1.1 --- a/tools/blktap/drivers/Makefile	Fri Feb 16 16:34:28 2007 +0000
     1.2 +++ b/tools/blktap/drivers/Makefile	Fri Feb 16 20:31:27 2007 -0800
     1.3 @@ -5,7 +5,7 @@ INCLUDES += -I.. -I../lib
     1.4  
     1.5  IBIN         = blktapctrl tapdisk
     1.6  QCOW_UTIL    = img2qcow qcow2raw qcow-create
     1.7 -INST_DIR  = /usr/sbin
     1.8 +INST_DIR     = /usr/sbin
     1.9  LIBAIO_DIR   = ../../libaio/src
    1.10  
    1.11  CFLAGS   += -Werror
    1.12 @@ -17,7 +17,7 @@ CFLAGS   += -D_GNU_SOURCE
    1.13  
    1.14  # Get gcc to generate the dependencies for us.
    1.15  CFLAGS   += -Wp,-MD,.$(@F).d
    1.16 -DEPS     = .*.d
    1.17 +DEPS      = .*.d
    1.18  
    1.19  THREADLIB := -lpthread -lz
    1.20  LIBS      := -L. -L.. -L../lib
    1.21 @@ -29,10 +29,10 @@ LIBS      += -L$(XEN_XENSTORE) -lxenstor
    1.22  
    1.23  AIOLIBS   := $(LIBAIO_DIR)/libaio.a
    1.24  
    1.25 -BLK-OBJS  := block-aio.o 
    1.26 -BLK-OBJS  += block-sync.o 
    1.27 +BLK-OBJS  := block-aio.o
    1.28 +BLK-OBJS  += block-sync.o
    1.29  BLK-OBJS  += block-vmdk.o
    1.30 -BLK-OBJS  += block-ram.o 
    1.31 +BLK-OBJS  += block-ram.o
    1.32  BLK-OBJS  += block-qcow.o
    1.33  BLK-OBJS  += aes.o
    1.34  
    1.35 @@ -52,13 +52,13 @@ tapdisk: $(BLK-OBJS) tapdisk.c
    1.36  qcow-util: img2qcow qcow2raw qcow-create
    1.37  
    1.38  img2qcow qcow2raw qcow-create: %: $(BLK-OBJS)
    1.39 -	$(CC) $(CFLAGS) -o $* $(BLK-OBJS) $*.c $(AIOLIBS)  $(LIBS)
    1.40 +	$(CC) $(CFLAGS) -o $* $(BLK-OBJS) $*.c $(AIOLIBS) $(LIBS)
    1.41  
    1.42  install: all
    1.43 -	$(INSTALL_PROG) $(IBIN) $(QCOW_UTIL) $(DESTDIR)$(INST_DIR)
    1.44 +	$(INSTALL_PROG) $(IBIN) $(QCOW_UTIL) $(VHD_UTIL) $(DESTDIR)$(INST_DIR)
    1.45  
    1.46  clean:
    1.47 -	rm -rf *.o *~ $(DEPS) xen TAGS $(IBIN) $(LIB) $(QCOW_UTIL)
    1.48 +	rm -rf *.o *~ $(DEPS) xen TAGS $(IBIN) $(LIB) $(QCOW_UTIL) $(VHD_UTIL)
    1.49  
    1.50  .PHONY: clean install
    1.51  

     2.1 --- a/tools/blktap/drivers/block-aio.c	Fri Feb 16 16:34:28 2007 +0000
     2.2 +++ b/tools/blktap/drivers/block-aio.c	Fri Feb 16 20:31:27 2007 -0800
     2.3 @@ -58,6 +58,7 @@ struct pending_aio {
     2.4  	td_callback_t cb;
     2.5  	int id;
     2.6  	void *private;
     2.7 +	uint64_t lsec;
     2.8  };
     2.9  
    2.10  struct tdaio_state {
    2.11 @@ -139,12 +140,23 @@ static int get_image_info(struct td_stat
    2.12  	return 0;
    2.13  }
    2.14  
    2.15 +static inline void init_fds(struct disk_driver *dd)
    2.16 +{
    2.17 +	int i;
    2.18 +	struct tdaio_state *prv = (struct tdaio_state *)dd->private;
    2.19 +
    2.20 +	for(i = 0; i < MAX_IOFD; i++) 
    2.21 +		dd->io_fd[i] = 0;
    2.22 +
    2.23 +	dd->io_fd[0] = prv->poll_fd;
    2.24 +}
    2.25 +
    2.26  /* Open the disk file and initialize aio state. */
    2.27 -int tdaio_open (struct td_state *s, const char *name)
    2.28 +int tdaio_open (struct disk_driver *dd, const char *name)
    2.29  {
    2.30  	int i, fd, ret = 0;
    2.31 -	struct tdaio_state *prv = (struct tdaio_state *)s->private;
    2.32 -	s->private = prv;
    2.33 +	struct td_state    *s   = dd->td_state;
    2.34 +	struct tdaio_state *prv = (struct tdaio_state *)dd->private;
    2.35  
    2.36  	DPRINTF("block-aio open('%s')", name);
    2.37  	/* Initialize AIO */
    2.38 @@ -194,18 +206,21 @@ int tdaio_open (struct td_state *s, cons
    2.39  
    2.40          prv->fd = fd;
    2.41  
    2.42 +	init_fds(dd);
    2.43  	ret = get_image_info(s, fd);
    2.44 +
    2.45  done:
    2.46  	return ret;	
    2.47  }
    2.48  
    2.49 -int tdaio_queue_read(struct td_state *s, uint64_t sector,
    2.50 -			       int nb_sectors, char *buf, td_callback_t cb,
    2.51 -			       int id, void *private)
    2.52 +int tdaio_queue_read(struct disk_driver *dd, uint64_t sector,
    2.53 +		     int nb_sectors, char *buf, td_callback_t cb,
    2.54 +		     int id, void *private)
    2.55  {
    2.56  	struct   iocb *io;
    2.57  	struct   pending_aio *pio;
    2.58 -	struct   tdaio_state *prv = (struct tdaio_state *)s->private;
    2.59 +	struct   td_state    *s   = dd->td_state;
    2.60 +	struct   tdaio_state *prv = (struct tdaio_state *)dd->private;
    2.61  	int      size    = nb_sectors * s->sector_size;
    2.62  	uint64_t offset  = sector * (uint64_t)s->sector_size;
    2.63  	long     ioidx;
    2.64 @@ -219,22 +234,24 @@ int tdaio_queue_read(struct td_state *s,
    2.65  	pio->cb = cb;
    2.66  	pio->id = id;
    2.67  	pio->private = private;
    2.68 +	pio->lsec = sector;
    2.69  	
    2.70  	io_prep_pread(io, prv->fd, buf, size, offset);
    2.71  	io->data = (void *)ioidx;
    2.72  	
    2.73  	prv->iocb_queue[prv->iocb_queued++] = io;
    2.74 -	
    2.75 +
    2.76  	return 0;
    2.77  }
    2.78  			
    2.79 -int tdaio_queue_write(struct td_state *s, uint64_t sector,
    2.80 -			       int nb_sectors, char *buf, td_callback_t cb,
    2.81 -			       int id, void *private)
    2.82 +int tdaio_queue_write(struct disk_driver *dd, uint64_t sector,
    2.83 +		      int nb_sectors, char *buf, td_callback_t cb,
    2.84 +		      int id, void *private)
    2.85  {
    2.86  	struct   iocb *io;
    2.87  	struct   pending_aio *pio;
    2.88 -	struct   tdaio_state *prv = (struct tdaio_state *)s->private;
    2.89 +	struct   td_state    *s   = dd->td_state;
    2.90 +	struct   tdaio_state *prv = (struct tdaio_state *)dd->private;
    2.91  	int      size    = nb_sectors * s->sector_size;
    2.92  	uint64_t offset  = sector * (uint64_t)s->sector_size;
    2.93  	long     ioidx;
    2.94 @@ -248,19 +265,20 @@ int tdaio_queue_write(struct td_state *s
    2.95  	pio->cb = cb;
    2.96  	pio->id = id;
    2.97  	pio->private = private;
    2.98 +	pio->lsec = sector;
    2.99  	
   2.100  	io_prep_pwrite(io, prv->fd, buf, size, offset);
   2.101  	io->data = (void *)ioidx;
   2.102  	
   2.103  	prv->iocb_queue[prv->iocb_queued++] = io;
   2.104 -	
   2.105 +
   2.106  	return 0;
   2.107  }
   2.108  			
   2.109 -int tdaio_submit(struct td_state *s)
   2.110 +int tdaio_submit(struct disk_driver *dd)
   2.111  {
   2.112  	int ret;
   2.113 -	struct   tdaio_state *prv = (struct tdaio_state *)s->private;
   2.114 +	struct tdaio_state *prv = (struct tdaio_state *)dd->private;
   2.115  
   2.116  	ret = io_submit(prv->aio_ctx, prv->iocb_queued, prv->iocb_queue);
   2.117  	
   2.118 @@ -269,38 +287,24 @@ int tdaio_submit(struct td_state *s)
   2.119  	/* Success case: */
   2.120  	prv->iocb_queued = 0;
   2.121  	
   2.122 -	return ret;
   2.123 +	return 0;
   2.124  }
   2.125  
   2.126 -int *tdaio_get_fd(struct td_state *s)
   2.127 +int tdaio_close(struct disk_driver *dd)
   2.128  {
   2.129 -	struct tdaio_state *prv = (struct tdaio_state *)s->private;
   2.130 -	int *fds, i;
   2.131 -
   2.132 -	fds = malloc(sizeof(int) * MAX_IOFD);
   2.133 -	/*initialise the FD array*/
   2.134 -	for(i=0;i<MAX_IOFD;i++) fds[i] = 0;
   2.135 -
   2.136 -	fds[0] = prv->poll_fd;
   2.137 -
   2.138 -	return fds;	
   2.139 -}
   2.140 -
   2.141 -int tdaio_close(struct td_state *s)
   2.142 -{
   2.143 -	struct tdaio_state *prv = (struct tdaio_state *)s->private;
   2.144 +	struct tdaio_state *prv = (struct tdaio_state *)dd->private;
   2.145  	
   2.146  	io_destroy(prv->aio_ctx);
   2.147  	close(prv->fd);
   2.148 -	
   2.149 +
   2.150  	return 0;
   2.151  }
   2.152  
   2.153 -int tdaio_do_callbacks(struct td_state *s, int sid)
   2.154 +int tdaio_do_callbacks(struct disk_driver *dd, int sid)
   2.155  {
   2.156  	int ret, i, rsp = 0;
   2.157  	struct io_event *ep;
   2.158 -	struct tdaio_state *prv = (struct tdaio_state *)s->private;
   2.159 +	struct tdaio_state *prv = (struct tdaio_state *)dd->private;
   2.160  
   2.161  	/* Non-blocking test for completed io. */
   2.162  	ret = io_getevents(prv->aio_ctx, 0, MAX_AIO_REQS, prv->aio_events,
   2.163 @@ -311,22 +315,34 @@ int tdaio_do_callbacks(struct td_state *
   2.164  		struct pending_aio *pio;
   2.165  		
   2.166  		pio = &prv->pending_aio[(long)io->data];
   2.167 -		rsp += pio->cb(s, ep->res == io->u.c.nbytes ? 0 : 1,
   2.168 +		rsp += pio->cb(dd, ep->res == io->u.c.nbytes ? 0 : 1,
   2.169 +			       pio->lsec, io->u.c.nbytes >> 9, 
   2.170  			       pio->id, pio->private);
   2.171  
   2.172  		prv->iocb_free[prv->iocb_free_count++] = io;
   2.173  	}
   2.174  	return rsp;
   2.175  }
   2.176 -	
   2.177 +
   2.178 +int tdaio_has_parent(struct disk_driver *dd)
   2.179 +{
   2.180 +	return 0;
   2.181 +}
   2.182 +
   2.183 +int tdaio_get_parent(struct disk_driver *dd, struct disk_driver *parent)
   2.184 +{
   2.185 +	return -EINVAL;
   2.186 +}
   2.187 +
   2.188  struct tap_disk tapdisk_aio = {
   2.189 -	"tapdisk_aio",
   2.190 -	sizeof(struct tdaio_state),
   2.191 -	tdaio_open,
   2.192 -	tdaio_queue_read,
   2.193 -	tdaio_queue_write,
   2.194 -	tdaio_submit,
   2.195 -	tdaio_get_fd,
   2.196 -	tdaio_close,
   2.197 -	tdaio_do_callbacks,
   2.198 +	.disk_type          = "tapdisk_aio",
   2.199 +	.private_data_size  = sizeof(struct tdaio_state),
   2.200 +	.td_open            = tdaio_open,
   2.201 +	.td_queue_read      = tdaio_queue_read,
   2.202 +	.td_queue_write     = tdaio_queue_write,
   2.203 +	.td_submit          = tdaio_submit,
   2.204 +	.td_has_parent      = tdaio_has_parent,
   2.205 +	.td_get_parent      = tdaio_get_parent,
   2.206 +	.td_close           = tdaio_close,
   2.207 +	.td_do_callbacks    = tdaio_do_callbacks,
   2.208  };

     3.1 --- a/tools/blktap/drivers/block-qcow.c	Fri Feb 16 16:34:28 2007 +0000
     3.2 +++ b/tools/blktap/drivers/block-qcow.c	Fri Feb 16 20:31:27 2007 -0800
     3.3 @@ -55,7 +55,6 @@
     3.4  
     3.5  /******AIO DEFINES******/
     3.6  #define REQUEST_ASYNC_FD 1
     3.7 -#define MAX_QCOW_IDS  0xFFFF
     3.8  #define MAX_AIO_REQS (MAX_REQUESTS * MAX_SEGMENTS_PER_REQ)
     3.9  
    3.10  struct pending_aio {
    3.11 @@ -65,7 +64,6 @@ struct pending_aio {
    3.12  	int nb_sectors;
    3.13  	char *buf;
    3.14  	uint64_t sector;
    3.15 -	int qcow_idx;
    3.16  };
    3.17  
    3.18  #define IOCB_IDX(_s, _io) ((_io) - (_s)->iocb_list)
    3.19 @@ -115,9 +113,9 @@ typedef struct QCowHeader_ext {
    3.20  struct tdqcow_state {
    3.21          int fd;                        /*Main Qcow file descriptor */
    3.22  	uint64_t fd_end;               /*Store a local record of file length */
    3.23 -	int bfd;                       /*Backing file descriptor*/
    3.24  	char *name;                    /*Record of the filename*/
    3.25 -	int poll_pipe[2];              /*dummy fd for polling on */
    3.26 +	uint32_t backing_file_size;
    3.27 +	uint64_t backing_file_offset;
    3.28  	int encrypted;                 /*File contents are encrypted or plain*/
    3.29  	int cluster_bits;              /*Determines length of cluster as 
    3.30  					*indicated by file hdr*/
    3.31 @@ -149,7 +147,6 @@ struct tdqcow_state {
    3.32  	AES_KEY aes_decrypt_key;       /*AES key*/
    3.33          /* libaio state */
    3.34          io_context_t       aio_ctx;
    3.35 -	int		   nr_reqs [MAX_QCOW_IDS];
    3.36          struct iocb        iocb_list  [MAX_AIO_REQS];
    3.37          struct iocb       *iocb_free  [MAX_AIO_REQS];
    3.38          struct pending_aio pending_aio[MAX_AIO_REQS];
    3.39 @@ -162,10 +159,11 @@ struct tdqcow_state {
    3.40  
    3.41  static int decompress_cluster(struct tdqcow_state *s, uint64_t cluster_offset);
    3.42  
    3.43 -static int init_aio_state(struct td_state *bs)
    3.44 +static int init_aio_state(struct disk_driver *dd)
    3.45  {
    3.46          int i;
    3.47 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
    3.48 +	struct td_state     *bs = dd->td_state;
    3.49 +	struct tdqcow_state  *s = (struct tdqcow_state *)dd->private;
    3.50          long     ioidx;
    3.51  
    3.52          /*Initialize Locking bitmap*/
    3.53 @@ -202,8 +200,7 @@ static int init_aio_state(struct td_stat
    3.54  
    3.55          for (i=0;i<MAX_AIO_REQS;i++)
    3.56                  s->iocb_free[i] = &s->iocb_list[i];
    3.57 -	for (i=0;i<MAX_QCOW_IDS;i++)
    3.58 -		s->nr_reqs[i] = 0;
    3.59 +
    3.60          DPRINTF("AIO state initialised\n");
    3.61  
    3.62          return 0;
    3.63 @@ -238,7 +235,10 @@ static uint32_t gen_cksum(char *ptr, int
    3.64  
    3.65  	if(!md) return 0;
    3.66  
    3.67 -	if (MD5((unsigned char *)ptr, len, md) != md) return 0;
    3.68 +	if (MD5((unsigned char *)ptr, len, md) != md) {
    3.69 +		free(md);
    3.70 +		return 0;
    3.71 +	}
    3.72  
    3.73  	memcpy(&ret, md, sizeof(uint32_t));
    3.74  	free(md);
    3.75 @@ -247,26 +247,42 @@ static uint32_t gen_cksum(char *ptr, int
    3.76  
    3.77  static int get_filesize(char *filename, uint64_t *size, struct stat *st)
    3.78  {
    3.79 -	int blockfd;
    3.80 +	int fd;
    3.81 +	QCowHeader header;
    3.82  
    3.83  	/*Set to the backing file size*/
    3.84 +	fd = open(filename, O_RDONLY);
    3.85 +	if (fd < 0)
    3.86 +		return -1;
    3.87 +	if (read(fd, &header, sizeof(header)) < sizeof(header)) {
