From c5905b2cb754423d31cdb8adc625639aa7f8acc6 Mon Sep 17 00:00:00 2001
From: Andrew Walker <andrew.walker@truenas.com>
Date: Fri, 6 Mar 2026 13:05:58 -0600
Subject: [PATCH] Implement lzc_send_progress

This commit adds an implementation of lzc_send_progress, which
existed in the libzfs_core header, but not in ABI and lacked
an actual implementation. The libzfs_send_progress function
is altered so that it wraps around the lzc operation. This
fills a functional gap in libzfs core.

Reviewed-by: Alexander Motin <alexander.motin@TrueNAS.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Signed-off-by: Andrew Walker <andrew.walker@truenas.com>
Closes #18288
---
 include/libzfs_core.h           |  2 +-
 lib/libzfs/libzfs_sendrecv.c    | 17 ++---------------
 lib/libzfs_core/libzfs_core.abi |  8 ++++++++
 lib/libzfs_core/libzfs_core.c   | 33 +++++++++++++++++++++++++++++++++
 4 files changed, 44 insertions(+), 16 deletions(-)

diff --git a/include/libzfs_core.h b/include/libzfs_core.h
index 231beaa69..deb810230 100644
--- a/include/libzfs_core.h
+++ b/include/libzfs_core.h
@@ -125,7 +125,7 @@ _LIBZFS_CORE_H int lzc_send_space(const char *, const char *,
 _LIBZFS_CORE_H int lzc_send_space_resume_redacted(const char *, const char *,
     enum lzc_send_flags, uint64_t, uint64_t, uint64_t, const char *,
     int, uint64_t *);
-_LIBZFS_CORE_H uint64_t lzc_send_progress(int);
+_LIBZFS_CORE_H int lzc_send_progress(const char *, int, uint64_t *, uint64_t *);
 
 _LIBZFS_CORE_H boolean_t lzc_exists(const char *);
 
diff --git a/lib/libzfs/libzfs_sendrecv.c b/lib/libzfs/libzfs_sendrecv.c
index 9d693223e..e2b351293 100644
--- a/lib/libzfs/libzfs_sendrecv.c
+++ b/lib/libzfs/libzfs_sendrecv.c
@@ -927,21 +927,8 @@ int
 zfs_send_progress(zfs_handle_t *zhp, int fd, uint64_t *bytes_written,
     uint64_t *blocks_visited)
 {
-	zfs_cmd_t zc = {"\0"};
-
-	if (bytes_written != NULL)
-		*bytes_written = 0;
-	if (blocks_visited != NULL)
-		*blocks_visited = 0;
-	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
-	zc.zc_cookie = fd;
-	if (zfs_ioctl(zhp->zfs_hdl, ZFS_IOC_SEND_PROGRESS, &zc) != 0)
-		return (errno);
-	if (bytes_written != NULL)
-		*bytes_written = zc.zc_cookie;
-	if (blocks_visited != NULL)
-		*blocks_visited = zc.zc_objset_type;
-	return (0);
+	return (lzc_send_progress(zhp->zfs_name, fd, bytes_written,
+	    blocks_visited));
 }
 
 static volatile boolean_t send_progress_thread_signal_duetotimer;
diff --git a/lib/libzfs_core/libzfs_core.abi b/lib/libzfs_core/libzfs_core.abi
index 1cfd2a81d..5c5d29243 100644
--- a/lib/libzfs_core/libzfs_core.abi
+++ b/lib/libzfs_core/libzfs_core.abi
@@ -227,6 +227,7 @@
     <elf-symbol name='lzc_send_redacted' type='func-type' binding='global-binding' visibility='default-visibility' is-defined='yes'/>
     <elf-symbol name='lzc_send_resume' type='func-type' binding='global-binding' visibility='default-visibility' is-defined='yes'/>
     <elf-symbol name='lzc_send_resume_redacted' type='func-type' binding='global-binding' visibility='default-visibility' is-defined='yes'/>
+    <elf-symbol name='lzc_send_progress' type='func-type' binding='global-binding' visibility='default-visibility' is-defined='yes'/>
     <elf-symbol name='lzc_send_space' type='func-type' binding='global-binding' visibility='default-visibility' is-defined='yes'/>
     <elf-symbol name='lzc_send_space_resume_redacted' type='func-type' binding='global-binding' visibility='default-visibility' is-defined='yes'/>
     <elf-symbol name='lzc_send_wrapper' type='func-type' binding='global-binding' visibility='default-visibility' is-defined='yes'/>
@@ -3997,6 +3998,13 @@
       <parameter type-id='5d6479ae' name='spacep'/>
       <return type-id='95e97e5e'/>
     </function-decl>
+    <function-decl name='lzc_send_progress' mangled-name='lzc_send_progress' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='lzc_send_progress'>
+      <parameter type-id='80f4b756' name='snapname'/>
+      <parameter type-id='95e97e5e' name='fd'/>
+      <parameter type-id='5d6479ae' name='bytes_written'/>
+      <parameter type-id='5d6479ae' name='blocks_visited'/>
+      <return type-id='95e97e5e'/>
+    </function-decl>
     <function-decl name='lzc_send_space' mangled-name='lzc_send_space' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='lzc_send_space'>
       <parameter type-id='80f4b756' name='snapname'/>
       <parameter type-id='80f4b756' name='from'/>
diff --git a/lib/libzfs_core/libzfs_core.c b/lib/libzfs_core/libzfs_core.c
index 9347aa7c6..c6cd62e76 100644
--- a/lib/libzfs_core/libzfs_core.c
+++ b/lib/libzfs_core/libzfs_core.c
@@ -1016,6 +1016,39 @@ lzc_send_space(const char *snapname, const char *from,
 	    NULL, -1, spacep));
 }
 
+/*
+ * Query the progress of a send stream identified by the snapshot name and
+ * the file descriptor the stream is being written to.
+ *
+ * snapname    name of the snapshot being sent
+ * fd          file descriptor of the active send stream
+ * bytes_written  on success, set to the number of bytes sent so far
+ * blocks_visited on success, set to the number of logical blocks traversed
+ *
+ * Returns 0 on success.  Returns ENOENT if no send stream matching the
+ * snapshot name and file descriptor was found in the current process.
+ */
+int
+lzc_send_progress(const char *snapname, int fd, uint64_t *bytes_written,
+    uint64_t *blocks_visited)
+{
+	zfs_cmd_t zc = {"\0"};
+
+	if (bytes_written != NULL)
+		*bytes_written = 0;
+	if (blocks_visited != NULL)
+		*blocks_visited = 0;
+	(void) strlcpy(zc.zc_name, snapname, sizeof (zc.zc_name));
+	zc.zc_cookie = fd;
+	if (lzc_ioctl_fd(g_fd, ZFS_IOC_SEND_PROGRESS, &zc) != 0)
+		return (errno);
+	if (bytes_written != NULL)
+		*bytes_written = zc.zc_cookie;
+	if (blocks_visited != NULL)
+		*blocks_visited = zc.zc_objset_type;
+	return (0);
+}
+
 static int
 recv_read(int fd, void *buf, int ilen)
 {