Re: [PATCH-v2 13/17] target/file: Add DIF protection support to fd_execute_rw
From: Sagi Grimberg
Date: Sun Jan 19 2014 - 07:37:59 EST
On 1/19/2014 4:44 AM, Nicholas A. Bellinger wrote:
From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
This patch adds support for DIF protection into fd_execute_rw() code
for WRITE/READ I/O using sbc_dif_verify_[write,read]() logic.
It adds fd_do_prot_rw() for handling interface with FILEIO PI, and
uses a locally allocated fd_prot->prot_buf + fd_prot->prot_sg for
interacting with SBC DIF verify emulation code.
Cc: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Cc: Sagi Grimberg <sagig@xxxxxxxxxxxx>
Cc: Or Gerlitz <ogerlitz@xxxxxxxxxxxx>
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
---
drivers/target/target_core_file.c | 119 ++++++++++++++++++++++++++++++++++++-
drivers/target/target_core_file.h | 5 ++
2 files changed, 123 insertions(+), 1 deletion(-)
diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
index 119d519..aaba7c5 100644
--- a/drivers/target/target_core_file.c
+++ b/drivers/target/target_core_file.c
@@ -257,6 +257,72 @@ static void fd_free_device(struct se_device *dev)
kfree(fd_dev);
}
+static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot,
+ int is_write)
+{
+ 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;
+
+ prot_size = (cmd->data_length / se_dev->dev_attrib.block_size) *
+ se_dev->prot_length;
+
+ if (!is_write) {
+ fd_prot->prot_buf = vzalloc(prot_size);
+ if (!fd_prot->prot_buf) {
+ pr_err("Unable to allocate fd_prot->prot_buf\n");
+ return -ENOMEM;
+ }
+ 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);
+ if (!fd_prot->prot_sg) {
+ pr_err("Unable to allocate fd_prot->prot_sg\n");
+ vfree(fd_prot->prot_buf);
+ return -ENOMEM;
+ }
+ 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;
+ }
+ }
+
+ if (is_write) {
+ rc = kernel_write(prot_fd, fd_prot->prot_buf, prot_size, pos);
+ if (rc < 0 || prot_size != rc) {
+ pr_err("kernel_write() for fd_do_prot_rw failed:"
+ " %d\n", rc);
+ ret = -EINVAL;
+ }
+ } else {
+ rc = kernel_read(prot_fd, pos, fd_prot->prot_buf, prot_size);
+ if (rc < 0) {
+ pr_err("kernel_read() for fd_do_prot_rw failed:"
+ " %d\n", rc);
+ ret = -EINVAL;
+ }
+ }
+
+ if (is_write || ret < 0) {
+ kfree(fd_prot->prot_sg);
+ vfree(fd_prot->prot_buf);
+ }
+
+ return ret;
+}
+
static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
u32 sgl_nents, int is_write)
{
@@ -551,6 +617,8 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
enum dma_data_direction data_direction)
{
struct se_device *dev = cmd->se_dev;
+ struct fd_prot fd_prot;
+ sense_reason_t rc;
int ret = 0;
/*
@@ -558,8 +626,48 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
* physical memory addresses to struct iovec virtual memory.
*/
if (data_direction == DMA_FROM_DEVICE) {
Maybe its better to export this one to a separate function?
fd_execute_prot_rw()? just a nit...
+ memset(&fd_prot, 0, sizeof(struct fd_prot));
+
+ if (cmd->prot_type) {
+ ret = fd_do_prot_rw(cmd, &fd_prot, false);
+ if (ret < 0)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
+
+ if (ret > 0 && cmd->prot_type) {
+ u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
+
+ rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors,
+ 0, fd_prot.prot_sg, 0);
+ if (rc) {
+ kfree(fd_prot.prot_sg);
+ vfree(fd_prot.prot_buf);
+ return rc;
+ }
+ kfree(fd_prot.prot_sg);
+ vfree(fd_prot.prot_buf);
+ }
} else {
+ memset(&fd_prot, 0, sizeof(struct fd_prot));
+
+ if (cmd->prot_type) {
+ u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
+
+ ret = fd_do_prot_rw(cmd, &fd_prot, false);
+ if (ret < 0)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+ rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors,
+ 0, fd_prot.prot_sg, 0);
+ if (rc) {
+ kfree(fd_prot.prot_sg);
+ vfree(fd_prot.prot_buf);
+ return rc;
+ }
+ }
+
ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
/*
* Perform implicit vfs_fsync_range() for fd_do_writev() ops
@@ -576,10 +684,19 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
vfs_fsync_range(fd_dev->fd_file, start, end, 1);
}
+
+ if (ret > 0 && cmd->prot_type) {
+ ret = fd_do_prot_rw(cmd, &fd_prot, true);
+ if (ret < 0)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
}
- if (ret < 0)
+ if (ret < 0) {
+ kfree(fd_prot.prot_sg);
+ vfree(fd_prot.prot_buf);
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
if (ret)
target_complete_cmd(cmd, SAM_STAT_GOOD);
diff --git a/drivers/target/target_core_file.h b/drivers/target/target_core_file.h
index 583691e..97e5e7d 100644
--- a/drivers/target/target_core_file.h
+++ b/drivers/target/target_core_file.h
@@ -18,6 +18,11 @@
#define FDBD_HAS_BUFFERED_IO_WCE 0x04
#define FDBD_FORMAT_UNIT_SIZE 2048
+struct fd_prot {
+ unsigned char *prot_buf;
+ struct scatterlist *prot_sg;
+ u32 prot_sg_nents;
+};
struct fd_dev {
struct se_device dev;
--
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