virtio_blk: set the zone write granularitygrafted

virtblk_read_zoned_limits() reads the write granularity that the device
reports in virtio_blk_zoned_characteristics and assigns it to the
physical block size and to io_min, but never to the limit that is named
after it. queue_limits.zone_write_granularity is left at zero, so
blk_validate_zoned_limits() raises it to the logical block size:

	if (lim->zone_write_granularity < lim->logical_block_size)
		lim->zone_write_granularity = lim->logical_block_size;

A device that reports a granularity coarser than its logical block size,
which is what the field exists to express, therefore has it silently
reduced. A 512e host managed disk passed through to a guest reports a
logical block size of 512 and a write granularity of 4096, and the guest
ends up with a zone write granularity of 512.

bio_split_alignment() returns lim->zone_write_granularity if it is non-zero
and bio_split_io_at() may split a bio with as per bio_split_alignment().
This can real to the write getting rejected by the host drive, as the write
is not aligned to the physical block size.

zonefs also takes its block size from bdev_zone_write_granularity(), so it
would incorrectly use 512 on a disk that requires 4096.

sd_zbc_read_zones() sets the limit from the physical block size for the
same reason. NVMe ZNS and null_blk leave it unset, but the fallback
gives the right answer for them, as their write granularity is the
logical block size. virtio carries a separate value that may exceed it.

Set the zone write granularity from the value that the device reports.

Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices")
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Link: https://patch.msgid.link/20260918140641.2031075-2-cassel@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 438 insertions, 0 deletions

