+ return 0;
+}
+
+errno_t
+buf_setupl(buf_t bp, upl_t upl, uint32_t offset)
+{
+ if (!(bp->b_lflags & BL_IOBUF)) {
+ return EINVAL;
+ }
+
+ if (upl) {
+ bp->b_flags |= B_CLUSTER;
+ } else {
+ bp->b_flags &= ~B_CLUSTER;
+ }
+ bp->b_upl = upl;
+ bp->b_uploffset = offset;
+
+ return 0;
+}
+
+buf_t
+buf_clone(buf_t bp, int io_offset, int io_size, void (*iodone)(buf_t, void *), void *arg)
+{
+ buf_t io_bp;
+
+ if (io_offset < 0 || io_size < 0) {
+ return NULL;
+ }
+
+ if ((unsigned)(io_offset + io_size) > (unsigned)bp->b_bcount) {
+ return NULL;
+ }
+
+ if (bp->b_flags & B_CLUSTER) {
+ if (io_offset && ((bp->b_uploffset + io_offset) & PAGE_MASK)) {
+ return NULL;
+ }
+
+ if (((bp->b_uploffset + io_offset + io_size) & PAGE_MASK) && ((io_offset + io_size) < bp->b_bcount)) {
+ return NULL;
+ }
+ }
+ io_bp = alloc_io_buf(bp->b_vp, 0);
+
+ io_bp->b_flags = bp->b_flags & (B_COMMIT_UPL | B_META | B_PAGEIO | B_CLUSTER | B_PHYS | B_RAW | B_ASYNC | B_READ | B_FUA);
+
+ if (iodone) {
+ io_bp->b_transaction = arg;
+ io_bp->b_iodone = iodone;
+ io_bp->b_flags |= B_CALL;
+ }
+ if (bp->b_flags & B_CLUSTER) {
+ io_bp->b_upl = bp->b_upl;
+ io_bp->b_uploffset = bp->b_uploffset + io_offset;
+ } else {
+ io_bp->b_datap = (uintptr_t)(((char *)bp->b_datap) + io_offset);
+ }
+ io_bp->b_bcount = io_size;
+
+ return io_bp;
+}
+
+
+int
+buf_shadow(buf_t bp)
+{
+ if (bp->b_lflags & BL_SHADOW) {
+ return 1;
+ }
+ return 0;
+}
+
+
+buf_t
+buf_create_shadow_priv(buf_t bp, boolean_t force_copy, uintptr_t external_storage, void (*iodone)(buf_t, void *), void *arg)
+{
+ return buf_create_shadow_internal(bp, force_copy, external_storage, iodone, arg, 1);
+}
+
+buf_t
+buf_create_shadow(buf_t bp, boolean_t force_copy, uintptr_t external_storage, void (*iodone)(buf_t, void *), void *arg)
+{
+ return buf_create_shadow_internal(bp, force_copy, external_storage, iodone, arg, 0);
+}
+
+
+static buf_t
+buf_create_shadow_internal(buf_t bp, boolean_t force_copy, uintptr_t external_storage, void (*iodone)(buf_t, void *), void *arg, int priv)
+{
+ buf_t io_bp;
+
+ KERNEL_DEBUG(0xbbbbc000 | DBG_FUNC_START, bp, 0, 0, 0, 0);
+
+ if (!(bp->b_flags & B_META) || (bp->b_lflags & BL_IOBUF)) {
+ KERNEL_DEBUG(0xbbbbc000 | DBG_FUNC_END, bp, 0, 0, 0, 0);
+ return NULL;
+ }
+#ifdef BUF_MAKE_PRIVATE
+ if (bp->b_shadow_ref && bp->b_data_ref == 0 && external_storage == 0) {
+ panic("buf_create_shadow: %p is in the private state (%d, %d)", bp, bp->b_shadow_ref, bp->b_data_ref);
+ }
+#endif
+ io_bp = alloc_io_buf(bp->b_vp, priv);
+
+ io_bp->b_flags = bp->b_flags & (B_META | B_ZALLOC | B_ASYNC | B_READ | B_FUA);
+ io_bp->b_blkno = bp->b_blkno;
+ io_bp->b_lblkno = bp->b_lblkno;
+
+ if (iodone) {
+ io_bp->b_transaction = arg;
+ io_bp->b_iodone = iodone;
+ io_bp->b_flags |= B_CALL;
+ }
+ if (force_copy == FALSE) {
+ io_bp->b_bcount = bp->b_bcount;
+ io_bp->b_bufsize = bp->b_bufsize;
+
+ if (external_storage) {
+ io_bp->b_datap = external_storage;
+#ifdef BUF_MAKE_PRIVATE
+ io_bp->b_data_store = NULL;
+#endif
+ } else {
+ io_bp->b_datap = bp->b_datap;
+#ifdef BUF_MAKE_PRIVATE
+ io_bp->b_data_store = bp;
+#endif
+ }
+ *(buf_t *)(&io_bp->b_orig) = bp;
+
+ lck_mtx_lock_spin(buf_mtxp);
+
+ io_bp->b_lflags |= BL_SHADOW;
+ io_bp->b_shadow = bp->b_shadow;
+ bp->b_shadow = io_bp;
+ bp->b_shadow_ref++;
+
+#ifdef BUF_MAKE_PRIVATE
+ if (external_storage) {
+ io_bp->b_lflags |= BL_EXTERNAL;
+ } else {
+ bp->b_data_ref++;
+ }
+#endif
+ lck_mtx_unlock(buf_mtxp);
+ } else {
+ if (external_storage) {
+#ifdef BUF_MAKE_PRIVATE
+ io_bp->b_lflags |= BL_EXTERNAL;
+#endif
+ io_bp->b_bcount = bp->b_bcount;
+ io_bp->b_bufsize = bp->b_bufsize;
+ io_bp->b_datap = external_storage;
+ } else {
+ allocbuf(io_bp, bp->b_bcount);
+
+ io_bp->b_lflags |= BL_IOBUF_ALLOC;
+ }
+ bcopy((caddr_t)bp->b_datap, (caddr_t)io_bp->b_datap, bp->b_bcount);
+
+#ifdef BUF_MAKE_PRIVATE
+ io_bp->b_data_store = NULL;
+#endif
+ }
+ KERNEL_DEBUG(0xbbbbc000 | DBG_FUNC_END, bp, bp->b_shadow_ref, 0, io_bp, 0);
+
+ return io_bp;
projects / apple / xnu.git / blobdiff