    3.88 +		close(fd);
    3.89 +		return -1;
    3.90 +	}
    3.91 +	close(fd);
    3.92 +	
    3.93 +	be32_to_cpus(&header.magic);
    3.94 +	be64_to_cpus(&header.size);
    3.95 +	if (header.magic == QCOW_MAGIC) {
    3.96 +		*size = header.size >> SECTOR_SHIFT;
    3.97 +		return 0;
    3.98 +	}
    3.99 +
   3.100  	if(S_ISBLK(st->st_mode)) {
   3.101 -		blockfd = open(filename, O_RDONLY);
   3.102 -		if (blockfd < 0)
   3.103 +		fd = open(filename, O_RDONLY);
   3.104 +		if (fd < 0)
   3.105  			return -1;
   3.106 -		if (ioctl(blockfd,BLKGETSIZE,size)!=0) {
   3.107 +		if (ioctl(fd,BLKGETSIZE,size)!=0) {
   3.108  			printf("Unable to get Block device size\n");
   3.109 -			close(blockfd);
   3.110 +			close(fd);
   3.111  			return -1;
   3.112  		}
   3.113 -		close(blockfd);
   3.114 +		close(fd);
   3.115  	} else *size = (st->st_size >> SECTOR_SHIFT);	
   3.116  	return 0;
   3.117  }
   3.118  
   3.119 -static int qcow_set_key(struct td_state *bs, const char *key)
   3.120 +static int qcow_set_key(struct tdqcow_state *s, const char *key)
   3.121  {
   3.122 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.123  	uint8_t keybuf[16];
   3.124  	int len, i;
   3.125  	
   3.126 @@ -306,10 +322,9 @@ static int qcow_set_key(struct td_state 
   3.127  	return 0;
   3.128  }
   3.129  
   3.130 -static int async_read(struct tdqcow_state *s, int fd, int size, 
   3.131 -		     uint64_t offset,
   3.132 -		     char *buf, td_callback_t cb,
   3.133 -		     int id, uint64_t sector, int qcow_idx, void *private)
   3.134 +static int async_read(struct tdqcow_state *s, int size, 
   3.135 +		      uint64_t offset, char *buf, td_callback_t cb,
   3.136 +		      int id, uint64_t sector, void *private)
   3.137  {
   3.138          struct   iocb *io;
   3.139          struct   pending_aio *pio;
   3.140 @@ -325,9 +340,8 @@ static int async_read(struct tdqcow_stat
   3.141  	pio->nb_sectors = size/512;
   3.142  	pio->buf = buf;
   3.143  	pio->sector = sector;
   3.144 -	pio->qcow_idx = qcow_idx;
   3.145  
   3.146 -        io_prep_pread(io, fd, buf, size, offset);
   3.147 +        io_prep_pread(io, s->fd, buf, size, offset);
   3.148          io->data = (void *)ioidx;
   3.149  
   3.150          s->iocb_queue[s->iocb_queued++] = io;
   3.151 @@ -335,10 +349,9 @@ static int async_read(struct tdqcow_stat
   3.152          return 1;
   3.153  }
   3.154  
   3.155 -static int async_write(struct tdqcow_state *s, int fd, int size, 
   3.156 -		     uint64_t offset,
   3.157 -		     char *buf, td_callback_t cb,
   3.158 -		      int id, uint64_t sector, int qcow_idx, void *private)
   3.159 +static int async_write(struct tdqcow_state *s, int size,
   3.160 +		       uint64_t offset, char *buf, td_callback_t cb,
   3.161 +		       int id, uint64_t sector, void *private)
   3.162  {
   3.163          struct   iocb *io;
   3.164          struct   pending_aio *pio;
   3.165 @@ -354,9 +367,8 @@ static int async_write(struct tdqcow_sta
   3.166  	pio->nb_sectors = size/512;
   3.167  	pio->buf = buf;
   3.168  	pio->sector = sector;
   3.169 -	pio->qcow_idx = qcow_idx;
   3.170  
   3.171 -        io_prep_pwrite(io, fd, buf, size, offset);
   3.172 +        io_prep_pwrite(io, s->fd, buf, size, offset);
   3.173          io->data = (void *)ioidx;
   3.174  
   3.175          s->iocb_queue[s->iocb_queued++] = io;
   3.176 @@ -383,17 +395,6 @@ static void aio_unlock(struct tdqcow_sta
   3.177  	return;
   3.178  }
   3.179  
   3.180 -/*TODO - Use a freelist*/
   3.181 -static int get_free_idx(struct tdqcow_state *s)
   3.182 -{
   3.183 -	int i;
   3.184 -	
   3.185 -	for(i = 0; i < MAX_QCOW_IDS; i++) {
   3.186 -		if(s->nr_reqs[i] == 0) return i;
   3.187 -	}
   3.188 -	return -1;
   3.189 -}
   3.190 -
   3.191  /* 
   3.192   * The crypt function is compatible with the linux cryptoloop
   3.193   * algorithm for < 4 GB images. NOTE: out_buf == in_buf is
   3.194 @@ -425,23 +426,23 @@ static int qtruncate(int fd, off_t lengt
   3.195  {
   3.196  	int ret, i; 
   3.197  	int current = 0, rem = 0;
   3.198 -	int sectors = (length + DEFAULT_SECTOR_SIZE - 1)/DEFAULT_SECTOR_SIZE;
   3.199 +	uint64_t sectors;
   3.200  	struct stat st;
   3.201 -	char buf[DEFAULT_SECTOR_SIZE];
   3.202 +	char *buf;
   3.203  
   3.204  	/* If length is greater than the current file len
   3.205  	 * we synchronously write zeroes to the end of the 
   3.206  	 * file, otherwise we truncate the length down
   3.207  	 */
   3.208 -	memset(buf, 0x00, DEFAULT_SECTOR_SIZE);
   3.209  	ret = fstat(fd, &st);
   3.210 -	if (ret == -1)
   3.211 +	if (ret == -1) 
   3.212  		return -1;
   3.213  	if (S_ISBLK(st.st_mode))
   3.214  		return 0;
   3.215 -
   3.216 +	
   3.217 +	sectors = (length + DEFAULT_SECTOR_SIZE - 1)/DEFAULT_SECTOR_SIZE;
   3.218  	current = (st.st_size + DEFAULT_SECTOR_SIZE - 1)/DEFAULT_SECTOR_SIZE;
   3.219 -	rem = st.st_size % DEFAULT_SECTOR_SIZE;
   3.220 +	rem     = st.st_size % DEFAULT_SECTOR_SIZE;
   3.221  
   3.222  	/* If we are extending this file, we write zeros to the end --
   3.223  	 * this tries to ensure that the extents allocated wind up being
   3.224 @@ -449,28 +450,40 @@ static int qtruncate(int fd, off_t lengt
   3.225  	 */
   3.226  	if(st.st_size < sectors * DEFAULT_SECTOR_SIZE) {
   3.227  		/*We are extending the file*/
   3.228 +		if ((ret = posix_memalign((void **)&buf, 
   3.229 +					  512, DEFAULT_SECTOR_SIZE))) {
   3.230 +			DPRINTF("posix_memalign failed: %d\n", ret);
   3.231 +			return -1;
   3.232 +		}
   3.233 +		memset(buf, 0x00, DEFAULT_SECTOR_SIZE);
   3.234  		if (lseek(fd, 0, SEEK_END)==-1) {
   3.235 -			fprintf(stderr, 
   3.236 -				"Lseek EOF failed (%d), internal error\n",
   3.237 +			DPRINTF("Lseek EOF failed (%d), internal error\n",
   3.238  				errno);
   3.239 +			free(buf);
   3.240  			return -1;
   3.241  		}
   3.242  		if (rem) {
   3.243  			ret = write(fd, buf, rem);
   3.244 -			if (ret != rem)
   3.245 +			if (ret != rem) {
   3.246 +				DPRINTF("write failed: ret = %d, err = %s\n",
   3.247 +					ret, strerror(errno));
   3.248 +				free(buf);
   3.249  				return -1;
   3.250 +			}
   3.251  		}
   3.252  		for (i = current; i < sectors; i++ ) {
   3.253  			ret = write(fd, buf, DEFAULT_SECTOR_SIZE);
   3.254 -			if (ret != DEFAULT_SECTOR_SIZE)
   3.255 +			if (ret != DEFAULT_SECTOR_SIZE) {
   3.256 +				DPRINTF("write failed: ret = %d, err = %s\n",
   3.257 +					ret, strerror(errno));
   3.258 +				free(buf);
   3.259  				return -1;
   3.260 +			}
   3.261  		}
   3.262 -		
   3.263 +		free(buf);
   3.264  	} else if(sparse && (st.st_size > sectors * DEFAULT_SECTOR_SIZE))
   3.265 -		if (ftruncate(fd, sectors * DEFAULT_SECTOR_SIZE)==-1) {
   3.266 -			fprintf(stderr,
   3.267 -				"Ftruncate failed (%d), internal error\n",
   3.268 -                                errno);
   3.269 +		if (ftruncate(fd, (off_t)sectors * DEFAULT_SECTOR_SIZE)==-1) {
   3.270 +			DPRINTF("Ftruncate failed (%s)\n", strerror(errno));
   3.271  			return -1;
   3.272  		}
   3.273  	return 0;
   3.274 @@ -490,12 +503,11 @@ static int qtruncate(int fd, off_t lengt
   3.275   *
   3.276   * return 0 if not allocated.
   3.277   */
   3.278 -static uint64_t get_cluster_offset(struct td_state *bs,
   3.279 +static uint64_t get_cluster_offset(struct tdqcow_state *s,
   3.280                                     uint64_t offset, int allocate,
   3.281                                     int compressed_size,
   3.282                                     int n_start, int n_end)
   3.283  {
   3.284 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.285  	int min_index, i, j, l1_index, l2_index, l2_sector, l1_sector;
   3.286  	char *tmp_ptr, *tmp_ptr2, *l2_ptr, *l1_ptr;
   3.287  	uint64_t l2_offset, *l2_table, cluster_offset, tmp;
   3.288 @@ -550,8 +562,10 @@ static uint64_t get_cluster_offset(struc
   3.289  		 * entry is written before blocks.
   3.290  		 */
   3.291  		lseek(s->fd, s->l1_table_offset + (l1_sector << 12), SEEK_SET);
   3.292 -		if (write(s->fd, tmp_ptr, 4096) != 4096)
   3.293 +		if (write(s->fd, tmp_ptr, 4096) != 4096) {
   3.294 +			free(tmp_ptr);
   3.295  		 	return 0;
   3.296 +		}
   3.297  		free(tmp_ptr);
   3.298  
   3.299  		new_l2_table = 1;
   3.300 @@ -716,9 +730,10 @@ found:
   3.301  	return cluster_offset;
   3.302  }
   3.303  
   3.304 -static void init_cluster_cache(struct td_state *bs)
   3.305 +static void init_cluster_cache(struct disk_driver *dd)
   3.306  {
   3.307 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.308 +	struct td_state     *bs = dd->td_state;
   3.309 +	struct tdqcow_state *s  = (struct tdqcow_state *)dd->private;
   3.310  	uint32_t count = 0;
   3.311  	int i, cluster_entries;
   3.312  
   3.313 @@ -727,22 +742,20 @@ static void init_cluster_cache(struct td
   3.314  		cluster_entries, s->cluster_size);
   3.315  
   3.316  	for (i = 0; i < bs->size; i += cluster_entries) {
   3.317 -		if (get_cluster_offset(bs, i << 9, 0, 0, 0, 1)) count++;
   3.318 +		if (get_cluster_offset(s, i << 9, 0, 0, 0, 1)) count++;
   3.319  		if (count >= L2_CACHE_SIZE) return;
   3.320  	}
   3.321  	DPRINTF("Finished cluster initialisation, added %d entries\n", count);
   3.322  	return;
   3.323  }
   3.324  
   3.325 -static int qcow_is_allocated(struct td_state *bs, int64_t sector_num, 
   3.326 +static int qcow_is_allocated(struct tdqcow_state *s, int64_t sector_num,
   3.327                               int nb_sectors, int *pnum)
   3.328  {
   3.329 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.330 -
   3.331  	int index_in_cluster, n;
   3.332  	uint64_t cluster_offset;
   3.333  
   3.334 -	cluster_offset = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0);
   3.335 +	cluster_offset = get_cluster_offset(s, sector_num << 9, 0, 0, 0, 0);
   3.336  	index_in_cluster = sector_num & (s->cluster_sectors - 1);
   3.337  	n = s->cluster_sectors - index_in_cluster;
   3.338  	if (n > nb_sectors)
   3.339 @@ -800,11 +813,23 @@ static int decompress_cluster(struct tdq
   3.340  	return 0;
   3.341  }
   3.342  
   3.343 +static inline void init_fds(struct disk_driver *dd)
   3.344 +{
   3.345 +	int i;
   3.346 +	struct tdqcow_state *s = (struct tdqcow_state *)dd->private;
   3.347 +
   3.348 +	for(i = 0; i < MAX_IOFD; i++) 
   3.349 +		dd->io_fd[i] = 0;
   3.350 +
   3.351 +	dd->io_fd[0] = s->poll_fd;
   3.352 +}
   3.353 +
   3.354  /* Open the disk file and initialize qcow state. */
   3.355 -int tdqcow_open (struct td_state *bs, const char *name)
   3.356 +int tdqcow_open (struct disk_driver *dd, const char *name)
   3.357  {
   3.358  	int fd, len, i, shift, ret, size, l1_table_size;
   3.359 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.360 +	struct td_state     *bs = dd->td_state;
   3.361 +	struct tdqcow_state *s  = (struct tdqcow_state *)dd->private;
   3.362  	char *buf;
   3.363  	QCowHeader *header;
   3.364  	QCowHeader_ext *exthdr;
   3.365 @@ -812,10 +837,6 @@ int tdqcow_open (struct td_state *bs, co
   3.366  	uint64_t final_cluster = 0;
   3.367  
   3.368   	DPRINTF("QCOW: Opening %s\n",name);
   3.369 -	/* set up a pipe so that we can hand back a poll fd that won't fire.*/
   3.370 -	ret = pipe(s->poll_pipe);
   3.371 -	if (ret != 0)
   3.372 -		return (0 - errno);
   3.373  
   3.374  	fd = open(name, O_RDWR | O_DIRECT | O_LARGEFILE);
   3.375  	if (fd < 0) {
   3.376 @@ -826,7 +847,7 @@ int tdqcow_open (struct td_state *bs, co
   3.377  	s->fd = fd;
   3.378  	asprintf(&s->name,"%s", name);
   3.379  
   3.380 -	ASSERT(sizeof(header) < 512);
   3.381 +	ASSERT(sizeof(QCowHeader) + sizeof(QCowHeader_ext) < 512);
   3.382  
   3.383  	ret = posix_memalign((void **)&buf, 512, 512);
   3.384  	if (ret != 0) goto fail;
   3.385 @@ -861,7 +882,9 @@ int tdqcow_open (struct td_state *bs, co
   3.386  	s->cluster_alloc = s->l2_size;
   3.387  	bs->size = header->size / 512;
   3.388  	s->cluster_offset_mask = (1LL << (63 - s->cluster_bits)) - 1;
   3.389 -	
   3.390 +	s->backing_file_offset = header->backing_file_offset;
   3.391 +	s->backing_file_size   = header->backing_file_size;
   3.392 +
   3.393  	/* read the level 1 table */
   3.394  	shift = s->cluster_bits + s->l2_bits;
   3.395  	s->l1_size = (header->size + (1LL << shift) - 1) >> shift;
   3.396 @@ -887,7 +910,7 @@ int tdqcow_open (struct td_state *bs, co
   3.397  	if (read(fd, s->l1_table, l1_table_size) != l1_table_size)
   3.398  		goto fail;
   3.399  
   3.400 -	for(i = 0;i < s->l1_size; i++) {
   3.401 +	for(i = 0; i < s->l1_size; i++) {
   3.402  		//be64_to_cpus(&s->l1_table[i]);
   3.403  		//DPRINTF("L1[%d] => %llu\n", i, s->l1_table[i]);
   3.404  		if (s->l1_table[i] > final_cluster)
   3.405 @@ -907,41 +930,15 @@ int tdqcow_open (struct td_state *bs, co
   3.406  	if(ret != 0) goto fail;
   3.407  	s->cluster_cache_offset = -1;
   3.408  
   3.409 -	/* read the backing file name */
   3.410 -	s->bfd = -1;
   3.411 -	if (header->backing_file_offset != 0) {
   3.412 -		DPRINTF("Reading backing file data\n");
   3.413 -		len = header->backing_file_size;
