Re: [PATCH v2 13/38] cxlflash: Support adapter file descriptors for OCXL
> On Mar 22, 2018, at 12:12 PM, Frederic Barrat
> wrote:
>
>
>
> Le 26/02/2018 à 23:21, Uma Krishnan a écrit :
>> Allocate a file descriptor for an adapter context when requested. In order
>> to allocate inodes for the file descriptors, a pseudo filesystem is created
>> and used.
>> Signed-off-by: Uma Krishnan
>> Acked-by: Matthew R. Ochs
>> ---
>
>
> We've touched the subject before, and I don't have a magic solution, but it
> feels like something could be shared here with cxl, or maybe even other
> drivers?
>
Yes, perhaps we could look at refactoring in a future series.
> I only took a quick read of the inode allocator.
>
> Fred
>
>
>
>
>> drivers/scsi/cxlflash/ocxl_hw.c | 200
>>
>> drivers/scsi/cxlflash/ocxl_hw.h | 1 +
>> 2 files changed, 201 insertions(+)
>> diff --git a/drivers/scsi/cxlflash/ocxl_hw.c
>> b/drivers/scsi/cxlflash/ocxl_hw.c
>> index 6472210..59e9003 100644
>> --- a/drivers/scsi/cxlflash/ocxl_hw.c
>> +++ b/drivers/scsi/cxlflash/ocxl_hw.c
>> @@ -12,13 +12,144 @@
>> * 2 of the License, or (at your option) any later version.
>> */
>> +#include
>> #include
>> +#include
>> +#include
>> #include
>> #include "backend.h"
>> #include "ocxl_hw.h"
>> +/*
>> + * Pseudo-filesystem to allocate inodes.
>> + */
>> +
>> +#define OCXLFLASH_FS_MAGIC 0x1697698f
>> +
>> +static int ocxlflash_fs_cnt;
>> +static struct vfsmount *ocxlflash_vfs_mount;
>> +
>> +static const struct dentry_operations ocxlflash_fs_dops = {
>> +.d_dname= simple_dname,
>> +};
>> +
>> +/*
>> + * ocxlflash_fs_mount() - mount the pseudo-filesystem
>> + * @fs_type:File system type.
>> + * @flags: Flags for the filesystem.
>> + * @dev_name: Device name associated with the filesystem.
>> + * @data: Data pointer.
>> + *
>> + * Return: pointer to the directory entry structure
>> + */
>> +static struct dentry *ocxlflash_fs_mount(struct file_system_type *fs_type,
>> + int flags, const char *dev_name,
>> + void *data)
>> +{
>> +return mount_pseudo(fs_type, "ocxlflash:", NULL, &ocxlflash_fs_dops,
>> +OCXLFLASH_FS_MAGIC);
>> +}
>> +
>> +static struct file_system_type ocxlflash_fs_type = {
>> +.name = "ocxlflash",
>> +.owner = THIS_MODULE,
>> +.mount = ocxlflash_fs_mount,
>> +.kill_sb= kill_anon_super,
>> +};
>> +
>> +/*
>> + * ocxlflash_release_mapping() - release the memory mapping
>> + * @ctx:Context whose mapping is to be released.
>> + */
>> +static void ocxlflash_release_mapping(struct ocxlflash_context *ctx)
>> +{
>> +if (ctx->mapping)
>> +simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
>> +ctx->mapping = NULL;
>> +}
>> +
>> +/*
>> + * ocxlflash_getfile() - allocate pseudo filesystem, inode, and the file
>> + * @dev:Generic device of the host.
>> + * @name: Name of the pseudo filesystem.
>> + * @fops: File operations.
>> + * @priv: Private data.
>> + * @flags: Flags for the file.
