diff options
Diffstat (limited to 'src/vlib/buffer_funcs.h')
| -rw-r--r-- | src/vlib/buffer_funcs.h | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/src/vlib/buffer_funcs.h b/src/vlib/buffer_funcs.h index d8abdf31d79..7ab41567c4d 100644 --- a/src/vlib/buffer_funcs.h +++ b/src/vlib/buffer_funcs.h @@ -1269,6 +1269,143 @@ vlib_buffer_chain_compress (vlib_main_t * vm, (first->flags & VLIB_BUFFER_NEXT_PRESENT)); } +always_inline u32 +vlib_buffer_space_left_at_end (vlib_main_t * vm, vlib_buffer_t * b) +{ + return b->data + VLIB_BUFFER_DATA_SIZE - + ((u8 *) vlib_buffer_get_current (b) + b->current_length); +} + +always_inline u32 +vlib_buffer_chain_linearize (vlib_main_t * vm, vlib_buffer_t * b) +{ + vlib_buffer_t *db = b, *sb, *first = b; + int is_cloned = 0; + u32 bytes_left = 0, data_size; + u16 src_left, dst_left, n_buffers = 1; + u8 *dp, *sp; + u32 to_free = 0; + + if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0)) + return 1; + + data_size = VLIB_BUFFER_DATA_SIZE; + + dst_left = vlib_buffer_space_left_at_end (vm, b); + + while (b->flags & VLIB_BUFFER_NEXT_PRESENT) + { + b = vlib_get_buffer (vm, b->next_buffer); + if (b->n_add_refs > 0) + is_cloned = 1; + bytes_left += b->current_length; + n_buffers++; + } + + /* if buffer is cloned, create completely new chain - unless everything fits + * into one buffer */ + if (is_cloned && bytes_left >= dst_left) + { + u32 len = 0; + u32 space_needed = bytes_left - dst_left; + u32 tail; + + if (vlib_buffer_alloc (vm, &tail, 1) == 0) + return 0; + + ++n_buffers; + len += data_size; + b = vlib_get_buffer (vm, tail); + + while (len < space_needed) + { + u32 bi; + if (vlib_buffer_alloc (vm, &bi, 1) == 0) + { + vlib_buffer_free_one (vm, tail); + return 0; + } + b->flags = VLIB_BUFFER_NEXT_PRESENT; + b->next_buffer = bi; + b = vlib_get_buffer (vm, bi); + len += data_size; + n_buffers++; + } + sb = vlib_get_buffer (vm, first->next_buffer); + to_free = first->next_buffer; + first->next_buffer = tail; + } + else + sb = vlib_get_buffer (vm, first->next_buffer); + + src_left = sb->current_length; + sp = vlib_buffer_get_current (sb); + dp = vlib_buffer_get_tail (db); + + while (bytes_left) + { + u16 bytes_to_copy; + + if (dst_left == 0) + { + if (db != first) + db->current_data = 0; + db->current_length = dp - (u8 *) vlib_buffer_get_current (db); + ASSERT (db->flags & VLIB_BUFFER_NEXT_PRESENT); + db = vlib_get_buffer (vm, db->next_buffer); + dst_left = data_size; + dp = db->data; + } + + while (src_left == 0) + { + ASSERT (sb->flags & VLIB_BUFFER_NEXT_PRESENT); + sb = vlib_get_buffer (vm, sb->next_buffer); + src_left = sb->current_length; + sp = vlib_buffer_get_current (sb); + } + + bytes_to_copy = clib_min (dst_left, src_left); + + if (dp != sp) + { + if (sb == db) + bytes_to_copy = clib_min (bytes_to_copy, sp - dp); + + clib_memcpy (dp, sp, bytes_to_copy); + } + + src_left -= bytes_to_copy; + dst_left -= bytes_to_copy; + dp += bytes_to_copy; + sp += bytes_to_copy; + bytes_left -= bytes_to_copy; + } + if (db != first) + db->current_data = 0; + db->current_length = dp - (u8 *) vlib_buffer_get_current (db); + + if (is_cloned && to_free) + vlib_buffer_free_one (vm, to_free); + else + { + if (db->flags & VLIB_BUFFER_NEXT_PRESENT) + vlib_buffer_free_one (vm, db->next_buffer); + db->flags &= ~VLIB_BUFFER_NEXT_PRESENT; + b = first; + n_buffers = 1; + while (b->flags & VLIB_BUFFER_NEXT_PRESENT) + { + b = vlib_get_buffer (vm, b->next_buffer); + ++n_buffers; + } + } + + first->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID; + + return n_buffers; +} + #endif /* included_vlib_buffer_funcs_h */ /* |