| Message ID | 20190801234514.7941-2-logang@deltatee.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | nvmet: add target passthru commands support | expand |
On 8/2/2019 2:45 AM, Logan Gunthorpe wrote: > nvme_ctrl_get_by_path() is analagous to blkdev_get_by_path() except it > gets a struct nvme_ctrl from the path to its char dev (/dev/nvme0). > It makes use of filp_open() to open the file and uses the private > data to obtain a pointer to the struct nvme_ctrl. If the fops of the > file do not match, -EINVAL is returned. > > The purpose of this function is to support NVMe-OF target passthru. > > Signed-off-by: Logan Gunthorpe <logang@deltatee.com> > --- > drivers/nvme/host/core.c | 24 ++++++++++++++++++++++++ > drivers/nvme/host/nvme.h | 2 ++ > 2 files changed, 26 insertions(+) Looks good, Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
On 8/2/2019 2:45 AM, Logan Gunthorpe wrote: > nvme_ctrl_get_by_path() is analagous to blkdev_get_by_path() except it > gets a struct nvme_ctrl from the path to its char dev (/dev/nvme0). > It makes use of filp_open() to open the file and uses the private > data to obtain a pointer to the struct nvme_ctrl. If the fops of the > file do not match, -EINVAL is returned. > > The purpose of this function is to support NVMe-OF target passthru. > > Signed-off-by: Logan Gunthorpe <logang@deltatee.com> > --- > drivers/nvme/host/core.c | 24 ++++++++++++++++++++++++ > drivers/nvme/host/nvme.h | 2 ++ > 2 files changed, 26 insertions(+) > > diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c > index e6ee6f2a3da6..f72334f34a30 100644 > --- a/drivers/nvme/host/core.c > +++ b/drivers/nvme/host/core.c > @@ -2817,6 +2817,30 @@ static const struct file_operations nvme_dev_fops = { > .compat_ioctl = nvme_dev_ioctl, > }; > > +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path) > +{ > + struct nvme_ctrl *ctrl; > + struct file *f; > + > + f = filp_open(path, O_RDWR, 0); > + if (IS_ERR(f)) > + return ERR_CAST(f); > + > + if (f->f_op != &nvme_dev_fops) { > + ctrl = ERR_PTR(-EINVAL); > + goto out_close; > + } Logan, this means that the PT is for nvme-pci and also nvme-fabrics as well. Is this the intention ? or we want to restrict it to pci only. > + > + ctrl = f->private_data; > + nvme_get_ctrl(ctrl); > + > +out_close: > + filp_close(f, NULL); > + > + return ctrl; > +} > +EXPORT_SYMBOL_GPL(nvme_ctrl_get_by_path); > + > static ssize_t nvme_sysfs_reset(struct device *dev, > struct device_attribute *attr, const char *buf, > size_t count) > diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h > index ecbd90c31d0d..7e827c9e892c 100644 > --- a/drivers/nvme/host/nvme.h > +++ b/drivers/nvme/host/nvme.h > @@ -484,6 +484,8 @@ int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp, > extern const struct attribute_group *nvme_ns_id_attr_groups[]; > extern const struct block_device_operations nvme_ns_head_ops; > > +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path); > + > #ifdef CONFIG_NVME_MULTIPATH > static inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl) > {
On 2019-08-15 5:46 a.m., Max Gurtovoy wrote: > > On 8/2/2019 2:45 AM, Logan Gunthorpe wrote: >> nvme_ctrl_get_by_path() is analagous to blkdev_get_by_path() except it >> gets a struct nvme_ctrl from the path to its char dev (/dev/nvme0). >> It makes use of filp_open() to open the file and uses the private >> data to obtain a pointer to the struct nvme_ctrl. If the fops of the >> file do not match, -EINVAL is returned. >> >> The purpose of this function is to support NVMe-OF target passthru. >> >> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> >> --- >> drivers/nvme/host/core.c | 24 ++++++++++++++++++++++++ >> drivers/nvme/host/nvme.h | 2 ++ >> 2 files changed, 26 insertions(+) >> >> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c >> index e6ee6f2a3da6..f72334f34a30 100644 >> --- a/drivers/nvme/host/core.c >> +++ b/drivers/nvme/host/core.c >> @@ -2817,6 +2817,30 @@ static const struct file_operations >> nvme_dev_fops = { >> .compat_ioctl = nvme_dev_ioctl, >> }; >> +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path) >> +{ >> + struct nvme_ctrl *ctrl; >> + struct file *f; >> + >> + f = filp_open(path, O_RDWR, 0); >> + if (IS_ERR(f)) >> + return ERR_CAST(f); >> + >> + if (f->f_op != &nvme_dev_fops) { >> + ctrl = ERR_PTR(-EINVAL); >> + goto out_close; >> + } > > Logan, > > this means that the PT is for nvme-pci and also nvme-fabrics as well. > > Is this the intention ? or we want to restrict it to pci only. Yes, in theory, someone could passthru an nvme-fabrics controller or they could passthru a passthru'd passthru'd nvme-fabrics controller. This probably isn't a good idea but I don't know that we need to specifically reject it. If you think we should I could figure out a way to filter by pci controllers only. Logan
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index e6ee6f2a3da6..f72334f34a30 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2817,6 +2817,30 @@ static const struct file_operations nvme_dev_fops = { .compat_ioctl = nvme_dev_ioctl, }; +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path) +{ + struct nvme_ctrl *ctrl; + struct file *f; + + f = filp_open(path, O_RDWR, 0); + if (IS_ERR(f)) + return ERR_CAST(f); + + if (f->f_op != &nvme_dev_fops) { + ctrl = ERR_PTR(-EINVAL); + goto out_close; + } + + ctrl = f->private_data; + nvme_get_ctrl(ctrl); + +out_close: + filp_close(f, NULL); + + return ctrl; +} +EXPORT_SYMBOL_GPL(nvme_ctrl_get_by_path); + static ssize_t nvme_sysfs_reset(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index ecbd90c31d0d..7e827c9e892c 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -484,6 +484,8 @@ int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp, extern const struct attribute_group *nvme_ns_id_attr_groups[]; extern const struct block_device_operations nvme_ns_head_ops; +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path); + #ifdef CONFIG_NVME_MULTIPATH static inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl) {
nvme_ctrl_get_by_path() is analagous to blkdev_get_by_path() except it gets a struct nvme_ctrl from the path to its char dev (/dev/nvme0). It makes use of filp_open() to open the file and uses the private data to obtain a pointer to the struct nvme_ctrl. If the fops of the file do not match, -EINVAL is returned. The purpose of this function is to support NVMe-OF target passthru. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> --- drivers/nvme/host/core.c | 24 ++++++++++++++++++++++++ drivers/nvme/host/nvme.h | 2 ++ 2 files changed, 26 insertions(+)