   3.414 -		if (len > 1023)
   3.415 -			len = 1023;
   3.416 -
   3.417 -                /*TODO - Fix read size for O_DIRECT and use original fd!*/
   3.418 -		fd = open(name, O_RDONLY | O_LARGEFILE);
   3.419 -
   3.420 -		lseek(fd, header->backing_file_offset, SEEK_SET);
   3.421 -		if (read(fd, bs->backing_file, len) != len)
   3.422 -			goto fail;
   3.423 -		bs->backing_file[len] = '\0';
   3.424 -		close(fd);
   3.425 -		/***********************************/
   3.426 -
   3.427 -		/*Open backing file*/
   3.428 -		fd = open(bs->backing_file, O_RDONLY | O_DIRECT | O_LARGEFILE);
   3.429 -		if (fd < 0) {
   3.430 -			DPRINTF("Unable to open backing file: %s\n",
   3.431 -				bs->backing_file);
   3.432 -			goto fail;
   3.433 -		}
   3.434 -		s->bfd = fd;
   3.435 +	if (s->backing_file_offset != 0)
   3.436  		s->cluster_alloc = 1; /*Cannot use pre-alloc*/
   3.437 -	}
   3.438  
   3.439          bs->sector_size = 512;
   3.440          bs->info = 0;
   3.441  	
   3.442  	/*Detect min_cluster_alloc*/
   3.443  	s->min_cluster_alloc = 1; /*Default*/
   3.444 -	if (s->bfd == -1 && (s->l1_table_offset % 4096 == 0) ) {
   3.445 +	if (s->backing_file_offset == 0 && s->l1_table_offset % 4096 == 0) {
   3.446  		/*We test to see if the xen magic # exists*/
   3.447  		exthdr = (QCowHeader_ext *)(buf + sizeof(QCowHeader));
   3.448  		be32_to_cpus(&exthdr->xmagic);
   3.449 @@ -962,10 +959,11 @@ int tdqcow_open (struct td_state *bs, co
   3.450  	}
   3.451  
   3.452   end_xenhdr:
   3.453 -	if (init_aio_state(bs)!=0) {
   3.454 +	if (init_aio_state(dd)!=0) {
   3.455  		DPRINTF("Unable to initialise AIO state\n");
   3.456  		goto fail;
   3.457  	}
   3.458 +	init_fds(dd);
   3.459  	s->fd_end = (final_cluster == 0 ? (s->l1_table_offset + l1_table_size) : 
   3.460  				(final_cluster + s->cluster_size));
   3.461  
   3.462 @@ -981,213 +979,145 @@ fail:
   3.463  	return -1;
   3.464  }
   3.465  
   3.466 - int tdqcow_queue_read(struct td_state *bs, uint64_t sector,
   3.467 -			       int nb_sectors, char *buf, td_callback_t cb,
   3.468 -			       int id, void *private)
   3.469 +int tdqcow_queue_read(struct disk_driver *dd, uint64_t sector,
   3.470 +		      int nb_sectors, char *buf, td_callback_t cb,
   3.471 +		      int id, void *private)
   3.472  {
   3.473 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.474 -	int ret = 0, index_in_cluster, n, i, qcow_idx, asubmit = 0;
   3.475 -	uint64_t cluster_offset;
   3.476 +	struct tdqcow_state *s = (struct tdqcow_state *)dd->private;
   3.477 +	int ret = 0, index_in_cluster, n, i, rsp = 0;
   3.478 +	uint64_t cluster_offset, sec, nr_secs;
   3.479 +
   3.480 +	sec     = sector;
   3.481 +	nr_secs = nb_sectors;
   3.482  
   3.483  	/*Check we can get a lock*/
   3.484 -	for (i = 0; i < nb_sectors; i++)
   3.485 -		if (!aio_can_lock(s, sector + i)) {
   3.486 -			DPRINTF("AIO_CAN_LOCK failed [%llu]\n", 
   3.487 -				(long long) sector + i);
   3.488 -			return -EBUSY;
   3.489 -		}
   3.490 -	
   3.491 +	for (i = 0; i < nb_sectors; i++) 
   3.492 +		if (!aio_can_lock(s, sector + i)) 
   3.493 +			return cb(dd, -EBUSY, sector, nb_sectors, id, private);
   3.494 +
   3.495  	/*We store a local record of the request*/
   3.496 -	qcow_idx = get_free_idx(s);
   3.497  	while (nb_sectors > 0) {
   3.498  		cluster_offset = 
   3.499 -			get_cluster_offset(bs, sector << 9, 0, 0, 0, 0);
   3.500 +			get_cluster_offset(s, sector << 9, 0, 0, 0, 0);
   3.501  		index_in_cluster = sector & (s->cluster_sectors - 1);
   3.502  		n = s->cluster_sectors - index_in_cluster;
   3.503  		if (n > nb_sectors)
   3.504  			n = nb_sectors;
   3.505  
   3.506 -		if (s->iocb_free_count == 0 || !aio_lock(s, sector)) {
   3.507 -			DPRINTF("AIO_LOCK or iocb_free_count (%d) failed" 
   3.508 -				"[%llu]\n", s->iocb_free_count, 
   3.509 -				(long long) sector);
   3.510 -			return -ENOMEM;
   3.511 -		}
   3.512 +		if (s->iocb_free_count == 0 || !aio_lock(s, sector)) 
   3.513 +			return cb(dd, -EBUSY, sector, nb_sectors, id, private);
   3.514  		
   3.515 -		if (!cluster_offset && (s->bfd > 0)) {
   3.516 -			s->nr_reqs[qcow_idx]++;
   3.517 -			asubmit += async_read(s, s->bfd, n * 512, sector << 9, 
   3.518 -					      buf, cb, id, sector, 
   3.519 -					      qcow_idx, private);
   3.520 -		} else if(!cluster_offset) {
   3.521 -			memset(buf, 0, 512 * n);
   3.522 +		if(!cluster_offset) {
   3.523  			aio_unlock(s, sector);
   3.524 +			ret = cb(dd, BLK_NOT_ALLOCATED, 
   3.525 +				 sector, n, id, private);
   3.526 +			if (ret == -EBUSY) {
   3.527 +				/* mark remainder of request
   3.528 +				 * as busy and try again later */
   3.529 +				return cb(dd, -EBUSY, sector + n,
   3.530 +					  nb_sectors - n, id, private);
   3.531 +			} else rsp += ret;
   3.532  		} else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
   3.533 +			aio_unlock(s, sector);
   3.534  			if (decompress_cluster(s, cluster_offset) < 0) {
   3.535 -				ret = -1;
   3.536 +				rsp += cb(dd, -EIO, sector, 
   3.537 +					  nb_sectors, id, private);
   3.538  				goto done;
   3.539  			}
   3.540  			memcpy(buf, s->cluster_cache + index_in_cluster * 512, 
   3.541  			       512 * n);
   3.542 -		} else {			
   3.543 -			s->nr_reqs[qcow_idx]++;
   3.544 -			asubmit += async_read(s, s->fd, n * 512, 
   3.545 -					      (cluster_offset + 
   3.546 -					       index_in_cluster * 512), 
   3.547 -					      buf, cb, id, sector, 
   3.548 -					      qcow_idx, private);
   3.549 +			rsp += cb(dd, 0, sector, n, id, private);
   3.550 +		} else {
   3.551 +			async_read(s, n * 512, 
   3.552 +				   (cluster_offset + index_in_cluster * 512),
   3.553 +				   buf, cb, id, sector, private);
   3.554  		}
   3.555  		nb_sectors -= n;
   3.556  		sector += n;
   3.557  		buf += n * 512;
   3.558  	}
   3.559  done:
   3.560 -        /*Callback if no async requests outstanding*/
   3.561 -        if (!asubmit) return cb(bs, ret == -1 ? -1 : 0, id, private);
   3.562 -
   3.563 -	return 0;
   3.564 +	return rsp;
   3.565  }
   3.566  
   3.567 - int tdqcow_queue_write(struct td_state *bs, uint64_t sector,
   3.568 -			       int nb_sectors, char *buf, td_callback_t cb,
   3.569 -			       int id, void *private)
   3.570 +int tdqcow_queue_write(struct disk_driver *dd, uint64_t sector,
   3.571 +		       int nb_sectors, char *buf, td_callback_t cb,
   3.572 +		       int id, void *private)
   3.573  {
   3.574 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.575 -	int ret = 0, index_in_cluster, n, i, qcow_idx, asubmit = 0;
   3.576 -	uint64_t cluster_offset;
   3.577 +	struct tdqcow_state *s = (struct tdqcow_state *)dd->private;
   3.578 +	int ret = 0, index_in_cluster, n, i;
   3.579 +	uint64_t cluster_offset, sec, nr_secs;
   3.580 +
   3.581 +	sec     = sector;
   3.582 +	nr_secs = nb_sectors;
   3.583  
   3.584  	/*Check we can get a lock*/
   3.585  	for (i = 0; i < nb_sectors; i++)
   3.586 -		if (!aio_can_lock(s, sector + i))  {
   3.587 -			DPRINTF("AIO_CAN_LOCK failed [%llu]\n", 
   3.588 -				(long long) (sector + i));
   3.589 -			return -EBUSY;
   3.590 -		}
   3.591 +		if (!aio_can_lock(s, sector + i))  
   3.592 +			return cb(dd, -EBUSY, sector, nb_sectors, id, private);
   3.593  		   
   3.594  	/*We store a local record of the request*/
   3.595 -	qcow_idx = get_free_idx(s);	
   3.596  	while (nb_sectors > 0) {
   3.597  		index_in_cluster = sector & (s->cluster_sectors - 1);
   3.598  		n = s->cluster_sectors - index_in_cluster;
   3.599  		if (n > nb_sectors)
   3.600  			n = nb_sectors;
   3.601  
   3.602 -		if (s->iocb_free_count == 0 || !aio_lock(s, sector)){
   3.603 -			DPRINTF("AIO_LOCK or iocb_free_count (%d) failed" 
   3.604 -				"[%llu]\n", s->iocb_free_count, 
   3.605 -				(long long) sector);
   3.606 -			return -ENOMEM;
   3.607 +		if (s->iocb_free_count == 0 || !aio_lock(s, sector))
   3.608 +			return cb(dd, -EBUSY, sector, nb_sectors, id, private);
   3.609 +
   3.610 +		cluster_offset = get_cluster_offset(s, sector << 9, 1, 0,
   3.611 +						    index_in_cluster, 
   3.612 +						    index_in_cluster+n);
   3.613 +		if (!cluster_offset) {
   3.614 +			DPRINTF("Ooops, no write cluster offset!\n");
   3.615 +			return cb(dd, -EIO, sector, nb_sectors, id, private);
   3.616  		}
   3.617  
   3.618 -		if (!IS_ZERO(buf,n * 512)) {
   3.619 -
   3.620 -			cluster_offset = get_cluster_offset(bs, sector << 9, 
   3.621 -							    1, 0, 
   3.622 -							    index_in_cluster, 
   3.623 -							    index_in_cluster+n
   3.624 -				);
   3.625 -			if (!cluster_offset) {
   3.626 -				DPRINTF("Ooops, no write cluster offset!\n");
   3.627 -				ret = -1;
   3.628 -				goto done;
   3.629 -			}
   3.630 -
   3.631 -			if (s->crypt_method) {
   3.632 -				encrypt_sectors(s, sector, s->cluster_data, 
   3.633 -						(unsigned char *)buf, n, 1,
   3.634 -						&s->aes_encrypt_key);
   3.635 -				s->nr_reqs[qcow_idx]++;
   3.636 -				asubmit += async_write(s, s->fd, n * 512, 
   3.637 -						       (cluster_offset + 
   3.638 -							index_in_cluster*512), 
   3.639 -						       (char *)s->cluster_data,
   3.640 -						       cb, id, sector, 
   3.641 -						       qcow_idx, private);
   3.642 -			} else {
   3.643 -				s->nr_reqs[qcow_idx]++;
   3.644 -				asubmit += async_write(s, s->fd, n * 512, 
   3.645 -						       (cluster_offset + 
   3.646 -							index_in_cluster*512),
   3.647 -						       buf, cb, id, sector, 
   3.648 -						       qcow_idx, private);
   3.649 -			}
   3.650 +		if (s->crypt_method) {
   3.651 +			encrypt_sectors(s, sector, s->cluster_data, 
   3.652 +					(unsigned char *)buf, n, 1,
   3.653 +					&s->aes_encrypt_key);
   3.654 +			async_write(s, n * 512, 
   3.655 +				    (cluster_offset + index_in_cluster*512),
   3.656 +				    (char *)s->cluster_data, cb, id, sector, 
   3.657 +				    private);
   3.658  		} else {
   3.659 -			/*Write data contains zeros, but we must check to see 
   3.660 -			  if cluster already allocated*/
   3.661 -			cluster_offset = get_cluster_offset(bs, sector << 9, 
   3.662 -							    0, 0, 
   3.663 -							    index_in_cluster, 
   3.664 -							    index_in_cluster+n
   3.665 -				);	
   3.666 -			if(cluster_offset) {
   3.667 -				if (s->crypt_method) {
   3.668 -					encrypt_sectors(s, sector, 
   3.669 -							s->cluster_data, 
   3.670 -							(unsigned char *)buf, 
   3.671 -							n, 1,
   3.672 -							&s->aes_encrypt_key);
   3.673 -					s->nr_reqs[qcow_idx]++;
   3.674 -					asubmit += async_write(s, s->fd, 
   3.675 -							       n * 512, 
   3.676 -							       (cluster_offset+
   3.677 -								index_in_cluster * 512), 
   3.678 -							       (char *)s->cluster_data, cb, id, sector, 
   3.679 -							       qcow_idx, private);
   3.680 -				} else {
   3.681 -					s->nr_reqs[qcow_idx]++;
   3.682 -					asubmit += async_write(s, s->fd, n*512,
   3.683 -							       cluster_offset + index_in_cluster * 512, 
   3.684 -							       buf, cb, id, sector, 
   3.685 -							       qcow_idx, private);
   3.686 -				}
   3.687 -			}
   3.688 -			else aio_unlock(s, sector);
   3.689 +			async_write(s, n * 512, 
   3.690 +				    (cluster_offset + index_in_cluster*512),
   3.691 +				    buf, cb, id, sector, private);
   3.692  		}
   3.693 +		
   3.694  		nb_sectors -= n;
   3.695  		sector += n;
   3.696  		buf += n * 512;
   3.697  	}
   3.698  	s->cluster_cache_offset = -1; /* disable compressed cache */
   3.699  
   3.700 -done:
   3.701 -	/*Callback if no async requests outstanding*/
   3.702 -        if (!asubmit) return cb(bs, ret == -1 ? -1 : 0, id, private);
   3.703 -
   3.704  	return 0;
   3.705  }
   3.706   		
   3.707 -int tdqcow_submit(struct td_state *bs)
   3.708 +int tdqcow_submit(struct disk_driver *dd)
   3.709  {
   3.710          int ret;
   3.711 -        struct   tdqcow_state *prv = (struct tdqcow_state *)bs->private;
   3.712 +        struct   tdqcow_state *prv = (struct tdqcow_state *)dd->private;
   3.713  
   3.714 -        ret = io_submit(prv->aio_ctx, prv->iocb_queued, prv->iocb_queue);
   3.715 +	if (!prv->iocb_queued)
   3.716 +		return 0;
   3.717 +
   3.718 +	ret = io_submit(prv->aio_ctx, prv->iocb_queued, prv->iocb_queue);
   3.719  
   3.720          /* XXX: TODO: Handle error conditions here. */
   3.721  
   3.722          /* Success case: */
   3.723          prv->iocb_queued = 0;
   3.724  
   3.725 -        return ret;
   3.726 +        return 0;
   3.727  }
   3.728  
   3.729 -
   3.730 -int *tdqcow_get_fd(struct td_state *bs)
   3.731 +int tdqcow_close(struct disk_driver *dd)
   3.732  {
   3.733 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.734 -	int *fds, i;
   3.735 -
   3.736 -	fds = malloc(sizeof(int) * MAX_IOFD);
   3.737 -	/*initialise the FD array*/
   3.738 -	for(i=0;i<MAX_IOFD;i++) fds[i] = 0;
   3.739 -
   3.740 -	fds[0] = s->poll_fd;
   3.741 -	return fds;
   3.742 -}
   3.743 -
   3.744 -int tdqcow_close(struct td_state *bs)
   3.745 -{
   3.746 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.747 +	struct tdqcow_state *s = (struct tdqcow_state *)dd->private;
