[Qemu-devel] [RFC PATCH 15/41] block: Add permissions to blk_new()

[Kevin Wolf]

We want every user to be specific about the permissions it needs, so
we'll pass the initial permissions as parameters to blk_new(). A user
only needs to call blk_set_perm() if it wants to change the permissions
after the fact.

The permissions are stored in the BlockBackend and applied whenever a
BlockDriverState should be attached in blk_insert_bs().

This does not include actually choosing the right set of permissions
yet. Instead, the usual FIXME comment is added to each place and will be
addressed in individual patches.

Signed-off-by: Kevin Wolf <address@hidden>
---
 block/backup.c                   |  3 ++-
 block/block-backend.c            | 12 ++++++------
 block/commit.c                   | 12 ++++++++----
 block/mirror.c                   |  3 ++-
 blockdev.c                       |  2 +-
 blockjob.c                       |  3 ++-
 hmp.c                            |  3 ++-
 hw/block/fdc.c                   |  3 ++-
 hw/core/qdev-properties-system.c |  3 ++-
 hw/ide/qdev.c                    |  3 ++-
 hw/scsi/scsi-disk.c              |  3 ++-
 include/sysemu/block-backend.h   |  2 +-
 migration/block.c                |  3 ++-
 nbd/server.c                     |  3 ++-
 tests/test-blockjob.c            |  3 ++-
 tests/test-throttle.c            |  7 ++++---
 16 files changed, 42 insertions(+), 26 deletions(-)

diff --git a/block/backup.c b/block/backup.c
index ea38733..bb76c69 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -624,7 +624,8 @@ BlockJob *backup_job_create(const char *job_id, 
BlockDriverState *bs,
         goto error;
     }
 
-    job->target = blk_new();
+    /* FIXME Use real permissions */
+    job->target = blk_new(0, BLK_PERM_ALL);
     blk_insert_bs(job->target, target);
 
     job->on_source_error = on_source_error;
diff --git a/block/block-backend.c b/block/block-backend.c
index 8f0348d..a219f0b 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -123,14 +123,14 @@ static const BdrvChildRole child_root = {
  * Store an error through @errp on failure, unless it's null.
  * Return the new BlockBackend on success, null on failure.
  */
-BlockBackend *blk_new(void)
+BlockBackend *blk_new(uint64_t perm, uint64_t shared_perm)
 {
     BlockBackend *blk;
 
     blk = g_new0(BlockBackend, 1);
     blk->refcnt = 1;
-    blk->perm = 0;
-    blk->shared_perm = BLK_PERM_ALL;
+    blk->perm = perm;
+    blk->shared_perm = shared_perm;
     blk_set_enable_write_cache(blk, true);
 
     qemu_co_queue_init(&blk->public.throttled_reqs[0]);
@@ -161,7 +161,7 @@ BlockBackend *blk_new_open(const char *filename, const char 
*reference,
     BlockBackend *blk;
     BlockDriverState *bs;
 
-    blk = blk_new();
+    blk = blk_new(0, BLK_PERM_ALL);
     bs = bdrv_open(filename, reference, options, flags, errp);
     if (!bs) {
         blk_unref(blk);
@@ -505,9 +505,9 @@ void blk_remove_bs(BlockBackend *blk)
 void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs)
 {
     bdrv_ref(bs);
-    /* FIXME Use real permissions */
     blk->root = bdrv_root_attach_child(bs, "root", &child_root,
-                                       0, BLK_PERM_ALL, blk, &error_abort);
+                                       blk->perm, blk->shared_perm, blk,
+                                       &error_abort);
 
     notifier_list_notify(&blk->insert_bs_notifiers, blk);
     if (blk->public.throttle_state) {
diff --git a/block/commit.c b/block/commit.c
index c284e85..1897e98 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -275,10 +275,12 @@ void commit_start(const char *job_id, BlockDriverState 
*bs,
         block_job_add_bdrv(&s->common, overlay_bs);
     }
 
-    s->base = blk_new();
+    /* FIXME Use real permissions */
+    s->base = blk_new(0, BLK_PERM_ALL);
     blk_insert_bs(s->base, base);
 