diff --git a/fs/coda/psdev.c b/fs/coda/psdev.c
new file mode 100644
index 000000000..3c3148588
--- /dev/null
+++ b/fs/coda/psdev.c
@@ -0,0 +1,438 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      	An implementation of a loadable kernel mode driver providing
+ *		multiple kernel/user space bidirectional communications links.
+ *
+ * 		Author: 	Alan Cox <alan@lxorguk.ukuu.org.uk>
+ * 
+ *              Adapted to become the Linux 2.0 Coda pseudo device
+ *              Peter  Braam  <braam@maths.ox.ac.uk> 
+ *              Michael Callahan <mjc@emmy.smith.edu>           
+ *
+ *              Changes for Linux 2.1
+ *              Copyright (c) 1997 Carnegie-Mellon University
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/time.h>
+#include <linux/sched/signal.h>
+#include <linux/slab.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/delay.h>
+#include <linux/skbuff.h>
+#include <linux/proc_fs.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/device.h>
+#include <linux/pid_namespace.h>
+#include <asm/io.h>
+#include <linux/uaccess.h>
+
+#include <linux/coda.h>
+#include "coda_psdev.h"
+#include "coda_linux.h"
+
+#include "coda_int.h"
+
+/* statistics */
+int           coda_hard;         /* allows signals during upcalls */
+unsigned long coda_timeout = 30; /* .. secs, then signals will dequeue */
+
+
+struct venus_comm coda_comms[MAX_CODADEVS];
+static struct class *coda_psdev_class;
+
+/*
+ * Device operations
+ */
+
+static __poll_t coda_psdev_poll(struct file *file, poll_table * wait)
+{
+        struct venus_comm *vcp = (struct venus_comm *) file->private_data;
+	__poll_t mask = EPOLLOUT | EPOLLWRNORM;
+
+	poll_wait(file, &vcp->vc_waitq, wait);
+	mutex_lock(&vcp->vc_mutex);
+	if (!list_empty(&vcp->vc_pending))
+                mask |= EPOLLIN | EPOLLRDNORM;
+	mutex_unlock(&vcp->vc_mutex);
+
+	return mask;
+}
+
+static long coda_psdev_ioctl(struct file * filp, unsigned int cmd, unsigned long arg)
+{
+	unsigned int data;
+
+	switch(cmd) {
+	case CIOC_KERNEL_VERSION:
+		data = CODA_KERNEL_VERSION;
+		return put_user(data, (int __user *) arg);
+	default:
+		return -ENOTTY;
+	}
+
+	return 0;
+}
+
+/*
+ *	Receive a message written by Venus to the psdev
+ */
+ 
+static ssize_t coda_psdev_write(struct file *file, const char __user *buf, 
+				size_t nbytes, loff_t *off)
+{
+        struct venus_comm *vcp = (struct venus_comm *) file->private_data;
+        struct upc_req *req = NULL;
+        struct upc_req *tmp;
+	struct list_head *lh;
+	struct coda_in_hdr hdr;
+	ssize_t retval = 0, count = 0;
+	int error;
+
+	/* make sure there is enough to copy out the (opcode, unique) values */
+	if (nbytes < (2 * sizeof(u_int32_t)))
+		return -EINVAL;
+
+        /* Peek at the opcode, uniquefier */
+	if (copy_from_user(&hdr, buf, 2 * sizeof(u_int32_t)))
+	        return -EFAULT;
+
+        if (DOWNCALL(hdr.opcode)) {
+		union outputArgs *dcbuf;
+		int size = sizeof(*dcbuf);
+
+		if  ( nbytes < sizeof(struct coda_out_hdr) ) {
+			pr_warn("coda_downcall opc %d uniq %d, not enough!\n",
+				hdr.opcode, hdr.unique);
+			count = nbytes;
+			goto out;
+		}
+		if ( nbytes > size ) {
+			pr_warn("downcall opc %d, uniq %d, too much!",
+				hdr.opcode, hdr.unique);
+		        nbytes = size;
+		}
+
+		dcbuf = vmemdup_user(buf, nbytes);
+		if (IS_ERR(dcbuf)) {
+			retval = PTR_ERR(dcbuf);
+			goto out;
+		}
+
+		/* what downcall errors does Venus handle ? */
+		error = coda_downcall(vcp, hdr.opcode, dcbuf, nbytes);
+
+		kvfree(dcbuf);
+		if (error) {
+			pr_warn("%s: coda_downcall error: %d\n",