>> + *
>> + * Return: pointer to the file on success, ERR_PTR on failure
>> + */
>> +static struct file *ocxlflash_getfile(struct device *dev, const char *name,
>> + const struct file_operations *fops,
>> + void *priv, int flags)
>> +{
>> +struct qstr this;
>> +struct path path;
>> +struct file *file;
>> +struct inode *inode = NULL;
>> +int rc;
>> +
>> +if (fops->owner && !try_module_get(fops->owner)) {
>> +dev_err(dev, "%s: Owner does not exist\n", __func__);
>> +rc = -ENOENT;
>> +goto err1;
>> +}
>> +
>> +rc = simple_pin_fs(&ocxlflash_fs_type, &ocxlflash_vfs_mount,
>> + &ocxlflash_fs_cnt);
>> +if (unlikely(rc < 0)) {
>> +dev_err(dev, "%s: Cannot mount ocxlflash pseudofs rc=%d\n",
>> +__func__, rc);
>> +goto err2;
>> +}
>> +
>> +inode = alloc_anon_inode(ocxlflash_vfs_mount->mnt_sb);
>> +if (IS_ERR(inode)) {
>> +rc = PTR_ERR(inode);
>> +dev_err(dev, "%s: alloc_anon_inode failed rc=%d\n",
>> +__func__, rc);
>> +goto err3;
>> +}
>> +
>> +this.name = name;
>> +this.len = strlen(name);
>> +this.hash = 0;
>> +path.dentry = d_alloc_pseudo(ocxlflash_vfs_mount->mnt_sb, &this);
>> +if (!path.dentry) {
>> +dev_err(dev, "%s: d_alloc_pseudo failed\n", __func__);
>> +rc = -ENOMEM;
>> +goto err4;
>> +}
>> +
>> +path.mnt = mntget(ocxlflash_vfs_mount);
>> +d_instantiate(path.dentry, inode);
>> +
>> +file = alloc_file(&path, OPEN_FMODE(flags), fops);
>> +if (IS_ERR(file)) {
>> +rc = PTR_ERR(file);
>> +dev_err(dev, "%s: alloc_file failed rc=%d\n",
>> +__func__, rc);
>> +goto
Re: [PATCH v2 13/38] cxlflash: Support adapter file descriptors for OCXL
Le 26/02/2018 à 23:21, Uma Krishnan a écrit :
Allocate a file descriptor for an adapter context when requested. In order
to allocate inodes for the file descriptors, a pseudo filesystem is created
and used.
Signed-off-by: Uma Krishnan
Acked-by: Matthew R. Ochs
---
We've touched the subject before, and I don't have a magic solution, but
it feels like something could be shared here with cxl, or maybe even
other drivers?
I only took a quick read of the inode allocator.
Fred
drivers/scsi/cxlflash/ocxl_hw.c | 200
drivers/scsi/cxlflash/ocxl_hw.h | 1 +
2 files changed, 201 insertions(+)
diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 6472210..59e9003 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -12,13 +12,144 @@
* 2 of the License, or (at your option) any later version.
*/
+#include
#include
+#include
+#include
#include
#include "backend.h"
#include "ocxl_hw.h"
+/*
+ * Pseudo-filesystem to allocate inodes.
+ */
+
+#define OCXLFLASH_FS_MAGIC 0x1697698f
+
+static int ocxlflash_fs_cnt;
+static struct vfsmount *ocxlflash_vfs_mount;
+
+static const struct dentry_operations ocxlflash_fs_dops = {
+ .d_dname= simple_dname,
+};
+
+/*
+ * ocxlflash_fs_mount() - mount the pseudo-filesystem
+ * @fs_type: File system type.
+ * @flags: Flags for the filesystem.
+ * @dev_name: Device name associated with the filesystem.
+ * @data: Data pointer.
+ *
+ * Return: pointer to the directory entry structure
+ */
+static struct dentry *ocxlflash_fs_mount(struct file_system_type *fs_type,
+int flags, const char *dev_name,
+void *data)
+{
+ return mount_pseudo(fs_type, "ocxlflash:", NULL, &ocxlflash_fs_dops,
+ OCXLFLASH_FS_MAGIC);
+}
+
+static struct file_system_type ocxlflash_fs_type = {
+ .name = "ocxlflash",
+ .owner = THIS_MODULE,
+ .mount = ocxlflash_fs_mount,
+ .kill_sb= kill_anon_super,
+};
+
+/*
+ * ocxlflash_release_mapping() - release the memory mapping
+ * @ctx: Context whose mapping is to be released.
