retval = expand_kiobuf(iobuf, KIO_STATIC_PAGES);
  88 +       if (retval) return retval;
  89 +       retval = alloc_kiobuf_bhs(iobuf);
  90 +       if (retval) {
  91 +               kfree(iobuf->maplist);
  92 +               return retval;
  93 +       }
  94 +       iobuf->initialized = 1;
  95 +       return 0;
  96  }
  97
  98  int alloc_kiobuf_bhs(struct kiobuf * kiobuf)
  99 @@ -89,6 +98,21 @@ void free_kiobuf_bhs(struct kiobuf * kio
 100         }
 101  }
 102
 103 +void kiobuf_ctor(void * objp, kmem_cache_t * cachep, unsigned long flag)
 104 +{
 105 +       struct kiobuf * iobuf = (struct kiobuf *) objp;
 106 +       kiobuf_init(iobuf);
 107 +}
 108 +
 109 +void kiobuf_dtor(void * objp, kmem_cache_t * cachep, unsigned long flag)
 110 +{
 111 +       struct kiobuf * iobuf = (struct kiobuf *) objp;
 112 +       if (iobuf->initialized) {
 113 +               kfree(iobuf->maplist);
 114 +               free_kiobuf_bhs(iobuf);
 115 +       }
 116 +}
 117 +
 118  int alloc_kiovec(int nr, struct kiobuf **bufp)
 119  {
 120         int i;
 121 @@ -98,10 +122,11 @@ int alloc_kiovec(int nr, struct kiobuf *
 122                 iobuf = kmem_cache_alloc(kiobuf_cachep, GFP_KERNEL);
 123                 if (unlikely(!iobuf))
 124                         goto nomem;
 125 -               if (unlikely(kiobuf_init(iobuf)))
 126 -                       goto nomem2;
 127 -               if (unlikely(alloc_kiobuf_bhs(iobuf)))
 128 -                       goto nomem2;
 129 +               if (unlikely(!iobuf->initialized)) {
 130 +                       /* try again to complete previously failed ctor */
 131 +                       if (unlikely(kiobuf_init(iobuf)))
 132 +                               goto nomem2;
 133 +               }
 134                 bufp[i] = iobuf;
 135         }
 136
 137 @@ -121,11 +146,10 @@ void free_kiovec(int nr, struct kiobuf *
 138
 139         for (i = 0; i < nr; i++) {
 140                 iobuf = bufp[i];
 141 -               if (iobuf->locked)
 142 -                       unlock_kiovec(1, &iobuf);
 143 -               kfree(iobuf->maplist);
 144 -               free_kiobuf_bhs(iobuf);
 145 -               kmem_cache_free(kiobuf_cachep, bufp[i]);
 146 +               init_waitqueue_head(&iobuf->wait_queue);
 147 +               iobuf->io_count.counter = 0;
 148 +               iobuf->end_io = NULL;
 149 +               kmem_cache_free(kiobuf_cachep, iobuf);
 150         }
 151  }
 152
 153 @@ -180,7 +204,7 @@ repeat:
 154  void __init iobuf_cache_init(void)
 155  {
 156         kiobuf_cachep = kmem_cache_create("kiobuf", sizeof(struct kiobuf),
 157 -                                         0, SLAB_HWCACHE_ALIGN, NULL, NULL);
 158 +                                         0, SLAB_HWCACHE_ALIGN, kiobuf_ctor, kiobuf_dtor);
 159         if (!kiobuf_cachep)
 160                 panic("Cannot create kiobuf SLAB cache");
 161  }
 162 diff -urNp linux-1580/include/linux/iobuf.h linux-1620/include/linux/iobuf.h
 163 --- linux-1580/include/linux/iobuf.h
 164 +++ linux-1620/include/linux/iobuf.h
 165 @@ -39,7 +39,8 @@ struct kiobuf
 166         int             offset;         /* Offset to start of valid data */
 167         int             length;         /* Number of valid bytes of data */
 168
 169 -       unsigned int    locked : 1;     /* If set, pages has been locked */
 170 +       unsigned int    locked : 1,     /* If set, pages has been locked */
 171 +                       initialized:1;  /* If set, done initialize */
 172
 173         struct page **  maplist;
 174         struct buffer_head ** bh;