+				__func__, error);
+			retval = error;
+			goto out;
+		}
+		count = nbytes;
+		goto out;
+	}
+        
+	/* Look for the message on the processing queue. */
+	mutex_lock(&vcp->vc_mutex);
+	list_for_each(lh, &vcp->vc_processing) {
+		tmp = list_entry(lh, struct upc_req , uc_chain);
+		if (tmp->uc_unique == hdr.unique) {
+			req = tmp;
+			list_del(&req->uc_chain);
+			break;
+		}
+	}
+	mutex_unlock(&vcp->vc_mutex);
+
+	if (!req) {
+		pr_warn("%s: msg (%d, %d) not found\n",
+			__func__, hdr.opcode, hdr.unique);
+		retval = -ESRCH;
+		goto out;
+	}
+
+        /* move data into response buffer. */
+	if (req->uc_outSize < nbytes) {
+		pr_warn("%s: too much cnt: %d, cnt: %ld, opc: %d, uniq: %d.\n",
+			__func__, req->uc_outSize, (long)nbytes,
+			hdr.opcode, hdr.unique);
+		nbytes = req->uc_outSize; /* don't have more space! */
+	}
+        if (copy_from_user(req->uc_data, buf, nbytes)) {
+		req->uc_flags |= CODA_REQ_ABORT;
+		wake_up(&req->uc_sleep);
+		retval = -EFAULT;
+		goto out;
+	}
+
+	/* adjust outsize. is this useful ?? */
+	req->uc_outSize = nbytes;
+	req->uc_flags |= CODA_REQ_WRITE;
+	count = nbytes;
+
+	/* Convert filedescriptor into a file handle */
+	if (req->uc_opcode == CODA_OPEN_BY_FD) {
+		struct coda_open_by_fd_out *outp =
+			(struct coda_open_by_fd_out *)req->uc_data;
+		if (!outp->oh.result) {
+			outp->fh = fget(outp->fd);
+			if (!outp->fh)
+				return -EBADF;
+		}
+	}
+
+        wake_up(&req->uc_sleep);
+out:
+        return(count ? count : retval);  
+}
+
+/*
+ *	Read a message from the kernel to Venus
+ */
+
+static ssize_t coda_psdev_read(struct file * file, char __user * buf, 
+			       size_t nbytes, loff_t *off)
+{
+	DECLARE_WAITQUEUE(wait, current);
+        struct venus_comm *vcp = (struct venus_comm *) file->private_data;
+        struct upc_req *req;
+	ssize_t retval = 0, count = 0;
+
+	if (nbytes == 0)
+		return 0;
+
+	mutex_lock(&vcp->vc_mutex);
+
+	add_wait_queue(&vcp->vc_waitq, &wait);
+	set_current_state(TASK_INTERRUPTIBLE);
+
+	while (list_empty(&vcp->vc_pending)) {
+		if (file->f_flags & O_NONBLOCK) {
+			retval = -EAGAIN;
+			break;
+		}
+		if (signal_pending(current)) {
+			retval = -ERESTARTSYS;
+			break;
+		}
+		mutex_unlock(&vcp->vc_mutex);
+		schedule();
+		mutex_lock(&vcp->vc_mutex);
+	}
+
+	set_current_state(TASK_RUNNING);
+	remove_wait_queue(&vcp->vc_waitq, &wait);
+
+	if (retval)
+		goto out;
+
+	req = list_entry(vcp->vc_pending.next, struct upc_req,uc_chain);
+	list_del(&req->uc_chain);
+
+	/* Move the input args into userspace */
+	count = req->uc_inSize;
+	if (nbytes < req->uc_inSize) {
+		pr_warn("%s: Venus read %ld bytes of %d in message\n",
+			__func__, (long)nbytes, req->uc_inSize);
+		count = nbytes;
+        }
+
+	if (copy_to_user(buf, req->uc_data, count))
+	        retval = -EFAULT;
+        
+	/* If request was not a signal, enqueue and don't free */
+	if (!(req->uc_flags & CODA_REQ_ASYNC)) {
+		req->uc_flags |= CODA_REQ_READ;
+		list_add_tail(&(req->uc_chain), &vcp->vc_processing);
+		goto out;
+	}
+
+	kvfree(req->uc_data);
+	kfree(req);
+out:
+	mutex_unlock(&vcp->vc_mutex);
+	return (count ? count : retval);
+}
+
+static int coda_psdev_open(struct inode * inode, struct file * file)
+{
+	struct venus_comm *vcp;
+	int idx, err;
+
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
+	if (current_user_ns() != &init_user_ns)
+		return -EINVAL;
+
+	idx = iminor(inode);
+	if (idx < 0 || idx >= MAX_CODADEVS)
+		return -ENODEV;
+
+	err = -EBUSY;
+	vcp = &coda_comms[idx];
+	mutex_lock(&vcp->vc_mutex);
+
+	if (!vcp->vc_inuse) {