+ */
+static void ocxlflash_release_mapping(struct ocxlflash_context *ctx)
+{
+ if (ctx->mapping)
+ simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+ ctx->mapping = NULL;
+}
+
+/*
+ * ocxlflash_getfile() - allocate pseudo filesystem, inode, and the file
+ * @dev: Generic device of the host.
+ * @name: Name of the pseudo filesystem.
+ * @fops: File operations.
+ * @priv: Private data.
+ * @flags: Flags for the file.
+ *
+ * Return: pointer to the file on success, ERR_PTR on failure
+ */
+static struct file *ocxlflash_getfile(struct device *dev, const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags)
+{
+ struct qstr this;
+ struct path path;
+ struct file *file;
+ struct inode *inode = NULL;
+ int rc;
+
+ if (fops->owner && !try_module_get(fops->owner)) {
+ dev_err(dev, "%s: Owner does not exist\n", __func__);
+ rc = -ENOENT;
+ goto err1;
+ }
+
+ rc = simple_pin_fs(&ocxlflash_fs_type, &ocxlflash_vfs_mount,
+ &ocxlflash_fs_cnt);
+ if (unlikely(rc < 0)) {
+ dev_err(dev, "%s: Cannot mount ocxlflash pseudofs rc=%d\n",
+ __func__, rc);
+ goto err2;
+ }
+
+ inode = alloc_anon_inode(ocxlflash_vfs_mount->mnt_sb);
+ if (IS_ERR(inode)) {
+ rc = PTR_ERR(inode);
+ dev_err(dev, "%s: alloc_anon_inode failed rc=%d\n",
+ __func__, rc);
+ goto err3;
+ }
+
+ this.name = name;
+ this.len = strlen(name);
+ this.hash = 0;
+ path.dentry = d_alloc_pseudo(ocxlflash_vfs_mount->mnt_sb, &this);
+ if (!path.dentry) {
+ dev_err(dev, "%s: d_alloc_pseudo failed\n", __func__);
+ rc = -ENOMEM;
+ goto err4;
+ }
+
+ path.mnt = mntget(ocxlflash_vfs_mount);
+ d_instantiate(path.dentry, inode);
+
+ file = alloc_file(&path, OPEN_FMODE(flags), fops);
+ if (IS_ERR(file)) {
+ rc = PTR_ERR(file);
+ dev_err(dev, "%s: alloc_file failed rc=%d\n",
+ __func__, rc);
+ goto err5;
+ }
+
+ file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);
+ file->private_data = priv;
+out:
+ return file;
+err5:
+ path_put(&path);
+err4:
+ iput(inode);
+err3:
+ simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+err2:
+ module_put(fops->owner);
+err1:
+ file = ERR_PTR(rc);
+ goto ou
[PATCH v2 13/38] cxlflash: Support adapter file descriptors for OCXL
Allocate a file descriptor for an adapter context when requested. In order
to allocate inodes for the file descriptors, a pseudo filesystem is created
and used.
Signed-off-by: Uma Krishnan
Acked-by: Matthew R. Ochs
---
drivers/scsi/cxlflash/ocxl_hw.c | 200
drivers/scsi/cxlflash/ocxl_hw.h | 1 +
2 files changed, 201 insertions(+)
diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 6472210..59e9003 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -12,13 +12,144 @@
* 2 of the License, or (at your option) any later version.
*/
+#include
#include
+#include
+#include
#include
#include "backend.h"
#include "ocxl_hw.h"
+/*
+ * Pseudo-filesystem to allocate inodes.
+ */
+
+#define OCXLFLASH_FS_MAGIC 0x1697698f
+
+static int ocxlflash_fs_cnt;
+static struct vfsmount *ocxlflash_vfs_mount;
+
+static const struct dentry_operations ocxlflash_fs_dops = {
+ .d_dname= simple_dname,
+};
+
+/*
+ * ocxlflash_fs_mount() - mount the pseudo-filesystem
+ * @fs_type: File system type.