   3.748  	uint32_t cksum, out;
   3.749  	int fd, offset;
   3.750  
   3.751 @@ -1203,6 +1133,7 @@ int tdqcow_close(struct td_state *bs)
   3.752  		close(fd);
   3.753  	}
   3.754  
   3.755 +	io_destroy(s->aio_ctx);
   3.756  	free(s->name);
   3.757  	free(s->l1_table);
   3.758  	free(s->l2_cache);
   3.759 @@ -1212,11 +1143,11 @@ int tdqcow_close(struct td_state *bs)
   3.760  	return 0;
   3.761  }
   3.762  
   3.763 -int tdqcow_do_callbacks(struct td_state *s, int sid)
   3.764 +int tdqcow_do_callbacks(struct disk_driver *dd, int sid)
   3.765  {
   3.766          int ret, i, rsp = 0,*ptr;
   3.767          struct io_event *ep;
   3.768 -        struct tdqcow_state *prv = (struct tdqcow_state *)s->private;
   3.769 +        struct tdqcow_state *prv = (struct tdqcow_state *)dd->private;
   3.770  
   3.771          if (sid > MAX_IOFD) return 1;
   3.772  	
   3.773 @@ -1224,25 +1155,24 @@ int tdqcow_do_callbacks(struct td_state 
   3.774          ret = io_getevents(prv->aio_ctx, 0, MAX_AIO_REQS, prv->aio_events,
   3.775                             NULL);
   3.776  
   3.777 -        for (ep=prv->aio_events, i = ret; i-->0; ep++) {
   3.778 +        for (ep = prv->aio_events, i = ret; i-- > 0; ep++) {
   3.779                  struct iocb        *io  = ep->obj;
   3.780                  struct pending_aio *pio;
   3.781  
   3.782                  pio = &prv->pending_aio[(long)io->data];
   3.783  
   3.784  		aio_unlock(prv, pio->sector);
   3.785 -		if (pio->id >= 0) {
   3.786 -			if (prv->crypt_method)
   3.787 -				encrypt_sectors(prv, pio->sector, 
   3.788 -						(unsigned char *)pio->buf, 
   3.789 -						(unsigned char *)pio->buf, 
   3.790 -						pio->nb_sectors, 0, 
   3.791 -						&prv->aes_decrypt_key);
   3.792 -			prv->nr_reqs[pio->qcow_idx]--;
   3.793 -			if (prv->nr_reqs[pio->qcow_idx] == 0) 
   3.794 -			        rsp += pio->cb(s, ep->res == io->u.c.nbytes ? 0 : 1, pio->id, 
   3.795 -					       pio->private);
   3.796 -		} else if (pio->id == -2) free(pio->buf);
   3.797 +
   3.798 +		if (prv->crypt_method)
   3.799 +			encrypt_sectors(prv, pio->sector, 
   3.800 +					(unsigned char *)pio->buf, 
   3.801 +					(unsigned char *)pio->buf, 
   3.802 +					pio->nb_sectors, 0, 
   3.803 +					&prv->aes_decrypt_key);
   3.804 +
   3.805 +		rsp += pio->cb(dd, ep->res == io->u.c.nbytes ? 0 : 1, 
   3.806 +			       pio->sector, pio->nb_sectors,
   3.807 +			       pio->id, pio->private);
   3.808  
   3.809                  prv->iocb_free[prv->iocb_free_count++] = io;
   3.810          }
   3.811 @@ -1250,7 +1180,7 @@ int tdqcow_do_callbacks(struct td_state 
   3.812  }
   3.813  
   3.814  int qcow_create(const char *filename, uint64_t total_size,
   3.815 -                      const char *backing_file, int sparse)
   3.816 +		const char *backing_file, int sparse)
   3.817  {
   3.818  	int fd, header_size, backing_filename_len, l1_size, i;
   3.819  	int shift, length, adjust, flags = 0, ret = 0;
   3.820 @@ -1391,9 +1321,8 @@ int qcow_create(const char *filename, ui
   3.821  	return 0;
   3.822  }
   3.823  
   3.824 -int qcow_make_empty(struct td_state *bs)
   3.825 +int qcow_make_empty(struct tdqcow_state *s)
   3.826  {
   3.827 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.828  	uint32_t l1_length = s->l1_size * sizeof(uint64_t);
   3.829  
   3.830  	memset(s->l1_table, 0, l1_length);
   3.831 @@ -1412,19 +1341,16 @@ int qcow_make_empty(struct td_state *bs)
   3.832  	return 0;
   3.833  }
   3.834  
   3.835 -int qcow_get_cluster_size(struct td_state *bs)
   3.836 +int qcow_get_cluster_size(struct tdqcow_state *s)
   3.837  {
   3.838 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.839 -
   3.840  	return s->cluster_size;
   3.841  }
   3.842  
   3.843  /* XXX: put compressed sectors first, then all the cluster aligned
   3.844     tables to avoid losing bytes in alignment */
   3.845 -int qcow_compress_cluster(struct td_state *bs, int64_t sector_num, 
   3.846 +int qcow_compress_cluster(struct tdqcow_state *s, int64_t sector_num, 
   3.847                            const uint8_t *buf)
   3.848  {
   3.849 -	struct tdqcow_state *s = (struct tdqcow_state *)bs->private;
   3.850  	z_stream strm;
   3.851  	int ret, out_len;
   3.852  	uint8_t *out_buf;
   3.853 @@ -1463,7 +1389,7 @@ int qcow_compress_cluster(struct td_stat
   3.854  		/* could not compress: write normal cluster */
   3.855  		//tdqcow_queue_write(bs, sector_num, buf, s->cluster_sectors);
   3.856  	} else {
   3.857 -		cluster_offset = get_cluster_offset(bs, sector_num << 9, 2, 
   3.858 +		cluster_offset = get_cluster_offset(s, sector_num << 9, 2, 
   3.859                                              out_len, 0, 0);
   3.860  		cluster_offset &= s->cluster_offset_mask;
   3.861  		lseek(s->fd, cluster_offset, SEEK_SET);
   3.862 @@ -1477,15 +1403,54 @@ int qcow_compress_cluster(struct td_stat
   3.863  	return 0;
   3.864  }
   3.865  
   3.866 +int tdqcow_has_parent(struct disk_driver *dd)
   3.867 +{
   3.868 +	struct tdqcow_state *s = (struct tdqcow_state *)dd->private;
   3.869 +	return (s->backing_file_offset ? 1 : 0);
   3.870 +}
   3.871 +
   3.872 +int tdqcow_get_parent(struct disk_driver *cdd, struct disk_driver *pdd)
   3.873 +{
   3.874 +	off_t off;
   3.875 +	char *buf, *filename;
   3.876 +	int len, secs, ret = -1;
   3.877 +	struct tdqcow_state *child  = (struct tdqcow_state *)cdd->private;
   3.878 +
   3.879 +	if (!child->backing_file_offset)
   3.880 +		return -1;
   3.881 +
   3.882 +	/* read the backing file name */
   3.883 +	len  = child->backing_file_size;
   3.884 +	off  = child->backing_file_offset - (child->backing_file_offset % 512);
   3.885 +	secs = (len + (child->backing_file_offset - off) + 511) >> 9;
   3.886 +
   3.887 +	if (posix_memalign((void **)&buf, 512, secs << 9)) 
   3.888 +		return -1;
   3.889 +
   3.890 +	if (lseek(child->fd, off, SEEK_SET) == (off_t)-1)
   3.891 +		goto out;
   3.892 +
   3.893 +	if (read(child->fd, buf, secs << 9) != secs << 9)
   3.894 +		goto out;
   3.895 +	filename      = buf + (child->backing_file_offset - off);
   3.896 +	filename[len] = '\0';
   3.897 +
   3.898 +	/*Open backing file*/
   3.899 +	ret = tdqcow_open(pdd, filename);
   3.900 + out:
   3.901 +	free(buf);
   3.902 +	return ret;
   3.903 +}
   3.904 +
   3.905  struct tap_disk tapdisk_qcow = {
   3.906 -	"tapdisk_qcow",
   3.907 -	sizeof(struct tdqcow_state),
   3.908 -	tdqcow_open,
   3.909 -	tdqcow_queue_read,
   3.910 -	tdqcow_queue_write,
   3.911 -	tdqcow_submit,
   3.912 -	tdqcow_get_fd,
   3.913 -	tdqcow_close,
   3.914 -	tdqcow_do_callbacks,
   3.915 +	.disk_type           = "tapdisk_qcow",
   3.916 +	.private_data_size   = sizeof(struct tdqcow_state),
   3.917 +	.td_open             = tdqcow_open,
   3.918 +	.td_queue_read       = tdqcow_queue_read,
   3.919 +	.td_queue_write      = tdqcow_queue_write,
   3.920 +	.td_submit           = tdqcow_submit,
   3.921 +	.td_has_parent       = tdqcow_has_parent,
   3.922 +	.td_get_parent       = tdqcow_get_parent,
   3.923 +	.td_close            = tdqcow_close,
   3.924 +	.td_do_callbacks     = tdqcow_do_callbacks,
   3.925  };
   3.926 -

     4.1 --- a/tools/blktap/drivers/block-ram.c	Fri Feb 16 16:34:28 2007 +0000
     4.2 +++ b/tools/blktap/drivers/block-ram.c	Fri Feb 16 20:31:27 2007 -0800
     4.3 @@ -123,14 +123,25 @@ static int get_image_info(struct td_stat
     4.4  	return 0;
     4.5  }
     4.6  
     4.7 +static inline void init_fds(struct disk_driver *dd)
     4.8 +{
     4.9 +        int i;
    4.10 +	struct tdram_state *prv = (struct tdram_state *)dd->private;
    4.11 +
    4.12 +        for(i =0 ; i < MAX_IOFD; i++)
    4.13 +		dd->io_fd[i] = 0;
    4.14 +
    4.15 +        dd->io_fd[0] = prv->poll_pipe[0];
    4.16 +}
    4.17 +
    4.18  /* Open the disk file and initialize ram state. */
    4.19 -int tdram_open (struct td_state *s, const char *name)
    4.20 +int tdram_open (struct disk_driver *dd, const char *name)
    4.21  {
    4.22 +	char *p;
    4.23 +	uint64_t size;
    4.24  	int i, fd, ret = 0, count = 0;
    4.25 -	struct tdram_state *prv = (struct tdram_state *)s->private;
    4.26 -	uint64_t size;
    4.27 -	char *p;
    4.28 -	s->private = prv;
    4.29 +	struct td_state    *s     = dd->td_state;
    4.30 +	struct tdram_state *prv   = (struct tdram_state *)dd->private;
    4.31  
    4.32  	connections++;
    4.33  	
    4.34 @@ -209,88 +220,80 @@ int tdram_open (struct td_state *s, cons
    4.35  		ret = 0;
    4.36  	} 
    4.37  
    4.38 +	init_fds(dd);
    4.39  done:
    4.40  	return ret;
    4.41  }
    4.42  
    4.43 - int tdram_queue_read(struct td_state *s, uint64_t sector,
    4.44 -			       int nb_sectors, char *buf, td_callback_t cb,
    4.45 -			       int id, void *private)
    4.46 + int tdram_queue_read(struct disk_driver *dd, uint64_t sector,
    4.47 +		      int nb_sectors, char *buf, td_callback_t cb,
    4.48 +		      int id, void *private)
    4.49  {
    4.50 -	struct tdram_state *prv = (struct tdram_state *)s->private;
    4.51 +	struct td_state    *s   = dd->td_state;
    4.52 +	struct tdram_state *prv = (struct tdram_state *)dd->private;
    4.53  	int      size    = nb_sectors * s->sector_size;
    4.54  	uint64_t offset  = sector * (uint64_t)s->sector_size;
    4.55 -	int ret;
    4.56  
    4.57  	memcpy(buf, img + offset, size);
    4.58 -	ret = size;
    4.59  
    4.60 -	cb(s, (ret < 0) ? ret: 0, id, private);
    4.61 -
    4.62 -	return ret;
    4.63 +	return cb(dd, 0, sector, nb_sectors, id, private);
    4.64  }
    4.65  
    4.66 - int tdram_queue_write(struct td_state *s, uint64_t sector,
    4.67 -			       int nb_sectors, char *buf, td_callback_t cb,
    4.68 -			       int id, void *private)
    4.69 +int tdram_queue_write(struct disk_driver *dd, uint64_t sector,
    4.70 +		      int nb_sectors, char *buf, td_callback_t cb,
    4.71 +		      int id, void *private)
    4.72  {
    4.73 -	struct tdram_state *prv = (struct tdram_state *)s->private;
    4.74 +	struct td_state    *s   = dd->td_state;
    4.75 +	struct tdram_state *prv = (struct tdram_state *)dd->private;
    4.76  	int      size    = nb_sectors * s->sector_size;
    4.77  	uint64_t offset  = sector * (uint64_t)s->sector_size;
    4.78 -	int ret;
    4.79  	
    4.80 -	/*We assume that write access is controlled at a higher level for multiple disks*/
    4.81 +	/* We assume that write access is controlled
    4.82 +	 * at a higher level for multiple disks */
    4.83  	memcpy(img + offset, buf, size);
    4.84 -	ret = size;
    4.85  
    4.86 -	cb(s, (ret < 0) ? ret : 0, id, private);
    4.87 -
    4.88 -	return ret;
    4.89 +	return cb(dd, 0, sector, nb_sectors, id, private);
    4.90  }
    4.91   		
    4.92 -int tdram_submit(struct td_state *s)
    4.93 +int tdram_submit(struct disk_driver *dd)
    4.94  {
    4.95  	return 0;	
    4.96  }
    4.97  
    4.98 -
    4.99 -int *tdram_get_fd(struct td_state *s)
   4.100 +int tdram_close(struct disk_driver *dd)
   4.101  {
   4.102 -	struct tdram_state *prv = (struct tdram_state *)s->private;
   4.103 -        int *fds, i;
   4.104 -
   4.105 -        fds = malloc(sizeof(int) * MAX_IOFD);
   4.106 -        /*initialise the FD array*/
   4.107 -        for(i=0;i<MAX_IOFD;i++) fds[i] = 0;
   4.108 -
   4.109 -        fds[0] = prv->poll_pipe[0];
   4.110 -        return fds;	
   4.111 -}
   4.112 -
   4.113 -int tdram_close(struct td_state *s)
   4.114 -{
   4.115 -	struct tdram_state *prv = (struct tdram_state *)s->private;
   4.116 +	struct tdram_state *prv = (struct tdram_state *)dd->private;
   4.117  	
   4.118  	connections--;
   4.119  	
   4.120  	return 0;
   4.121  }
   4.122  
   4.123 -int tdram_do_callbacks(struct td_state *s, int sid)
   4.124 +int tdram_do_callbacks(struct disk_driver *dd, int sid)
   4.125  {
   4.126  	/* always ask for a kick */
   4.127  	return 1;
   4.128  }
   4.129  
   4.130 +int tdram_has_parent(struct disk_driver *dd)
   4.131 +{
   4.132 +	return 0;
   4.133 +}
   4.134 +
   4.135 +int tdram_get_parent(struct disk_driver *dd, struct disk_driver *parent)
   4.136 +{
   4.137 +	return -EINVAL;
   4.138 +}
   4.139 +
   4.140  struct tap_disk tapdisk_ram = {
   4.141 -	"tapdisk_ram",
   4.142 -	sizeof(struct tdram_state),
   4.143 -	tdram_open,
   4.144 -	tdram_queue_read,
   4.145 -	tdram_queue_write,
   4.146 -	tdram_submit,
   4.147 -	tdram_get_fd,
   4.148 -	tdram_close,
   4.149 -	tdram_do_callbacks,
   4.150 +	.disk_type          = "tapdisk_ram",
   4.151 +	.private_data_size  = sizeof(struct tdram_state),
   4.152 +	.td_open            = tdram_open,
   4.153 +	.td_queue_read      = tdram_queue_read,
   4.154 +	.td_queue_write     = tdram_queue_write,
   4.155 +	.td_submit          = tdram_submit,
   4.156 +	.td_has_parent      = tdram_has_parent,
   4.157 +	.td_get_parent      = tdram_get_parent,
   4.158 +	.td_close           = tdram_close,
   4.159 +	.td_do_callbacks    = tdram_do_callbacks,
   4.160  };
   4.161 -

     5.1 --- a/tools/blktap/drivers/block-sync.c	Fri Feb 16 16:34:28 2007 +0000