+		vcp->vc_inuse++;
+
+		INIT_LIST_HEAD(&vcp->vc_pending);
+		INIT_LIST_HEAD(&vcp->vc_processing);
+		init_waitqueue_head(&vcp->vc_waitq);
+		vcp->vc_sb = NULL;
+		vcp->vc_seq = 0;
+
+		file->private_data = vcp;
+		err = 0;
+	}
+
+	mutex_unlock(&vcp->vc_mutex);
+	return err;
+}
+
+
+static int coda_psdev_release(struct inode * inode, struct file * file)
+{
+	struct venus_comm *vcp = (struct venus_comm *) file->private_data;
+	struct upc_req *req, *tmp;
+
+	if (!vcp || !vcp->vc_inuse ) {
+		pr_warn("%s: Not open.\n", __func__);
+		return -1;
+	}
+
+	mutex_lock(&vcp->vc_mutex);
+
+	/* Wakeup clients so they can return. */
+	list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) {
+		list_del(&req->uc_chain);
+
+		/* Async requests need to be freed here */
+		if (req->uc_flags & CODA_REQ_ASYNC) {
+			kvfree(req->uc_data);
+			kfree(req);
+			continue;
+		}
+		req->uc_flags |= CODA_REQ_ABORT;
+		wake_up(&req->uc_sleep);
+	}
+
+	list_for_each_entry_safe(req, tmp, &vcp->vc_processing, uc_chain) {
+		list_del(&req->uc_chain);
+
+		req->uc_flags |= CODA_REQ_ABORT;
+		wake_up(&req->uc_sleep);
+	}
+
+	file->private_data = NULL;
+	vcp->vc_inuse--;
+	mutex_unlock(&vcp->vc_mutex);
+	return 0;
+}
+
+
+static const struct file_operations coda_psdev_fops = {
+	.owner		= THIS_MODULE,
+	.read		= coda_psdev_read,
+	.write		= coda_psdev_write,
+	.poll		= coda_psdev_poll,
+	.unlocked_ioctl	= coda_psdev_ioctl,
+	.open		= coda_psdev_open,
+	.release	= coda_psdev_release,
+	.llseek		= noop_llseek,
+};
+
+static int __init init_coda_psdev(void)
+{
+	int i, err = 0;
+	if (register_chrdev(CODA_PSDEV_MAJOR, "coda", &coda_psdev_fops)) {
+		pr_err("%s: unable to get major %d\n",
+		       __func__, CODA_PSDEV_MAJOR);
+		return -EIO;
+	}
+	coda_psdev_class = class_create("coda");
+	if (IS_ERR(coda_psdev_class)) {
+		err = PTR_ERR(coda_psdev_class);
+		goto out_chrdev;
+	}		
+	for (i = 0; i < MAX_CODADEVS; i++) {
+		mutex_init(&(&coda_comms[i])->vc_mutex);
+		device_create(coda_psdev_class, NULL,
+			      MKDEV(CODA_PSDEV_MAJOR, i), NULL, "cfs%d", i);
+	}
+	coda_sysctl_init();
+	goto out;
+
+out_chrdev:
+	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
+out:
+	return err;
+}
+
+MODULE_AUTHOR("Jan Harkes, Peter J. Braam");
+MODULE_DESCRIPTION("Coda Distributed File System VFS interface");
+MODULE_ALIAS_CHARDEV_MAJOR(CODA_PSDEV_MAJOR);
+MODULE_LICENSE("GPL");
+MODULE_VERSION("7.2");
+
+static int __init init_coda(void)
+{
+	int status;
+	int i;
+
+	status = coda_init_inodecache();
+	if (status)
+		goto out2;
+	status = init_coda_psdev();
+	if ( status ) {
+		pr_warn("Problem (%d) in init_coda_psdev\n", status);
+		goto out1;
+	}
+	
+	status = register_filesystem(&coda_fs_type);
+	if (status) {
+		pr_warn("failed to register filesystem!\n");
+		goto out;
+	}
+	return 0;
+out:
+	for (i = 0; i < MAX_CODADEVS; i++)
+		device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
+	class_destroy(coda_psdev_class);
+	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
+	coda_sysctl_clean();
+out1:
+	coda_destroy_inodecache();
+out2:
+	return status;
+}
+
+static void __exit exit_coda(void)
+{
+        int err, i;
+
+	err = unregister_filesystem(&coda_fs_type);
+	if (err != 0)
+		pr_warn("failed to unregister filesystem\n");
+	for (i = 0; i < MAX_CODADEVS; i++)
+		device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
+	class_destroy(coda_psdev_class);
+	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
+	coda_sysctl_clean();
+	coda_destroy_inodecache();
+}
+
+module_init(init_coda);
+module_exit(exit_coda);
+