+ * @flags: Flags for the filesystem.
+ * @dev_name: Device name associated with the filesystem.
+ * @data: Data pointer.
+ *
+ * Return: pointer to the directory entry structure
+ */
+static struct dentry *ocxlflash_fs_mount(struct file_system_type *fs_type,
+int flags, const char *dev_name,
+void *data)
+{
+ return mount_pseudo(fs_type, "ocxlflash:", NULL, &ocxlflash_fs_dops,
+ OCXLFLASH_FS_MAGIC);
+}
+
+static struct file_system_type ocxlflash_fs_type = {
+ .name = "ocxlflash",
+ .owner = THIS_MODULE,
+ .mount = ocxlflash_fs_mount,
+ .kill_sb= kill_anon_super,
+};
+
+/*
+ * ocxlflash_release_mapping() - release the memory mapping
+ * @ctx: Context whose mapping is to be released.
+ */
+static void ocxlflash_release_mapping(struct ocxlflash_context *ctx)
+{
+ if (ctx->mapping)
+ simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+ ctx->mapping = NULL;
+}
+
+/*
+ * ocxlflash_getfile() - allocate pseudo filesystem, inode, and the file
+ * @dev: Generic device of the host.
+ * @name: Name of the pseudo filesystem.
+ * @fops: File operations.
+ * @priv: Private data.
+ * @flags: Flags for the file.
+ *
+ * Return: pointer to the file on success, ERR_PTR on failure
+ */
+static struct file *ocxlflash_getfile(struct device *dev, const char *name,
+ const struct file_operations *fops,
+ void *priv, int flags)
+{
+ struct qstr this;
+ struct path path;
+ struct file *file;
+ struct inode *inode = NULL;
+ int rc;
+
+ if (fops->owner && !try_module_get(fops->owner)) {
+ dev_err(dev, "%s: Owner does not exist\n", __func__);
+ rc = -ENOENT;
+ goto err1;
+ }
+
+ rc = simple_pin_fs(&ocxlflash_fs_type, &ocxlflash_vfs_mount,
+ &ocxlflash_fs_cnt);
+ if (unlikely(rc < 0)) {
+ dev_err(dev, "%s: Cannot mount ocxlflash pseudofs rc=%d\n",
+ __func__, rc);
+ goto err2;
+ }
+
+ inode = alloc_anon_inode(ocxlflash_vfs_mount->mnt_sb);
+ if (IS_ERR(inode)) {
+ rc = PTR_ERR(inode);
+ dev_err(dev, "%s: alloc_anon_inode failed rc=%d\n",
+ __func__, rc);
+ goto err3;
+ }
+
+ this.name = name;
+ this.len = strlen(name);
+ this.hash = 0;
+ path.dentry = d_alloc_pseudo(ocxlflash_vfs_mount->mnt_sb, &this);
+ if (!path.dentry) {
+ dev_err(dev, "%s: d_alloc_pseudo failed\n", __func__);
+ rc = -ENOMEM;
+ goto err4;
+ }
+
+ path.mnt = mntget(ocxlflash_vfs_mount);
+ d_instantiate(path.dentry, inode);
+
+ file = alloc_file(&path, OPEN_FMODE(flags), fops);
+ if (IS_ERR(file)) {
+ rc = PTR_ERR(file);
+ dev_err(dev, "%s: alloc_file failed rc=%d\n",
+ __func__, rc);
+ goto err5;
+ }
+
+ file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);
+ file->private_data = priv;
+out:
+ return file;
+err5:
+ path_put(&path);
+err4:
+ iput(inode);
+err3:
+ simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+err2:
+ module_put(fops->owner);
+err1:
+ file = ERR_PTR(rc);
+ goto out;
+}
+
/**
* ocxlflash_set_master() - sets the context as master
* @ctx_cookie:Adapter context to set as master.
@@ -75,6 +206,7 @@ static void *ocxlflash_dev_context_init(struct pci_dev
*pdev, void *afu_cookie)
ctx->pe = rc;
ctx->master = false;
+