     5.2 +++ b/tools/blktap/drivers/block-sync.c	Fri Feb 16 20:31:27 2007 -0800
     5.3 @@ -106,12 +106,23 @@ static int get_image_info(struct td_stat
     5.4  	return 0;
     5.5  }
     5.6  
     5.7 +static inline void init_fds(struct disk_driver *dd)
     5.8 +{
     5.9 +	int i;
    5.10 +	struct tdsync_state *prv = (struct tdsync_state *)dd->private;
    5.11 +	
    5.12 +	for(i = 0; i < MAX_IOFD; i++)
    5.13 +		dd->io_fd[i] = 0;
    5.14 +
    5.15 +	dd->io_fd[0] = prv->poll_pipe[0];
    5.16 +}
    5.17 +
    5.18  /* Open the disk file and initialize aio state. */
    5.19 -int tdsync_open (struct td_state *s, const char *name)
    5.20 +int tdsync_open (struct disk_driver *dd, const char *name)
    5.21  {
    5.22  	int i, fd, ret = 0;
    5.23 -	struct tdsync_state *prv = (struct tdsync_state *)s->private;
    5.24 -	s->private = prv;
    5.25 +	struct td_state     *s   = dd->td_state;
    5.26 +	struct tdsync_state *prv = (struct tdsync_state *)dd->private;
    5.27  	
    5.28  	/* set up a pipe so that we can hand back a poll fd that won't fire.*/
    5.29  	ret = pipe(prv->poll_pipe);
    5.30 @@ -138,16 +149,18 @@ int tdsync_open (struct td_state *s, con
    5.31  
    5.32          prv->fd = fd;
    5.33  
    5.34 +	init_fds(dd);
    5.35  	ret = get_image_info(s, fd);
    5.36  done:
    5.37  	return ret;	
    5.38  }
    5.39  
    5.40 - int tdsync_queue_read(struct td_state *s, uint64_t sector,
    5.41 + int tdsync_queue_read(struct disk_driver *dd, uint64_t sector,
    5.42  			       int nb_sectors, char *buf, td_callback_t cb,
    5.43  			       int id, void *private)
    5.44  {
    5.45 -	struct tdsync_state *prv = (struct tdsync_state *)s->private;
    5.46 +	struct td_state     *s   = dd->td_state;
    5.47 +	struct tdsync_state *prv = (struct tdsync_state *)dd->private;
    5.48  	int      size    = nb_sectors * s->sector_size;
    5.49  	uint64_t offset  = sector * (uint64_t)s->sector_size;
    5.50  	int ret;
    5.51 @@ -162,16 +175,15 @@ done:
    5.52  		} 
    5.53  	} else ret = 0 - errno;
    5.54  		
    5.55 -	cb(s, (ret < 0) ? ret: 0, id, private);
    5.56 -	
    5.57 -	return 1;
    5.58 +	return cb(dd, (ret < 0) ? ret: 0, sector, nb_sectors, id, private);
    5.59  }
    5.60  
    5.61 - int tdsync_queue_write(struct td_state *s, uint64_t sector,
    5.62 + int tdsync_queue_write(struct disk_driver *dd, uint64_t sector,
    5.63  			       int nb_sectors, char *buf, td_callback_t cb,
    5.64  			       int id, void *private)
    5.65  {
    5.66 -	struct tdsync_state *prv = (struct tdsync_state *)s->private;
    5.67 +	struct td_state     *s   = dd->td_state;
    5.68 +	struct tdsync_state *prv = (struct tdsync_state *)dd->private;
    5.69  	int      size    = nb_sectors * s->sector_size;
    5.70  	uint64_t offset  = sector * (uint64_t)s->sector_size;
    5.71  	int ret = 0;
    5.72 @@ -186,34 +198,17 @@ done:
    5.73  		}
    5.74  	} else ret = 0 - errno;
    5.75  		
    5.76 -	cb(s, (ret < 0) ? ret : 0, id, private);
    5.77 -	
    5.78 -	return 1;
    5.79 +	return cb(dd, (ret < 0) ? ret : 0, sector, nb_sectors, id, private);
    5.80  }
    5.81   		
    5.82 -int tdsync_submit(struct td_state *s)
    5.83 +int tdsync_submit(struct disk_driver *dd)
    5.84  {
    5.85  	return 0;	
    5.86  }
    5.87  
    5.88 -
    5.89 -int *tdsync_get_fd(struct td_state *s)
    5.90 +int tdsync_close(struct disk_driver *dd)
    5.91  {
    5.92 -	struct tdsync_state *prv = (struct tdsync_state *)s->private;
    5.93 -	
    5.94 -	int *fds, i;
    5.95 -
    5.96 -	fds = malloc(sizeof(int) * MAX_IOFD);
    5.97 -	/*initialise the FD array*/
    5.98 -	for(i=0;i<MAX_IOFD;i++) fds[i] = 0;
    5.99 -
   5.100 -	fds[0] = prv->poll_pipe[0];
   5.101 -	return fds;
   5.102 -}
   5.103 -
   5.104 -int tdsync_close(struct td_state *s)
   5.105 -{
   5.106 -	struct tdsync_state *prv = (struct tdsync_state *)s->private;
   5.107 +	struct tdsync_state *prv = (struct tdsync_state *)dd->private;
   5.108  	
   5.109  	close(prv->fd);
   5.110  	close(prv->poll_pipe[0]);
   5.111 @@ -222,21 +217,31 @@ int tdsync_close(struct td_state *s)
   5.112  	return 0;
   5.113  }
   5.114  
   5.115 -int tdsync_do_callbacks(struct td_state *s, int sid)
   5.116 +int tdsync_do_callbacks(struct disk_driver *dd, int sid)
   5.117  {
   5.118  	/* always ask for a kick */
   5.119  	return 1;
   5.120  }
   5.121  
   5.122 +int tdsync_has_parent(struct disk_driver *dd)
   5.123 +{
   5.124 +	return 0;
   5.125 +}
   5.126 +
   5.127 +int tdsync_get_parent(struct disk_driver *dd, struct disk_driver *parent)
   5.128 +{
   5.129 +	return -EINVAL;
   5.130 +}
   5.131 +
   5.132  struct tap_disk tapdisk_sync = {
   5.133 -	"tapdisk_sync",
   5.134 -	sizeof(struct tdsync_state),
   5.135 -	tdsync_open,
   5.136 -	tdsync_queue_read,
   5.137 -	tdsync_queue_write,
   5.138 -	tdsync_submit,
   5.139 -	tdsync_get_fd,
   5.140 -	tdsync_close,
   5.141 -	tdsync_do_callbacks,
   5.142 +	.disk_type           = "tapdisk_sync",
   5.143 +	.private_data_size   = sizeof(struct tdsync_state),
   5.144 +	.td_open             = tdsync_open,
   5.145 +	.td_queue_read       = tdsync_queue_read,
   5.146 +	.td_queue_write      = tdsync_queue_write,
   5.147 +	.td_submit           = tdsync_submit,
   5.148 +	.td_has_parent       = tdsync_has_parent,
   5.149 +	.td_get_parent       = tdsync_get_parent,
   5.150 +	.td_close            = tdsync_close,
   5.151 +	.td_do_callbacks     = tdsync_do_callbacks,
   5.152  };
   5.153 -

     6.1 --- a/tools/blktap/drivers/block-vmdk.c	Fri Feb 16 16:34:28 2007 +0000
     6.2 +++ b/tools/blktap/drivers/block-vmdk.c	Fri Feb 16 20:31:27 2007 -0800
     6.3 @@ -107,14 +107,25 @@ struct tdvmdk_state {
     6.4      	unsigned int cluster_sectors;
     6.5  };
     6.6  
     6.7 +static inline void init_fds(struct disk_driver *dd)
     6.8 +{
     6.9 +        int i;
    6.10 +	struct tdvmdk_state *prv = (struct tdvmdk_state *)dd->private;
    6.11 +
    6.12 +        for (i = 0; i < MAX_IOFD; i++)
    6.13 +		dd->io_fd[i] = 0;
    6.14 +
    6.15 +        dd->io_fd[0] = prv->poll_pipe[0];
    6.16 +}
    6.17  
    6.18  /* Open the disk file and initialize aio state. */
    6.19 -static int tdvmdk_open (struct td_state *s, const char *name)
    6.20 +static int tdvmdk_open (struct disk_driver *dd, const char *name)
    6.21  {
    6.22  	int ret, fd;
    6.23      	int l1_size, i;
    6.24      	uint32_t magic;
    6.25 -	struct tdvmdk_state *prv = (struct tdvmdk_state *)s->private;
    6.26 +	struct td_state     *s   = dd->td_state;
    6.27 +	struct tdvmdk_state *prv = (struct tdvmdk_state *)dd->private;
    6.28  
    6.29  	/* set up a pipe so that we can hand back a poll fd that won't fire.*/
    6.30  	ret = pipe(prv->poll_pipe);
    6.31 @@ -206,6 +217,7 @@ static int tdvmdk_open (struct td_state 
    6.32      	if (!prv->l2_cache)
    6.33          	goto fail;
    6.34      	prv->fd = fd;
    6.35 +	init_fds(dd);
    6.36  	DPRINTF("VMDK File opened successfully\n");
    6.37      	return 0;
    6.38  	
    6.39 @@ -218,10 +230,9 @@ fail:
    6.40  	return -1;
    6.41  }
    6.42  
    6.43 -static uint64_t get_cluster_offset(struct td_state *s, 
    6.44 +static uint64_t get_cluster_offset(struct tdvmdk_state *prv, 
    6.45                                     uint64_t offset, int allocate)
    6.46  {
    6.47 -	struct tdvmdk_state *prv = (struct tdvmdk_state *)s->private;
    6.48      	unsigned int l1_index, l2_offset, l2_index;
    6.49      	int min_index, i, j;
    6.50      	uint32_t min_count, *l2_table, tmp;
    6.51 @@ -291,16 +302,17 @@ static uint64_t get_cluster_offset(struc
    6.52      	return cluster_offset;
    6.53  }
    6.54  
    6.55 -static int tdvmdk_queue_read(struct td_state *s, uint64_t sector,
    6.56 +static int tdvmdk_queue_read(struct disk_driver *dd, uint64_t sector,
    6.57  			       int nb_sectors, char *buf, td_callback_t cb,
    6.58  			       int id, void *private)
    6.59  {
    6.60 -	struct tdvmdk_state *prv = (struct tdvmdk_state *)s->private;
    6.61 +	struct tdvmdk_state *prv = (struct tdvmdk_state *)dd->private;
    6.62      	int index_in_cluster, n;
    6.63      	uint64_t cluster_offset;
    6.64      	int ret = 0;
    6.65 +
    6.66      	while (nb_sectors > 0) {
    6.67 -        	cluster_offset = get_cluster_offset(s, sector << 9, 0);
    6.68 +        	cluster_offset = get_cluster_offset(prv, sector << 9, 0);
    6.69          	index_in_cluster = sector % prv->cluster_sectors;
    6.70          	n = prv->cluster_sectors - index_in_cluster;
    6.71          	if (n > nb_sectors)
    6.72 @@ -321,27 +333,24 @@ static int tdvmdk_queue_read(struct td_s
    6.73          	buf += n * 512;
    6.74      	}
    6.75  done:
    6.76 -	cb(s, ret == -1 ? -1 : 0, id, private);
    6.77 -	
    6.78 -	return 1;
    6.79 +	return cb(dd, ret == -1 ? -1 : 0, sector, nb_sectors, id, private);
    6.80  }
    6.81  
    6.82 -static  int tdvmdk_queue_write(struct td_state *s, uint64_t sector,
    6.83 +static  int tdvmdk_queue_write(struct disk_driver *dd, uint64_t sector,
    6.84  			       int nb_sectors, char *buf, td_callback_t cb,
    6.85  			       int id, void *private)
    6.86  {
    6.87 -	struct tdvmdk_state *prv = (struct tdvmdk_state *)s->private;
    6.88 +	struct tdvmdk_state *prv = (struct tdvmdk_state *)dd->private;
    6.89      	int index_in_cluster, n;
    6.90      	uint64_t cluster_offset;
    6.91      	int ret = 0;
    6.92 -    	
    6.93  
    6.94      	while (nb_sectors > 0) {
    6.95          	index_in_cluster = sector & (prv->cluster_sectors - 1);
    6.96          	n = prv->cluster_sectors - index_in_cluster;
    6.97          	if (n > nb_sectors)
    6.98              		n = nb_sectors;
    6.99 -        	cluster_offset = get_cluster_offset(s, sector << 9, 1);
   6.100 +        	cluster_offset = get_cluster_offset(prv, sector << 9, 1);
   6.101          	if (!cluster_offset) {
   6.102              		ret = -1;
   6.103              		goto done;
   6.104 @@ -358,33 +367,17 @@ static  int tdvmdk_queue_write(struct td
   6.105          	buf += n * 512;
   6.106      	}
   6.107  done:
   6.108 -	cb(s, ret == -1 ? -1 : 0, id, private);
   6.109 -	
   6.110 -	return 1;
   6.111 +	return cb(dd, ret == -1 ? -1 : 0, sector, nb_sectors, id, private);
   6.112  }
   6.113   		
   6.114 -static int tdvmdk_submit(struct td_state *s)
   6.115 +static int tdvmdk_submit(struct disk_driver *dd)
   6.116  {
   6.117  	return 0;	
   6.118  }
   6.119  
   6.120 -
   6.121 -static int *tdvmdk_get_fd(struct td_state *s)
   6.122 +static int tdvmdk_close(struct disk_driver *dd)
   6.123  {
   6.124 -	struct tdvmdk_state *prv = (struct tdvmdk_state *)s->private;
   6.125 -        int *fds, i;
   6.126 -
   6.127 -        fds = malloc(sizeof(int) * MAX_IOFD);
   6.128 -        /*initialise the FD array*/
   6.129 -        for (i=0;i<MAX_IOFD;i++) fds[i] = 0;
   6.130 -
   6.131 -        fds[0] = prv->poll_pipe[0];
   6.132 -        return fds;
   6.133 -}
   6.134 -
   6.135 -static int tdvmdk_close(struct td_state *s)
   6.136 -{
   6.137 -	struct tdvmdk_state *prv = (struct tdvmdk_state *)s->private;
   6.138 +	struct tdvmdk_state *prv = (struct tdvmdk_state *)dd->private;
   6.139  	
   6.140      	safer_free(prv->l1_table);
   6.141      	safer_free(prv->l1_backup_table);
   6.142 @@ -395,21 +388,31 @@ static int tdvmdk_close(struct td_state 
   6.143  	return 0;
   6.144  }
   6.145  
   6.146 -static int tdvmdk_do_callbacks(struct td_state *s, int sid)
   6.147 +static int tdvmdk_do_callbacks(struct disk_driver *dd, int sid)
   6.148  {
   6.149  	/* always ask for a kick */
   6.150  	return 1;
   6.151  }
   6.152  
   6.153 +static int tdvmdk_has_parent(struct disk_driver *dd)
   6.154 +{
   6.155 +	return 0;
   6.156 +}
   6.157 +
   6.158 +static int tdvmdk_get_parent(struct disk_driver *dd, struct disk_driver *parent)
   6.159 +{
   6.160 +	return -EINVAL;
   6.161 +}
   6.162 +
   6.163  struct tap_disk tapdisk_vmdk = {
   6.164 -	"tapdisk_vmdk",
   6.165 -	sizeof(struct tdvmdk_state),
   6.166 -	tdvmdk_open,
   6.167 -	tdvmdk_queue_read,
   6.168 -	tdvmdk_queue_write,
   6.169 -	tdvmdk_submit,
   6.170 -	tdvmdk_get_fd,
   6.171 -	tdvmdk_close,
   6.172 -	tdvmdk_do_callbacks,
   6.173 +	.disk_type           = "tapdisk_vmdk",
   6.174 +	.private_data_size   = sizeof(struct tdvmdk_state),
   6.175 +	.td_open             = tdvmdk_open,
   6.176 +	.td_queue_read       = tdvmdk_queue_read,
   6.177 +	.td_queue_write      = tdvmdk_queue_write,
   6.178 +	.td_submit           = tdvmdk_submit,
   6.179 +	.td_has_parent       = tdvmdk_has_parent,
   6.180 +	.td_get_parent       = tdvmdk_get_parent,
   6.181 +	.td_close            = tdvmdk_close,
   6.182 +	.td_do_callbacks     = tdvmdk_do_callbacks,
   6.183  };
   6.184 -

     7.1 --- a/tools/blktap/drivers/img2qcow.c	Fri Feb 16 16:34:28 2007 +0000
     7.2 +++ b/tools/blktap/drivers/img2qcow.c	Fri Feb 16 20:31:27 2007 -0800
     7.3 @@ -147,7 +147,8 @@ static int get_image_info(struct td_stat
