| Message ID | 1428934918-4004-2-git-send-email-akinobu.mita@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, 2015-04-13 at 23:21 +0900, Akinobu Mita wrote: > In fd_do_prot_rw(), it allocates prot_buf which is used to copy from > se_cmd->t_prot_sg by sbc_dif_copy_prot(). The SG table for prot_buf > is also initialized by allocating 'se_cmd->t_prot_nents' entries of > scatterlist and setting the data length of each entry to PAGE_SIZE > at most. > > However if se_cmd->t_prot_sg contains a clustered entry (i.e. > sg->length > PAGE_SIZE), the SG table for prot_buf can't be > initialized correctly and sbc_dif_copy_prot() can't copy to prot_buf. > (This actually happened with TCM loopback fabric module) > > As prot_buf is allocated by kzalloc() and it's physically contiguous, > we only need a single scatterlist entry. > > Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> > Cc: Nicholas Bellinger <nab@linux-iscsi.org> > Cc: Sagi Grimberg <sagig@mellanox.com> > Cc: "Martin K. Petersen" <martin.petersen@oracle.com> > Cc: Christoph Hellwig <hch@lst.de> > Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> > Cc: target-devel@vger.kernel.org > Cc: linux-scsi@vger.kernel.org > --- > drivers/target/target_core_file.c | 21 ++++++--------------- > 1 file changed, 6 insertions(+), 15 deletions(-) > Applied to target-pending/for-next, with CC' for v3.14.y stable. Thanks Akinobu! -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c index 8ca1883..4c7a6c8 100644 --- a/drivers/target/target_core_file.c +++ b/drivers/target/target_core_file.c @@ -264,11 +264,10 @@ static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot, struct se_device *se_dev = cmd->se_dev; struct fd_dev *dev = FD_DEV(se_dev); struct file *prot_fd = dev->fd_prot_file; - struct scatterlist *sg; loff_t pos = (cmd->t_task_lba * se_dev->prot_length); unsigned char *buf; - u32 prot_size, len, size; - int rc, ret = 1, i; + u32 prot_size; + int rc, ret = 1; prot_size = (cmd->data_length / se_dev->dev_attrib.block_size) * se_dev->prot_length; @@ -281,24 +280,16 @@ static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot, } buf = fd_prot->prot_buf; - fd_prot->prot_sg_nents = cmd->t_prot_nents; - fd_prot->prot_sg = kzalloc(sizeof(struct scatterlist) * - fd_prot->prot_sg_nents, GFP_KERNEL); + fd_prot->prot_sg_nents = 1; + fd_prot->prot_sg = kzalloc(sizeof(struct scatterlist), + GFP_KERNEL); if (!fd_prot->prot_sg) { pr_err("Unable to allocate fd_prot->prot_sg\n"); kfree(fd_prot->prot_buf); return -ENOMEM; } sg_init_table(fd_prot->prot_sg, fd_prot->prot_sg_nents); - size = prot_size; - - for_each_sg(fd_prot->prot_sg, sg, fd_prot->prot_sg_nents, i) { - - len = min_t(u32, PAGE_SIZE, size); - sg_set_buf(sg, buf, len); - size -= len; - buf += len; - } + sg_set_buf(fd_prot->prot_sg, buf, prot_size); } if (is_write) {
In fd_do_prot_rw(), it allocates prot_buf which is used to copy from se_cmd->t_prot_sg by sbc_dif_copy_prot(). The SG table for prot_buf is also initialized by allocating 'se_cmd->t_prot_nents' entries of scatterlist and setting the data length of each entry to PAGE_SIZE at most. However if se_cmd->t_prot_sg contains a clustered entry (i.e. sg->length > PAGE_SIZE), the SG table for prot_buf can't be initialized correctly and sbc_dif_copy_prot() can't copy to prot_buf. (This actually happened with TCM loopback fabric module) As prot_buf is allocated by kzalloc() and it's physically contiguous, we only need a single scatterlist entry. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Nicholas Bellinger <nab@linux-iscsi.org> Cc: Sagi Grimberg <sagig@mellanox.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Christoph Hellwig <hch@lst.de> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: target-devel@vger.kernel.org Cc: linux-scsi@vger.kernel.org --- drivers/target/target_core_file.c | 21 ++++++--------------- 1 file changed, 6 insertions(+), 15 deletions(-)