drivers/char/ipmi/kcs_bmc_cdev_ipmi.c
Source file repositories/reference/linux-study-clean/drivers/char/ipmi/kcs_bmc_cdev_ipmi.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/char/ipmi/kcs_bmc_cdev_ipmi.c- Extension
.c- Size
- 13583 bytes
- Lines
- 569
- Domain
- Driver Families
- Bucket
- drivers/char
- Inferred role
- Driver Families: operation-table or driver-model contract
- Status
- pattern implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
- Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Touches IRQ or DMA behavior; this matters for the representative real-device path.
- Allocates kernel memory; connect allocation flags and lifetime to context constraints.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/errno.hlinux/io.hlinux/ipmi_bmc.hlinux/list.hlinux/miscdevice.hlinux/module.hlinux/mutex.hlinux/platform_device.hlinux/poll.hlinux/sched.hlinux/slab.hkcs_bmc_client.h
Detected Declarations
struct kcs_bmc_ipmienum kcs_ipmi_phasesenum kcs_ipmi_errorsenum kcs_statesfunction set_statefunction kcs_bmc_ipmi_force_abortfunction kcs_bmc_ipmi_handle_datafunction kcs_bmc_ipmi_handle_cmdfunction kcs_bmc_ipmi_eventfunction kcs_bmc_ipmi_openfunction kcs_bmc_ipmi_pollfunction kcs_bmc_ipmi_readfunction kcs_bmc_ipmi_writefunction kcs_bmc_ipmi_ioctlfunction kcs_bmc_ipmi_releasefunction kcs_bmc_ipmi_add_devicefunction kcs_bmc_ipmi_remove_devicefunction kcs_bmc_ipmi_initfunction kcs_bmc_ipmi_exitmodule init kcs_bmc_ipmi_init
Annotated Snippet
static const struct file_operations kcs_bmc_ipmi_fops = {
.owner = THIS_MODULE,
.open = kcs_bmc_ipmi_open,
.read = kcs_bmc_ipmi_read,
.write = kcs_bmc_ipmi_write,
.release = kcs_bmc_ipmi_release,
.poll = kcs_bmc_ipmi_poll,
.unlocked_ioctl = kcs_bmc_ipmi_ioctl,
};
static DEFINE_SPINLOCK(kcs_bmc_ipmi_instances_lock);
static LIST_HEAD(kcs_bmc_ipmi_instances);
static int kcs_bmc_ipmi_add_device(struct kcs_bmc_device *kcs_bmc)
{
struct kcs_bmc_ipmi *priv;
int rc;
priv = devm_kzalloc(kcs_bmc->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
spin_lock_init(&priv->lock);
mutex_init(&priv->mutex);
init_waitqueue_head(&priv->queue);
priv->client.dev = kcs_bmc;
priv->client.ops = &kcs_bmc_ipmi_client_ops;
priv->data_in = devm_kmalloc(kcs_bmc->dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
priv->data_out = devm_kmalloc(kcs_bmc->dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
priv->kbuffer = devm_kmalloc(kcs_bmc->dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
priv->miscdev.minor = MISC_DYNAMIC_MINOR;
priv->miscdev.name = devm_kasprintf(kcs_bmc->dev, GFP_KERNEL, "%s%u", DEVICE_NAME,
kcs_bmc->channel);
if (!priv->data_in || !priv->data_out || !priv->kbuffer || !priv->miscdev.name)
return -EINVAL;
priv->miscdev.fops = &kcs_bmc_ipmi_fops;
rc = misc_register(&priv->miscdev);
if (rc) {
dev_err(kcs_bmc->dev, "Unable to register device: %d\n", rc);
return rc;
}
spin_lock_irq(&kcs_bmc_ipmi_instances_lock);
list_add(&priv->entry, &kcs_bmc_ipmi_instances);
spin_unlock_irq(&kcs_bmc_ipmi_instances_lock);
dev_info(kcs_bmc->dev, "Initialised IPMI client for channel %d", kcs_bmc->channel);
return 0;
}
static int kcs_bmc_ipmi_remove_device(struct kcs_bmc_device *kcs_bmc)
{
struct kcs_bmc_ipmi *priv = NULL, *pos;
spin_lock_irq(&kcs_bmc_ipmi_instances_lock);
list_for_each_entry(pos, &kcs_bmc_ipmi_instances, entry) {
if (pos->client.dev == kcs_bmc) {
priv = pos;
list_del(&pos->entry);
break;
}
}
spin_unlock_irq(&kcs_bmc_ipmi_instances_lock);
if (!priv)
return -ENODEV;
misc_deregister(&priv->miscdev);
kcs_bmc_disable_device(priv->client.dev, &priv->client);
devm_kfree(kcs_bmc->dev, priv->kbuffer);
devm_kfree(kcs_bmc->dev, priv->data_out);
devm_kfree(kcs_bmc->dev, priv->data_in);
devm_kfree(kcs_bmc->dev, priv);
return 0;
}
static const struct kcs_bmc_driver_ops kcs_bmc_ipmi_driver_ops = {
.add_device = kcs_bmc_ipmi_add_device,
.remove_device = kcs_bmc_ipmi_remove_device,
};
static struct kcs_bmc_driver kcs_bmc_ipmi_driver = {
.ops = &kcs_bmc_ipmi_driver_ops,
Annotation
- Immediate include surface: `linux/errno.h`, `linux/io.h`, `linux/ipmi_bmc.h`, `linux/list.h`, `linux/miscdevice.h`, `linux/module.h`, `linux/mutex.h`, `linux/platform_device.h`.
- Detected declarations: `struct kcs_bmc_ipmi`, `enum kcs_ipmi_phases`, `enum kcs_ipmi_errors`, `enum kcs_states`, `function set_state`, `function kcs_bmc_ipmi_force_abort`, `function kcs_bmc_ipmi_handle_data`, `function kcs_bmc_ipmi_handle_cmd`, `function kcs_bmc_ipmi_event`, `function kcs_bmc_ipmi_open`.
- Atlas domain: Driver Families / drivers/char.
- Implementation status: pattern implementation candidate.
- This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
- IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.