     7.4  	return 0;
     7.5  }
     7.6  
     7.7 -static int send_responses(struct td_state *s, int res, int idx, void *private)
     7.8 +static int send_responses(struct disk_driver *dd, int res, uint64_t sec, 
     7.9 +			  int nr_secs, int idx, void *private)
    7.10  {
    7.11  	if (res < 0) DFPRINTF("AIO FAILURE: res [%d]!\n",res);
    7.12  	
    7.13 @@ -159,7 +160,7 @@ static int send_responses(struct td_stat
    7.14  
    7.15  int main(int argc, char *argv[])
    7.16  {
    7.17 -	struct tap_disk *drv;
    7.18 +	struct disk_driver dd;
    7.19  	struct td_state *s;
    7.20  	int ret = -1, fd, len;
    7.21  	fd_set readfds;
    7.22 @@ -195,16 +196,17 @@ int main(int argc, char *argv[])
    7.23  	} else DFPRINTF("Qcow file created: size %llu sectors\n",
    7.24  			(long long unsigned)s->size);
    7.25  	
    7.26 -	drv = &tapdisk_qcow;
    7.27 -	s->private = malloc(drv->private_data_size);
    7.28 +	dd.td_state = s;
    7.29 +	dd.drv      = &tapdisk_qcow;
    7.30 +	dd.private  = malloc(dd.drv->private_data_size);
    7.31  
    7.32          /*Open qcow file*/
    7.33 -        if (drv->td_open(s, argv[1])!=0) {
    7.34 +        if (dd.drv->td_open(&dd, argv[1])!=0) {
    7.35  		DFPRINTF("Unable to open Qcow file [%s]\n",argv[1]);
    7.36  		exit(-1);
    7.37  	}
    7.38  
    7.39 -	io_fd = drv->td_get_fd(s);
    7.40 +	io_fd = dd.io_fd;
    7.41  
    7.42  	/*Initialise the output string*/
    7.43  	memset(output,0x20,25);
    7.44 @@ -245,9 +247,9 @@ int main(int argc, char *argv[])
    7.45  				len = (len >> 9) << 9;
    7.46  			}
    7.47  
    7.48 -			ret = drv->td_queue_write(s, i >> 9,
    7.49 -						  len >> 9, buf, 
    7.50 -						  send_responses, 0, buf);
    7.51 +			ret = dd.drv->td_queue_write(&dd, i >> 9,
    7.52 +						     len >> 9, buf, 
    7.53 +						     send_responses, 0, buf);
    7.54  				
    7.55  			if (!ret) submit_events++;
    7.56  				
    7.57 @@ -261,7 +263,7 @@ int main(int argc, char *argv[])
    7.58  			debug_output(i,s->size << 9);
    7.59  			
    7.60  			if ((submit_events % 10 == 0) || complete) 
    7.61 -				drv->td_submit(s);
    7.62 +				dd.drv->td_submit(&dd);
    7.63  			timeout.tv_usec = 0;
    7.64  			
    7.65  		} else {
    7.66 @@ -275,14 +277,14 @@ int main(int argc, char *argv[])
    7.67                  ret = select(maxfds + 1, &readfds, (fd_set *) 0,
    7.68                               (fd_set *) 0, &timeout);
    7.69  			     
    7.70 -		if (ret > 0) drv->td_do_callbacks(s, 0);
    7.71 +		if (ret > 0) dd.drv->td_do_callbacks(&dd, 0);
    7.72  		if (complete && (returned_events == submit_events)) 
    7.73  			running = 0;
    7.74  	}
    7.75  	memcpy(output+prev+1,"=",1);
    7.76  	DFPRINTF("\r%s     100%%\nTRANSFER COMPLETE\n\n", output);
    7.77 -        drv->td_close(s);
    7.78 -        free(s->private);
    7.79 +        dd.drv->td_close(&dd);
    7.80 +        free(dd.private);
    7.81          free(s);
    7.82  		
    7.83  	return 0;

     8.1 --- a/tools/blktap/drivers/qcow2raw.c	Fri Feb 16 16:34:28 2007 +0000
     8.2 +++ b/tools/blktap/drivers/qcow2raw.c	Fri Feb 16 20:31:27 2007 -0800
     8.3 @@ -55,8 +55,7 @@ static int read_complete = 0, write_comp
     8.4  static int returned_read_events = 0, returned_write_events = 0;
     8.5  static int submit_events = 0;
     8.6  static uint32_t read_idx = 0, write_idx = 0;
     8.7 -struct tap_disk *drv1, *drv2;
     8.8 -struct td_state *sqcow, *saio;
     8.9 +struct disk_driver ddqcow, ddaio;
    8.10  static uint64_t prev = 0, written = 0;
    8.11  static char output[25];
    8.12  
    8.13 @@ -100,7 +99,8 @@ static inline void LOCAL_FD_SET(fd_set *
    8.14  	return;
    8.15  }
    8.16  
    8.17 -static int send_write_responses(struct td_state *s, int res, int idx, void *private)
    8.18 +static int send_write_responses(struct disk_driver *dd, int res, uint64_t sec,
    8.19 +				int nr_secs, int idx, void *private)
    8.20  {
    8.21  	if (res < 0) {
    8.22  		DFPRINTF("AIO FAILURE: res [%d]!\n",res);
    8.23 @@ -112,12 +112,13 @@ static int send_write_responses(struct t
    8.24  	if (complete && (returned_write_events == submit_events)) 
    8.25  		write_complete = 1;
    8.26  
    8.27 -	debug_output(written, s->size << 9);
    8.28 +	debug_output(written, dd->td_state->size << 9);
    8.29  	free(private);
    8.30  	return 0;
    8.31  }
    8.32  
    8.33 -static int send_read_responses(struct td_state *s, int res, int idx, void *private)
    8.34 +static int send_read_responses(struct disk_driver *dd, int res, uint64_t sec,
    8.35 +			       int nr_secs, int idx, void *private)
    8.36  {
    8.37  	int ret;
    8.38  
    8.39 @@ -128,8 +129,8 @@ static int send_read_responses(struct td
    8.40  	if (complete && (returned_read_events == submit_events)) 
    8.41  		read_complete = 1;
    8.42  	
    8.43 -	ret = drv2->td_queue_write(saio, idx, BLOCK_PROCESSSZ>>9, private, 
    8.44 -				   send_write_responses, idx, private);
    8.45 +	ret = ddaio.drv->td_queue_write(&ddaio, idx, BLOCK_PROCESSSZ>>9, private, 
    8.46 +					send_write_responses, idx, private);
    8.47  	if (ret != 0) {
    8.48  		DFPRINTF("ERROR in submitting queue write!\n");
    8.49  		return 0;
    8.50 @@ -137,7 +138,7 @@ static int send_read_responses(struct td
    8.51  
    8.52  	if ( (complete && returned_read_events == submit_events) || 
    8.53  	     (returned_read_events % 10 == 0) ) {
    8.54 -		drv2->td_submit(saio);
    8.55 +		ddaio.drv->td_submit(&ddaio);
    8.56  	}
    8.57  
    8.58  	return 0;
    8.59 @@ -161,20 +162,20 @@ int main(int argc, char *argv[])
    8.60  		exit(-1);
    8.61  	}
    8.62  
    8.63 -	sqcow = malloc(sizeof(struct td_state));
    8.64 -	saio  = malloc(sizeof(struct td_state));
    8.65 +	ddqcow.td_state = malloc(sizeof(struct td_state));
    8.66 +	ddaio.td_state  = malloc(sizeof(struct td_state));
    8.67  	
    8.68  	/*Open qcow source file*/	
    8.69 -	drv1 = &tapdisk_qcow;
    8.70 -	sqcow->private = malloc(drv1->private_data_size);
    8.71 +	ddqcow.drv = &tapdisk_qcow;
    8.72 +	ddqcow.private = malloc(ddqcow.drv->private_data_size);
    8.73  
    8.74 -        if (drv1->td_open(sqcow, argv[2])!=0) {
    8.75 +        if (ddqcow.drv->td_open(&ddqcow, argv[2])!=0) {
    8.76  		DFPRINTF("Unable to open Qcow file [%s]\n",argv[2]);
    8.77  		exit(-1);
    8.78  	} else DFPRINTF("QCOW file opened, size %llu\n",
    8.79 -		      (long long unsigned)sqcow->size);
    8.80 +		      (long long unsigned)ddqcow.td_state->size);
    8.81  
    8.82 -	qcowio_fd = drv1->td_get_fd(sqcow);
    8.83 +	qcowio_fd = ddqcow.io_fd;
    8.84  
    8.85          /*Setup aio destination file*/
    8.86  	ret = stat(argv[1],&finfo);
    8.87 @@ -191,12 +192,12 @@ int main(int argc, char *argv[])
    8.88  				       argv[1], 0 - errno);
    8.89  				exit(-1);
    8.90  			}
    8.91 -			if (ftruncate(fd, (off_t)sqcow->size<<9) < 0) {
    8.92 +			if (ftruncate(fd, (off_t)ddqcow.td_state->size<<9) < 0) {
    8.93  				DFPRINTF("Unable to create file "
    8.94  					"[%s] of size %llu (errno %d). "
    8.95  					 "Exiting...\n",
    8.96  					argv[1], 
    8.97 -					(long long unsigned)sqcow->size<<9, 
    8.98 +					(long long unsigned)ddqcow.td_state->size<<9, 
    8.99  					0 - errno);
   8.100  				close(fd);
   8.101  				exit(-1);
   8.102 @@ -238,43 +239,43 @@ int main(int argc, char *argv[])
   8.103  				close(fd);
   8.104  				exit(-1);
   8.105  			}
   8.106 -			if (size < sqcow->size<<9) {
   8.107 +			if (size < ddqcow.td_state->size<<9) {
   8.108  				DFPRINTF("ERROR: Not enough space on device "
   8.109  					"%s (%lu bytes available, %llu bytes required\n",
   8.110  					argv[1], size, 
   8.111 -					(long long unsigned)sqcow->size<<9);
   8.112 +					(long long unsigned)ddqcow.td_state->size<<9);
   8.113  				close(fd);
   8.114  				exit(-1);				
   8.115  			}
   8.116  		} else {
   8.117 -			if (ftruncate(fd, (off_t)sqcow->size<<9) < 0) {
   8.118 +			if (ftruncate(fd, (off_t)ddqcow.td_state->size<<9) < 0) {
   8.119  				DFPRINTF("Unable to create file "
   8.120  					"[%s] of size %llu (errno %d). "
   8.121  					 "Exiting...\n",
   8.122  					argv[1], 
   8.123 -					(long long unsigned)sqcow->size<<9, 
   8.124 +					(long long unsigned)ddqcow.td_state->size<<9, 
   8.125  					 0 - errno);
   8.126  				close(fd);
   8.127  				exit(-1);
   8.128  			} else DFPRINTF("File [%s] truncated to length %llu "
   8.129  					"(%llu)\n", 
   8.130  				       argv[1], 
   8.131 -				       (long long unsigned)sqcow->size<<9, 
   8.132 -				       (long long unsigned)sqcow->size);
   8.133 +				       (long long unsigned)ddqcow.td_state->size<<9, 
   8.134 +				       (long long unsigned)ddqcow.td_state->size);
   8.135  		}
   8.136  		close(fd);
   8.137  	}
   8.138  
   8.139  	/*Open aio destination file*/	
   8.140 -	drv2 = &tapdisk_aio;
   8.141 -	saio->private = malloc(drv2->private_data_size);
   8.142 +	ddaio.drv = &tapdisk_aio;
   8.143 +	ddaio.private = malloc(ddaio.drv->private_data_size);
   8.144  
   8.145 -        if (drv2->td_open(saio, argv[1])!=0) {
   8.146 +        if (ddaio.drv->td_open(&ddaio, argv[1])!=0) {
   8.147  		DFPRINTF("Unable to open Qcow file [%s]\n", argv[1]);
   8.148  		exit(-1);
   8.149  	}
   8.150  
   8.151 -	aio_fd = drv2->td_get_fd(saio);
   8.152 +	aio_fd = ddaio.io_fd;
   8.153  
   8.154  	/*Initialise the output string*/
   8.155  	memset(output,0x20,25);
   8.156 @@ -298,9 +299,9 @@ int main(int argc, char *argv[])
   8.157  			}
   8.158  		
   8.159  			/*Attempt to read 4k sized blocks*/
   8.160 -			ret = drv1->td_queue_read(sqcow, i>>9,
   8.161 -						  BLOCK_PROCESSSZ>>9, buf, 
   8.162 -						  send_read_responses, i>>9, buf);
   8.163 +			ret = ddqcow.drv->td_queue_read(&ddqcow, i>>9,
   8.164 +							BLOCK_PROCESSSZ>>9, buf, 
   8.165 +							send_read_responses, i>>9, buf);
   8.166  
   8.167  			if (ret < 0) {
   8.168  				DFPRINTF("UNABLE TO READ block [%llu]\n",
   8.169 @@ -311,12 +312,12 @@ int main(int argc, char *argv[])
   8.170  				submit_events++;
   8.171  			}
   8.172  
   8.173 -			if (i >= sqcow->size<<9) {
   8.174 +			if (i >= ddqcow.td_state->size<<9) {
   8.175  				complete = 1;
   8.176  			}
   8.177  			
   8.178  			if ((submit_events % 10 == 0) || complete) 
   8.179 -				drv1->td_submit(sqcow);
   8.180 +				ddqcow.drv->td_submit(&ddqcow);
   8.181  			timeout.tv_usec = 0;
   8.182  			
   8.183  		} else {
   8.184 @@ -332,9 +333,9 @@ int main(int argc, char *argv[])
   8.185  			     
   8.186  		if (ret > 0) {
   8.187  			if (FD_ISSET(qcowio_fd[0], &readfds)) 
   8.188 -				drv1->td_do_callbacks(sqcow, 0);
   8.189 +				ddqcow.drv->td_do_callbacks(&ddqcow, 0);
   8.190  			if (FD_ISSET(aio_fd[0], &readfds)) 
   8.191 -				drv2->td_do_callbacks(saio, 0);
   8.192 +				ddaio.drv->td_do_callbacks(&ddaio, 0);
   8.193  		}
   8.194  		if (complete && (returned_write_events == submit_events)) 
   8.195  			running = 0;

     9.1 --- a/tools/blktap/drivers/tapdisk.c	Fri Feb 16 16:34:28 2007 +0000
     9.2 +++ b/tools/blktap/drivers/tapdisk.c	Fri Feb 16 20:31:27 2007 -0800
     9.3 @@ -48,6 +48,12 @@ static pid_t process;
     9.4  int connected_disks = 0;
     9.5  fd_list_entry_t *fd_start = NULL;
     9.6  
     9.7 +int do_cow_read(struct disk_driver *dd, blkif_request_t *req, 
     9.8 +		int sidx, uint64_t sector, int nr_secs);
     9.9 +
    9.10 +#define td_for_each_disk(tds, drv) \
    9.11 +        for (drv = tds->disks; drv != NULL; drv = drv->next)
    9.12 +
    9.13  void usage(void) 
    9.14  {
    9.15  	fprintf(stderr, "blktap-utils: v1.0.0\n");
    9.16 @@ -78,10 +84,17 @@ void daemonize(void)
    9.17  static void unmap_disk(struct td_state *s)
    9.18  {
    9.19  	tapdev_info_t *info = s->ring_info;
    9.20 -	struct tap_disk *drv = s->drv;
    9.21 +	struct disk_driver *dd, *tmp;
    9.22  	fd_list_entry_t *entry;
    9.23  
    9.24 -	drv->td_close(s);
    9.25 +	dd = s->disks;
    9.26 +	while (dd) {
    9.27 +		tmp = dd->next;
    9.28 +		dd->drv->td_close(dd);
    9.29 +		free(dd->private);
    9.30 +		free(dd);
    9.31 +		dd = tmp;
    9.32 +	}
    9.33  
    9.34  	if (info != NULL && info->mem > 0)
    9.35  	        munmap(info->mem, getpagesize() * BLKTAP_MMAP_REGION_SIZE);
    9.36 @@ -96,7 +109,6 @@ static void unmap_disk(struct td_state *
    9.37  	free(s->fd_entry);
    9.38  	free(s->blkif);
    9.39  	free(s->ring_info);
    9.40 -        free(s->private);
    9.41  	free(s);
    9.42  
    9.43  	return;
    9.44 @@ -113,16 +125,19 @@ void sig_handler(int sig)
    9.45  static inline int LOCAL_FD_SET(fd_set *readfds)
    9.46  {
    9.47  	fd_list_entry_t *ptr;
    9.48 +	struct disk_driver *dd;
    9.49  
    9.50  	ptr = fd_start;
    9.51  	while (ptr != NULL) {
    9.52  		if (ptr->tap_fd) {
    9.53  			FD_SET(ptr->tap_fd, readfds);
    9.54 -			if (ptr->io_fd[READ]) 
    9.55 -				FD_SET(ptr->io_fd[READ], readfds);
    9.56 -			maxfds = (ptr->io_fd[READ] > maxfds ? 