-    s->top = blk_new();
+    /* FIXME Use real permissions */
+    s->top = blk_new(0, BLK_PERM_ALL);
     blk_insert_bs(s->top, top);
 
     s->active = bs;
@@ -328,10 +330,12 @@ int bdrv_commit(BlockDriverState *bs)
         }
     }
 
-    src = blk_new();
+    /* FIXME Use real permissions */
+    src = blk_new(0, BLK_PERM_ALL);
     blk_insert_bs(src, bs);
 
-    backing = blk_new();
+    /* FIXME Use real permissions */
+    backing = blk_new(0, BLK_PERM_ALL);
     blk_insert_bs(backing, bs->backing->bs);
 
     length = blk_getlength(src);
diff --git a/block/mirror.c b/block/mirror.c
index 301ba92..810933e 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -985,7 +985,8 @@ static void mirror_start_job(const char *job_id, 
BlockDriverState *bs,
         return;
     }
 
-    s->target = blk_new();
+    /* FIXME Use real permissions */
+    s->target = blk_new(0, BLK_PERM_ALL);
     blk_insert_bs(s->target, target);
 
     s->replaces = g_strdup(replaces);
diff --git a/blockdev.c b/blockdev.c
index db82ac9..2e195f1 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -554,7 +554,7 @@ static BlockBackend *blockdev_init(const char *file, QDict 
*bs_opts,
     if ((!file || !*file) && !qdict_size(bs_opts)) {
         BlockBackendRootState *blk_rs;
 
-        blk = blk_new();
+        blk = blk_new(0, BLK_PERM_ALL);
         blk_rs = blk_get_root_state(blk);
         blk_rs->open_flags    = bdrv_flags;
         blk_rs->read_only     = read_only;
diff --git a/blockjob.c b/blockjob.c
index abee11b..508e0e5 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -159,7 +159,8 @@ void *block_job_create(const char *job_id, const 
BlockJobDriver *driver,
         }
     }
 
-    blk = blk_new();
+    /* FIXME Use real permissions */
+    blk = blk_new(0, BLK_PERM_ALL);
     blk_insert_bs(blk, bs);
 
     job = g_malloc0(driver->instance_size);
diff --git a/hmp.c b/hmp.c
index 2bc4f06..15fd3f7 100644
--- a/hmp.c
+++ b/hmp.c
@@ -2044,7 +2044,8 @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict)
     if (!blk) {
         BlockDriverState *bs = bdrv_lookup_bs(NULL, device, &err);
         if (bs) {
-            blk = local_blk = blk_new();
+            /* FIXME Use real permissions */
+            blk = local_blk = blk_new(0, BLK_PERM_ALL);
             blk_insert_bs(blk, bs);
         } else {
             goto fail;
diff --git a/hw/block/fdc.c b/hw/block/fdc.c
index 17d29e7..74f3634 100644
--- a/hw/block/fdc.c
+++ b/hw/block/fdc.c
@@ -533,7 +533,8 @@ static int floppy_drive_init(DeviceState *qdev)
 
     if (!dev->conf.blk) {
         /* Anonymous BlockBackend for an empty drive */
-        dev->conf.blk = blk_new();
+        /* FIXME Use real permissions */
+        dev->conf.blk = blk_new(0, BLK_PERM_ALL);
         ret = blk_attach_dev(dev->conf.blk, qdev);
         assert(ret == 0);
     }
diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
index 94f4d8b..cca4775 100644
--- a/hw/core/qdev-properties-system.c
+++ b/hw/core/qdev-properties-system.c
@@ -78,7 +78,8 @@ static void parse_drive(DeviceState *dev, const char *str, 
void **ptr,
     if (!blk) {
         BlockDriverState *bs = bdrv_lookup_bs(NULL, str, NULL);
         if (bs) {
-            blk = blk_new();
+            /* FIXME Use real permissions */
+            blk = blk_new(0, BLK_PERM_ALL);
             blk_insert_bs(blk, bs);
             blk_created = true;
         }
diff --git a/hw/ide/qdev.c b/hw/ide/qdev.c
index dbaa75c..bb3c377 100644
--- a/hw/ide/qdev.c
+++ b/hw/ide/qdev.c
@@ -170,7 +170,8 @@ static int ide_dev_initfn(IDEDevice *dev, IDEDriveKind kind)
             return -1;
         } else {
             /* Anonymous BlockBackend for an empty drive */
-            dev->conf.blk = blk_new();
+            /* FIXME Use real permissions */
+            dev->conf.blk = blk_new(0, BLK_PERM_ALL);
         }
     }
 
diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
index cc06fe5..61c44a9 100644
--- a/hw/scsi/scsi-disk.c
+++ b/hw/scsi/scsi-disk.c
@@ -2365,7 +2365,8 @@ static void scsi_cd_realize(SCSIDevice *dev, Error **errp)
     SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, dev);
 
     if (!dev->conf.blk) {
-        dev->conf.blk = blk_new();
+        /* FIXME Use real permissions */
+        dev->conf.blk = blk_new(0, BLK_PERM_ALL);
     }
 
     s->qdev.blocksize = 2048;
diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h
index 4a5783a..1bda6d7 100644
--- a/include/sysemu/block-backend.h
+++ b/include/sysemu/block-backend.h
@@ -78,7 +78,7 @@ typedef struct BlockBackendPublic {
     QLIST_ENTRY(BlockBackendPublic) round_robin;
 } BlockBackendPublic;
 
-BlockBackend *blk_new(void);
+BlockBackend *blk_new(uint64_t perm, uint64_t shared_perm);
 BlockBackend *blk_new_open(const char *filename, const char *reference,
                            QDict *options, int flags, Error **errp);
 int blk_get_refcnt(BlockBackend *blk);
diff --git a/migration/block.c b/migration/block.c
index ebc10e6..6b7ffd4 100644
--- a/migration/block.c
+++ b/migration/block.c
@@ -415,7 +415,8 @@ static void init_blk_migration(QEMUFile *f)
         }
 
         bmds = g_new0(BlkMigDevState, 1);
-        bmds->blk = blk_new();
+        /* FIXME Use real permissions */
+        bmds->blk = blk_new(0, BLK_PERM_ALL);
         bmds->blk_name = g_strdup(bdrv_get_device_name(bs));
         bmds->bulk_completed = 0;
         bmds->total_sectors = sectors;
diff --git a/nbd/server.c b/nbd/server.c
index efe5cb8..871111c 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -890,7 +890,8 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t 
dev_offset, off_t size,
     BlockBackend *blk;
     NBDExport *exp = g_malloc0(sizeof(NBDExport));
 
-    blk = blk_new();
+    /* FIXME Use real permissions */
+    blk = blk_new(0, BLK_PERM_ALL);
     blk_insert_bs(blk, bs);
     blk_set_enable_write_cache(blk, !writethrough);
 
diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c
index 068c9e4..1dd1cfa 100644
--- a/tests/test-blockjob.c
+++ b/tests/test-blockjob.c
@@ -53,7 +53,8 @@ static BlockJob *do_test_id(BlockBackend *blk, const char *id,
  * BlockDriverState inserted. */
 static BlockBackend *create_blk(const char *name)
 {
-    BlockBackend *blk = blk_new();
+    /* FIXME Use real permissions */
+    BlockBackend *blk = blk_new(0, BLK_PERM_ALL);
     BlockDriverState *bs;
 
     bs = bdrv_open("null-co://", NULL, NULL, 0, &error_abort);
diff --git a/tests/test-throttle.c b/tests/test-throttle.c
index 363b59a..5846433 100644
--- a/tests/test-throttle.c
+++ b/tests/test-throttle.c
@@ -593,9 +593,10 @@ static void test_groups(void)
     BlockBackend *blk1, *blk2, *blk3;
     BlockBackendPublic *blkp1, *blkp2, *blkp3;
 
-    blk1 = blk_new();
-    blk2 = blk_new();
-    blk3 = blk_new();
+    /* FIXME Use real permissions */
+    blk1 = blk_new(0, BLK_PERM_ALL);
+    blk2 = blk_new(0, BLK_PERM_ALL);
+    blk3 = blk_new(0, BLK_PERM_ALL);
 
     blkp1 = blk_get_public(blk1);
     blkp2 = blk_get_public(blk2);
-- 
1.8.3.1