    9.57 -					ptr->io_fd[READ]: maxfds);
    9.58 -			maxfds = (ptr->tap_fd > maxfds ? ptr->tap_fd: maxfds);
    9.59 +			td_for_each_disk(ptr->s, dd) {
    9.60 +				if (dd->io_fd[READ]) 
    9.61 +					FD_SET(dd->io_fd[READ], readfds);
    9.62 +				maxfds = (dd->io_fd[READ] > maxfds ? 
    9.63 +					  dd->io_fd[READ] : maxfds);
    9.64 +			}
    9.65 +			maxfds = (ptr->tap_fd > maxfds ? ptr->tap_fd : maxfds);
    9.66  		}
    9.67  		ptr = ptr->next;
    9.68  	}
    9.69 @@ -130,8 +145,7 @@ static inline int LOCAL_FD_SET(fd_set *r
    9.70  	return 0;
    9.71  }
    9.72  
    9.73 -static inline fd_list_entry_t *add_fd_entry(
    9.74 -	int tap_fd, int io_fd[MAX_IOFD], struct td_state *s)
    9.75 +static inline fd_list_entry_t *add_fd_entry(int tap_fd, struct td_state *s)
    9.76  {
    9.77  	fd_list_entry_t **pprev, *entry;
    9.78  	int i;
    9.79 @@ -139,12 +153,10 @@ static inline fd_list_entry_t *add_fd_en
    9.80  	DPRINTF("Adding fd_list_entry\n");
    9.81  
    9.82  	/*Add to linked list*/
    9.83 -	s->fd_entry = entry = malloc(sizeof(fd_list_entry_t));
    9.84 +	s->fd_entry   = entry = malloc(sizeof(fd_list_entry_t));
    9.85  	entry->tap_fd = tap_fd;
    9.86 -	for (i = 0; i < MAX_IOFD; i++)
    9.87 -		entry->io_fd[i] = io_fd[i];
    9.88 -	entry->s = s;
    9.89 -	entry->next = NULL;
    9.90 +	entry->s      = s;
    9.91 +	entry->next   = NULL;
    9.92  
    9.93  	pprev = &fd_start;
    9.94  	while (*pprev != NULL)
    9.95 @@ -171,7 +183,7 @@ static inline struct td_state *get_state
    9.96  static struct tap_disk *get_driver(int drivertype)
    9.97  {
    9.98  	/* blktapctrl has passed us the driver type */
    9.99 -	
   9.100 +
   9.101  	return dtypes[drivertype]->drv;
   9.102  }
   9.103  
   9.104 @@ -183,14 +195,36 @@ static struct td_state *state_init(void)
   9.105  
   9.106  	s = malloc(sizeof(struct td_state));
   9.107  	blkif = s->blkif = malloc(sizeof(blkif_t));
   9.108 -	s->ring_info = malloc(sizeof(tapdev_info_t));
   9.109 +	s->ring_info = calloc(1, sizeof(tapdev_info_t));
   9.110  
   9.111 -	for (i = 0; i < MAX_REQUESTS; i++)
   9.112 -		blkif->pending_list[i].count = 0;
   9.113 +	for (i = 0; i < MAX_REQUESTS; i++) {
   9.114 +		blkif->pending_list[i].secs_pending = 0;
   9.115 +		blkif->pending_list[i].submitting = 0;
   9.116 +	}
   9.117  
   9.118  	return s;
   9.119  }
   9.120  
   9.121 +static struct disk_driver *disk_init(struct td_state *s, struct tap_disk *drv)
   9.122 +{
   9.123 +	struct disk_driver *dd;
   9.124 +
   9.125 +	dd = calloc(1, sizeof(struct disk_driver));
   9.126 +	if (!dd)
   9.127 +		return NULL;
   9.128 +	
   9.129 +	dd->private = malloc(drv->private_data_size);
   9.130 +	if (!dd->private) {
   9.131 +		free(dd);
   9.132 +		return NULL;
   9.133 +	}
   9.134 +
   9.135 +	dd->drv      = drv;
   9.136 +	dd->td_state = s;
   9.137 +
   9.138 +	return dd;
   9.139 +}
   9.140 +
   9.141  static int map_new_dev(struct td_state *s, int minor)
   9.142  {
   9.143  	int tap_fd;
   9.144 @@ -246,6 +280,51 @@ static int map_new_dev(struct td_state *
   9.145  	return -1;
   9.146  }
   9.147  
   9.148 +static int open_disk(struct td_state *s, struct disk_driver *dd, char *path)
   9.149 +{
   9.150 +	int err;
   9.151 +	struct disk_driver *d = dd;
   9.152 +
   9.153 +	err = dd->drv->td_open(dd, path);
   9.154 +	if (err)
   9.155 +		return err;
   9.156 +
   9.157 +	/* load backing files as necessary */
   9.158 +	while (d->drv->td_has_parent(d)) {
   9.159 +		struct disk_driver *new;
   9.160 +		
   9.161 +		new = calloc(1, sizeof(struct disk_driver));
   9.162 +		if (!new)
   9.163 +			goto fail;
   9.164 +		new->drv      = d->drv;
   9.165 +		new->td_state = s;
   9.166 +		new->private  = malloc(new->drv->private_data_size);
   9.167 +		if (!new->private) {
   9.168 +			free(new);
   9.169 +			goto fail;
   9.170 +		}
   9.171 +		
   9.172 +		err = d->drv->td_get_parent(d, new);
   9.173 +		if (err)
   9.174 +			goto fail;
   9.175 +
   9.176 +		d = d->next = new;
   9.177 +	}
   9.178 +
   9.179 +	return 0;
   9.180 +
   9.181 + fail:
   9.182 +	DPRINTF("failed opening disk\n");
   9.183 +	while (dd) {
   9.184 +		d = dd->next;
   9.185 +		dd->drv->td_close(dd);
   9.186 +		free(dd->private);
   9.187 +		free(dd);
   9.188 +		dd = d;
   9.189 +	}
   9.190 +	return err;
   9.191 +}
   9.192 +
   9.193  static int read_msg(char *buf)
   9.194  {
   9.195  	int length, len, msglen, tap_fd, *io_fd;
   9.196 @@ -255,6 +334,7 @@ static int read_msg(char *buf)
   9.197  	msg_newdev_t *msg_dev;
   9.198  	msg_pid_t *msg_pid;
   9.199  	struct tap_disk *drv;
   9.200 +	struct disk_driver *dd;
   9.201  	int ret = -1;
   9.202  	struct td_state *s = NULL;
   9.203  	fd_list_entry_t *entry;
   9.204 @@ -289,20 +369,20 @@ static int read_msg(char *buf)
   9.205  			if (s == NULL)
   9.206  				goto params_done;
   9.207  
   9.208 -			s->drv = drv;
   9.209 -			s->private = malloc(drv->private_data_size);
   9.210 -			if (s->private == NULL) {
   9.211 +			s->disks = dd = disk_init(s, drv);
   9.212 +			if (!dd) {
   9.213  				free(s);
   9.214  				goto params_done;
   9.215  			}
   9.216  
   9.217  			/*Open file*/
   9.218 -			ret = drv->td_open(s, path);
   9.219 -			io_fd = drv->td_get_fd(s);
   9.220 +			ret = open_disk(s, dd, path);
   9.221 +			if (ret)
   9.222 +				goto params_done;
   9.223  
   9.224 -			entry = add_fd_entry(0, io_fd, s);
   9.225 +			entry = add_fd_entry(0, s);
   9.226  			entry->cookie = msg->cookie;
   9.227 -			DPRINTF("Entered cookie %d\n",entry->cookie);
   9.228 +			DPRINTF("Entered cookie %d\n", entry->cookie);
   9.229  			
   9.230  			memset(buf, 0x00, MSG_SIZE); 
   9.231  			
   9.232 @@ -323,13 +403,12 @@ static int read_msg(char *buf)
   9.233  			free(path);
   9.234  			return 1;
   9.235  			
   9.236 -			
   9.237 -			
   9.238  		case CTLMSG_NEWDEV:
   9.239  			msg_dev = (msg_newdev_t *)(buf + sizeof(msg_hdr_t));
   9.240  
   9.241  			s = get_state(msg->cookie);
   9.242 -			DPRINTF("Retrieving state, cookie %d.....[%s]\n",msg->cookie, (s == NULL ? "FAIL":"OK"));
   9.243 +			DPRINTF("Retrieving state, cookie %d.....[%s]\n",
   9.244 +				msg->cookie, (s == NULL ? "FAIL":"OK"));
   9.245  			if (s != NULL) {
   9.246  				ret = ((map_new_dev(s, msg_dev->devnum) 
   9.247  					== msg_dev->devnum ? 0: -1));
   9.248 @@ -397,49 +476,75 @@ static inline void kick_responses(struct
   9.249  	}
   9.250  }
   9.251  
   9.252 -void io_done(struct td_state *s, int sid)
   9.253 +void io_done(struct disk_driver *dd, int sid)
   9.254  {
   9.255 -	struct tap_disk *drv = s->drv;
   9.256 +	struct tap_disk *drv = dd->drv;
   9.257  
   9.258  	if (!run) return; /*We have received signal to close*/
   9.259  
   9.260 -	if (drv->td_do_callbacks(s, sid) > 0) kick_responses(s);
   9.261 +	if (drv->td_do_callbacks(dd, sid) > 0) kick_responses(dd->td_state);
   9.262  
   9.263  	return;
   9.264  }
   9.265  
   9.266 -int send_responses(struct td_state *s, int res, int idx, void *private)
   9.267 +static inline uint64_t
   9.268 +segment_start(blkif_request_t *req, int sidx)
   9.269  {
   9.270 +	int i;
   9.271 +	uint64_t start = req->sector_number;
   9.272 +
   9.273 +	for (i = 0; i < sidx; i++) 
   9.274 +		start += (req->seg[i].last_sect - req->seg[i].first_sect + 1);
   9.275 +
   9.276 +	return start;
   9.277 +}
   9.278 +
   9.279 +uint64_t sends, responds;
   9.280 +int send_responses(struct disk_driver *dd, int res, 
   9.281 +		   uint64_t sector, int nr_secs, int idx, void *private)
   9.282 +{
   9.283 +	pending_req_t   *preq;
   9.284  	blkif_request_t *req;
   9.285  	int responses_queued = 0;
   9.286 +	struct td_state *s = dd->td_state;
   9.287  	blkif_t *blkif = s->blkif;
   9.288 +	int sidx = (int)private, secs_done = nr_secs;
   9.289  
   9.290 -	req   = &blkif->pending_list[idx].req;
   9.291 -			
   9.292 -	if ( (idx > MAX_REQUESTS-1) || 
   9.293 -	    (blkif->pending_list[idx].count == 0) )
   9.294 +	if ( (idx > MAX_REQUESTS-1) )
   9.295  	{
   9.296  		DPRINTF("invalid index returned(%u)!\n", idx);
   9.297  		return 0;
   9.298  	}
   9.299 -	
   9.300 -	if (res != 0) {
   9.301 -	        blkif->pending_list[idx].status = BLKIF_RSP_ERROR;
   9.302 +	preq = &blkif->pending_list[idx];
   9.303 +	req  = &preq->req;
   9.304 +
   9.305 +	if (res == BLK_NOT_ALLOCATED) {
   9.306 +		res = do_cow_read(dd, req, sidx, sector, nr_secs);
   9.307 +		if (res >= 0) {
   9.308 +			secs_done = res;
   9.309 +			res = 0;
   9.310 +		} else
   9.311 +			secs_done = 0;
   9.312  	}
   9.313  
   9.314 -	blkif->pending_list[idx].count--;
   9.315 +	preq->secs_pending -= secs_done;
   9.316 +
   9.317 +	if (res == -EBUSY && preq->submitting) 
   9.318 +		return -EBUSY;  /* propagate -EBUSY back to higher layers */
   9.319 +	if (res) 
   9.320 +		preq->status = BLKIF_RSP_ERROR;
   9.321  	
   9.322 -	if (blkif->pending_list[idx].count == 0) 
   9.323 +	if (!preq->submitting && preq->secs_pending == 0) 
   9.324  	{
   9.325  		blkif_request_t tmp;
   9.326  		blkif_response_t *rsp;
   9.327 -		
   9.328 -		tmp = blkif->pending_list[idx].req;
   9.329 +
   9.330 +		tmp = preq->req;
   9.331  		rsp = (blkif_response_t *)req;
   9.332  		
   9.333  		rsp->id = tmp.id;
   9.334  		rsp->operation = tmp.operation;
   9.335 -		rsp->status = blkif->pending_list[idx].status;
   9.336 +		rsp->status = preq->status;
   9.337  		
   9.338  		write_rsp_to_ring(s, rsp);
   9.339  		responses_queued++;
   9.340 @@ -447,15 +552,51 @@ int send_responses(struct td_state *s, i
   9.341  	return responses_queued;
   9.342  }
   9.343  
   9.344 +int do_cow_read(struct disk_driver *dd, blkif_request_t *req, 
   9.345 +		int sidx, uint64_t sector, int nr_secs)
   9.346 +{
   9.347 +	char *page;
   9.348 +	int ret, early;
   9.349 +	uint64_t seg_start, seg_end;
   9.350 +	struct td_state  *s = dd->td_state;
   9.351 +	tapdev_info_t *info = s->ring_info;
   9.352 +	struct disk_driver *parent = dd->next;
   9.353 +	
   9.354 +	seg_start = segment_start(req, sidx);
   9.355 +	seg_end   = seg_start + req->seg[sidx].last_sect + 1;
   9.356 +	
   9.357 +	ASSERT(sector >= seg_start && sector + nr_secs <= seg_end);
   9.358 +
   9.359 +	page  = (char *)MMAP_VADDR(info->vstart, 
   9.360 +				   (unsigned long)req->id, sidx);
   9.361 +	page += (req->seg[sidx].first_sect << SECTOR_SHIFT);
   9.362 +	page += ((sector - seg_start) << SECTOR_SHIFT);
   9.363 +
   9.364 +	if (!parent) {
   9.365 +		memset(page, 0, nr_secs << SECTOR_SHIFT);
   9.366 +		return nr_secs;
   9.367 +	}
   9.368 +
   9.369 +	/* reissue request to backing file */
   9.370 +	ret = parent->drv->td_queue_read(parent, sector, nr_secs,
   9.371 +					 page, send_responses, 
   9.372 +					 req->id, (void *)sidx);
   9.373 +	if (ret > 0)
   9.374 +		parent->early += ret;
   9.375 +
   9.376 +	return ((ret >= 0) ? 0 : ret);
   9.377 +}
   9.378 +
   9.379  static void get_io_request(struct td_state *s)
   9.380  {
   9.381 -	RING_IDX          rp, rc, j, i, ret;
   9.382 +	RING_IDX          rp, rc, j, i;
   9.383  	blkif_request_t  *req;
   9.384 -	int idx, nsects;
   9.385 +	int idx, nsects, ret;
   9.386  	uint64_t sector_nr;
   9.387  	char *page;
   9.388  	int early = 0; /* count early completions */
   9.389 -	struct tap_disk *drv = s->drv;
   9.390 +	struct disk_driver *dd = s->disks;
   9.391 +	struct tap_disk *drv   = dd->drv;
   9.392  	blkif_t *blkif = s->blkif;
   9.393  	tapdev_info_t *info = s->ring_info;
   9.394  	int page_size = getpagesize();
   9.395 @@ -466,23 +607,33 @@ static void get_io_request(struct td_sta
   9.396  	rmb();
   9.397  	for (j = info->fe_ring.req_cons; j != rp; j++)
   9.398  	{
   9.399 -		int done = 0; 
   9.400 +		int done = 0, start_seg = 0; 
   9.401  
   9.402  		req = NULL;
   9.403  		req = RING_GET_REQUEST(&info->fe_ring, j);
   9.404  		++info->fe_ring.req_cons;
   9.405  		
   9.406  		if (req == NULL) continue;
   9.407 -		
   9.408 +
   9.409  		idx = req->id;
   9.410 -		ASSERT(blkif->pending_list[idx].count == 0);
   9.411 -		memcpy(&blkif->pending_list[idx].req, req, sizeof(*req));
   9.412 -		blkif->pending_list[idx].status = BLKIF_RSP_OKAY;
   9.413 -		blkif->pending_list[idx].count = req->nr_segments;
   9.414  
   9.415 -		sector_nr = req->sector_number;
   9.416 +		if (info->busy.req) {
   9.417 +			/* continue where we left off last time */
   9.418 +			ASSERT(info->busy.req == req);
   9.419 +			start_seg = info->busy.seg_idx;
   9.420 +			sector_nr = segment_start(req, start_seg);
   9.421 +			info->busy.seg_idx = 0;
   9.422 +			info->busy.req     = NULL;
   9.423 +		} else {
   9.424 +			ASSERT(blkif->pending_list[idx].secs_pending == 0);
   9.425 +			memcpy(&blkif->pending_list[idx].req, 
   9.426 +			       req, sizeof(*req));
   9.427 +			blkif->pending_list[idx].status = BLKIF_RSP_OKAY;
   9.428 +			blkif->pending_list[idx].submitting = 1;
   9.429 +			sector_nr = req->sector_number;
   9.430 +		}
   9.431  
   9.432 -		for (i = 0; i < req->nr_segments; i++) {
   9.433 +		for (i = start_seg; i < req->nr_segments; i++) {
   9.434  			nsects = req->seg[i].last_sect - 
   9.435  				 req->seg[i].first_sect + 1;
   9.436  	
   9.437 @@ -508,31 +659,37 @@ static void get_io_request(struct td_sta
   9.438  					(long long unsigned) sector_nr);
   9.439  				continue;
   9.440  			}
   9.441 -			
   9.442 +
   9.443 +			blkif->pending_list[idx].secs_pending += nsects;
   9.444 +
   9.445  			switch (req->operation) 
   9.446  			{
   9.447  			case BLKIF_OP_WRITE:
   9.448 -				ret = drv->td_queue_write(s, sector_nr,
   9.449 -						nsects, page, send_responses, 
   9.450 -						idx, NULL);
   9.451 -				if (ret > 0) early += ret;
   9.452 +				ret = drv->td_queue_write(dd, sector_nr,
   9.453 +							  nsects, page, 
   9.454 +							  send_responses,
   9.455 +							  idx, (void *)i);
   9.456 +				if (ret > 0) dd->early += ret;
   9.457  				else if (ret == -EBUSY) {
   9.458 -					/*
   9.459 -					 * TODO: Sector is locked         *
   9.460 -					 * Need to put req back on queue  *
   9.461 -					 */
   9.462 +					/* put req back on queue */
   9.463 +					--info->fe_ring.req_cons;
   9.464 +					info->busy.req     = req;
   9.465 +					info->busy.seg_idx = i;
   9.466 +					goto out;
   9.467  				}
   9.468  				break;
   9.469  			case BLKIF_OP_READ:
   9.470 -				ret = drv->td_queue_read(s, sector_nr,
   9.471 -						nsects, page, send_responses, 
   9.472 -						idx, NULL);
   9.473 -				if (ret > 0) early += ret;
   9.474 +				ret = drv->td_queue_read(dd, sector_nr,
   9.475 +							 nsects, page, 
   9.476 +							 send_responses,
   9.477 +							 idx, (void *)i);
   9.478 +				if (ret > 0) dd->early += ret;
   9.479  				else if (ret == -EBUSY) {
   9.480 -					/*
   9.481 -					 * TODO: Sector is locked         *
   9.482 -					 * Need to put req back on queue  *
   9.483 -					 */
   9.484 +					/* put req back on queue */
   9.485 +					--info->fe_ring.req_cons;
   9.486 +					info->busy.req     = req;
   9.487 +					info->busy.seg_idx = i;
   9.488 +					goto out;
   9.489  				}
   9.490  				break;
   9.491  			default:
   9.492 @@ -541,14 +698,22 @@ static void get_io_request(struct td_sta
   9.493  			}
   9.494  			sector_nr += nsects;
   9.495  		}
   9.496 +		blkif->pending_list[idx].submitting = 0;
   9.497 +		/* force write_rsp_to_ring for synchronous case */
   9.498 +		if (blkif->pending_list[idx].secs_pending == 0)
   9.499 +			dd->early += send_responses(dd, 0, 0, 0, idx, (void *)0);
   9.500  	}
   9.501  
   9.502 + out:
   9.503  	/*Batch done*/
   9.504 -	drv->td_submit(s);
   9.505 -	
   9.506 -	if (early > 0) 
   9.507 -		io_done(s,10);
   9.508 -		
   9.509 +	td_for_each_disk(s, dd) {
   9.510 +		dd->early += dd->drv->td_submit(dd);
   9.511 +		if (dd->early > 0) {
   9.512 +			io_done(dd, 10);
   9.513 +			dd->early = 0;
   9.514 +		}
   9.515 +	}
   9.516 +
   9.517  	return;
   9.518  }
   9.519  
   9.520 @@ -558,10 +723,9 @@ int main(int argc, char *argv[])
   9.521  	char *p, *buf;
   9.522  	fd_set readfds, writefds;	
   9.523  	fd_list_entry_t *ptr;
   9.524 -	struct tap_disk *drv;
   9.525  	struct td_state *s;
   9.526  	char openlogbuf[128];
   9.527 -	
   9.528 +
   9.529  	if (argc != 3) usage();
   9.530  
   9.531  	daemonize();
   9.532 @@ -573,12 +737,12 @@ int main(int argc, char *argv[])
   9.533  	signal (SIGINT, sig_handler);
   9.534  
   9.535  	/*Open the control channel*/
   9.536 -	fds[READ] = open(argv[1],O_RDWR|O_NONBLOCK);
   9.537 +	fds[READ]  = open(argv[1],O_RDWR|O_NONBLOCK);
   9.538  	fds[WRITE] = open(argv[2],O_RDWR|O_NONBLOCK);
   9.539  
   9.540  	if ( (fds[READ] < 0) || (fds[WRITE] < 0) ) 
   9.541  	{
   9.542 -		DPRINTF("FD open failed [%d,%d]\n",fds[READ], fds[WRITE]);
   9.543 +		DPRINTF("FD open failed [%d,%d]\n", fds[READ], fds[WRITE]);
   9.544  		exit(-1);
   9.545  	}
   9.546  
   9.547 @@ -608,11 +772,22 @@ int main(int argc, char *argv[])
   9.548  		{
   9.549  			ptr = fd_start;
   9.550  			while (ptr != NULL) {
   9.551 -				if (FD_ISSET(ptr->tap_fd, &readfds)) 
   9.552 +				int progress_made = 0;
   9.553 +				struct disk_driver *dd;
   9.554 +				tapdev_info_t *info = ptr->s->ring_info;
   9.555 +
   9.556 +				td_for_each_disk(ptr->s, dd) {
   9.557 +					if (dd->io_fd[READ] &&
   9.558 +					    FD_ISSET(dd->io_fd[READ], 
   9.559 +						     &readfds)) {
   9.560 +						io_done(dd, READ);
   9.561 +						progress_made = 1;
   9.562 +					}
   9.563 +				}
   9.564 +
   9.565 +				if (FD_ISSET(ptr->tap_fd, &readfds) ||
   9.566 +				    (info->busy.req && progress_made))
   9.567  					get_io_request(ptr->s);
   9.568 -				if (ptr->io_fd[READ] && 
   9.569 -						FD_ISSET(ptr->io_fd[READ], &readfds)) 
   9.570 -					io_done(ptr->s, READ);
   9.571  
   9.572  				ptr = ptr->next;
   9.573  			}
   9.574 @@ -628,11 +803,8 @@ int main(int argc, char *argv[])
   9.575  	ptr = fd_start;
   9.576  	while (ptr != NULL) {
   9.577  		s = ptr->s;
   9.578 -		drv = s->drv;
   9.579  
   9.580  		unmap_disk(s);
   9.581 -		drv->td_close(s);
   9.582 -		free(s->private);
   9.583  		free(s->blkif);
   9.584  		free(s->ring_info);
   9.585  		free(s);

    10.1 --- a/tools/blktap/drivers/tapdisk.h	Fri Feb 16 16:34:28 2007 +0000
    10.2 +++ b/tools/blktap/drivers/tapdisk.h	Fri Feb 16 20:31:27 2007 -0800
    10.3 @@ -43,6 +43,9 @@
    10.4   *   - The fd used for poll is an otherwise unused pipe, which allows poll to 
    10.5   *     be safely called without ever returning anything.
    10.6   * 
    10.7 + * NOTE: tapdisk uses the number of sectors submitted per request as a 
    10.8 + * ref count.  Plugins must use the callback function to communicate the
    10.9 + * completion--or error--of every sector submitted to them.
   10.10   */
   10.11  
   10.12  #ifndef TAPDISK_H_
   10.13 @@ -65,39 +68,55 @@
   10.14  #define SECTOR_SHIFT             9
   10.15  #define DEFAULT_SECTOR_SIZE    512
   10.16  
   10.17 +#define MAX_IOFD                 2
   10.18 +
   10.19 +#define BLK_NOT_ALLOCATED       99
   10.20 +
   10.21 +struct td_state;
   10.22 +struct tap_disk;
   10.23 +
   10.24 +struct disk_driver {
   10.25 +	int early;
   10.26 +	void *private;
   10.27 +	int io_fd[MAX_IOFD];
   10.28 +	struct tap_disk *drv;
   10.29 +	struct td_state *td_state;
   10.30 +	struct disk_driver *next;
   10.31 +};
   10.32 +
   10.33  /* This structure represents the state of an active virtual disk.           */
   10.34  struct td_state {
   10.35 -	void *private;
   10.36 -	void *drv;
   10.37 +	struct disk_driver *disks;
   10.38  	void *blkif;
   10.39  	void *image;
   10.40  	void *ring_info;
   10.41  	void *fd_entry;
   10.42 -	char backing_file[1024]; /*Used by differencing disks, e.g. qcow*/
   10.43  	unsigned long      sector_size;
   10.44  	unsigned long long size;
   10.45  	unsigned int       info;
   10.46  };
   10.47  
   10.48  /* Prototype of the callback to activate as requests complete.              */
   10.49 -typedef int (*td_callback_t)(struct td_state *s, int res, int id, void *prv);
   10.50 +typedef int (*td_callback_t)(struct disk_driver *dd, int res, uint64_t sector,
   10.51 +			     int nb_sectors, int id, void *private);
   10.52  
   10.53  /* Structure describing the interface to a virtual disk implementation.     */
   10.54  /* See note at the top of this file describing this interface.              */
   10.55  struct tap_disk {
   10.56  	const char *disk_type;
   10.57  	int private_data_size;
   10.58 -	int (*td_open)        (struct td_state *s, const char *name);
   10.59 -	int (*td_queue_read)  (struct td_state *s, uint64_t sector,
   10.60 -			       int nb_sectors, char *buf, td_callback_t cb,
   10.61 +	int (*td_open)        (struct disk_driver *dd, const char *name);
   10.62 +	int (*td_queue_read)  (struct disk_driver *dd, uint64_t sector,
   10.63 +			       int nb_sectors, char *buf, td_callback_t cb, 
   10.64  			       int id, void *prv);
   10.65 -	int (*td_queue_write) (struct td_state *s, uint64_t sector,
   10.66 -			       int nb_sectors, char *buf, td_callback_t cb,
   10.67 +	int (*td_queue_write) (struct disk_driver *dd, uint64_t sector,
   10.68 +			       int nb_sectors, char *buf, td_callback_t cb, 
   10.69  			       int id, void *prv);
   10.70 -	int (*td_submit)      (struct td_state *s);
   10.71 -	int *(*td_get_fd)      (struct td_state *s);
   10.72 -	int (*td_close)       (struct td_state *s);
   10.73 -	int (*td_do_callbacks)(struct td_state *s, int sid);
   10.74 +	int (*td_submit)      (struct disk_driver *dd);
   10.75 +	int (*td_has_parent)  (struct disk_driver *dd);
   10.76 +	int (*td_get_parent)  (struct disk_driver *dd, struct disk_driver *p);
   10.77 +	int (*td_close)       (struct disk_driver *dd);
   10.78 +	int (*td_do_callbacks)(struct disk_driver *dd, int sid);
   10.79  };
   10.80  
   10.81  typedef struct disk_info {
   10.82 @@ -119,14 +138,13 @@ extern struct tap_disk tapdisk_vmdk;
   10.83  extern struct tap_disk tapdisk_ram;
   10.84  extern struct tap_disk tapdisk_qcow;
   10.85  
   10.86 -#define MAX_DISK_TYPES  20
   10.87 -#define MAX_IOFD        2
   10.88 +#define MAX_DISK_TYPES     20
   10.89  
   10.90 -#define DISK_TYPE_AIO   0
   10.91 -#define DISK_TYPE_SYNC  1
   10.92 -#define DISK_TYPE_VMDK  2
   10.93 -#define DISK_TYPE_RAM   3
   10.94 -#define DISK_TYPE_QCOW  4
   10.95 +#define DISK_TYPE_AIO      0
   10.96 +#define DISK_TYPE_SYNC     1
   10.97 +#define DISK_TYPE_VMDK     2
   10.98 +#define DISK_TYPE_RAM      3
   10.99 +#define DISK_TYPE_QCOW     4
  10.100  
  10.101  
  10.102  /*Define Individual Disk Parameters here */
  10.103 @@ -197,12 +215,10 @@ typedef struct driver_list_entry {
  10.104  typedef struct fd_list_entry {
  10.105  	int cookie;
  10.106  	int  tap_fd;
  10.107 -	int  io_fd[MAX_IOFD];
  10.108  	struct td_state *s;
  10.109  	struct fd_list_entry **pprev, *next;
  10.110  } fd_list_entry_t;
  10.111  
  10.112  int qcow_create(const char *filename, uint64_t total_size,
  10.113  		const char *backing_file, int flags);
  10.114 -
  10.115  #endif /*TAPDISK_H_*/

    11.1 --- a/tools/blktap/lib/blktaplib.h	Fri Feb 16 16:34:28 2007 +0000
    11.2 +++ b/tools/blktap/lib/blktaplib.h	Fri Feb 16 20:31:27 2007 -0800
    11.3 @@ -91,8 +91,9 @@ struct blkif;
    11.4  
    11.5  typedef struct {
    11.6  	blkif_request_t  req;
    11.7 -	struct blkif         *blkif;
    11.8 -	int              count;
    11.9 +	struct blkif    *blkif;
   11.10 +	int              submitting;
   11.11 +	int              secs_pending;
   11.12          int16_t          status;
   11.13  } pending_req_t;
   11.14  
   11.15 @@ -116,7 +117,7 @@ typedef struct blkif {
   11.16  	
   11.17  	void *prv;  /* device-specific data */
   11.18  	void *info; /*Image parameter passing */
   11.19 -	pending_req_t    pending_list[MAX_REQUESTS];
   11.20 +	pending_req_t pending_list[MAX_REQUESTS];
   11.21  	int devnum;
   11.22  	int fds[2];
   11.23  	int be_id;
   11.24 @@ -141,6 +142,11 @@ int blkif_init(blkif_t *blkif, long int 
   11.25  void free_blkif(blkif_t *blkif);
   11.26  void __init_blkif(void);
   11.27  
   11.28 +typedef struct busy_state {
   11.29 +	int seg_idx;
   11.30 +	blkif_request_t *req;
   11.31 +} busy_state_t;
   11.32 +
   11.33  typedef struct tapdev_info {
   11.34  	int fd;
   11.35  	char *mem;
   11.36 @@ -148,6 +154,7 @@ typedef struct tapdev_info {
   11.37  	blkif_back_ring_t  fe_ring;
   11.38  	unsigned long vstart;
   11.39  	blkif_t *blkif;
   11.40 +	busy_state_t busy;
   11.41  } tapdev_info_t;
   11.42  
   11.43  typedef struct domid_translate {

    12.1 --- a/tools/blktap/lib/xs_api.c	Fri Feb 16 16:34:28 2007 +0000
    12.2 +++ b/tools/blktap/lib/xs_api.c	Fri Feb 16 20:31:27 2007 -0800
    12.3 @@ -311,8 +311,8 @@ int unregister_xenbus_watch(struct xs_ha
    12.4  	}
    12.5  
    12.6  	if (!xs_unwatch(h, watch->node, token))
    12.7 -		DPRINTF("XENBUS Failed to release watch %s: %i\n",
    12.8 -			watch->node, er);
    12.9 +		DPRINTF("XENBUS Failed to release watch %s\n",
   12.10 +			watch->node);
   12.11  
   12.12  	list_del(&watch->list);
   12.13  	
   12.14 @@ -351,9 +351,9 @@ int xs_fire_next_watch(struct xs_handle 
   12.15  	
   12.16  	node  = res[XS_WATCH_PATH];
   12.17  	token = res[XS_WATCH_TOKEN];
   12.18 -	
   12.19 +
   12.20  	w = find_watch(token);
   12.21 -	if (w)
   12.22 +	if (w) 
   12.23  		w->callback(h, w, node);
   12.24  
   12.25  	free(res);