[PATCH v3 0/2] block/export/fuse: Fix build failure on FreeBSD

[PATCH v3 0/2] block/export/fuse: Fix build failure on FreeBSD

[Philippe Mathieu-Daudé via]

Since v2:
- Rearrange if-else-if ladder first (Kevin)

Philippe Mathieu-Daudé (2):
  block/export/fuse: Rearrange if-else-if ladder in fuse_fallocate()
  block/export/fuse: Fix build failure on FreeBSD

 block/export/fuse.c | 45 +++++++++++++++++++++++++--------------------
 1 file changed, 25 insertions(+), 20 deletions(-)

-- 
2.34.1

[PATCH v3 1/2] block/export/fuse: Rearrange if-else-if ladder in fuse_fallocate()

[Philippe Mathieu-Daudé via]

In order to safely maintain a mixture of #ifdef'ry with if-else-if
ladder, rearrange the last statement (!mode) first. Since it is
mutually exclusive with the other conditions, checking it first
doesn't make any logical difference, but allows to add #ifdef'ry
around in a more cleanly way.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---

One minor checkpatch error:

 ERROR: else should follow close brace '}'
 #29: FILE: block/export/fuse.c:651:
 +    }
 +    else if (mode & FALLOC_FL_PUNCH_HOLE) {
---
 block/export/fuse.c | 41 +++++++++++++++++++++--------------------
 1 file changed, 21 insertions(+), 20 deletions(-)

diff --git a/block/export/fuse.c b/block/export/fuse.c
index 6710d8aed86..d25e478c0a2 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -629,7 +629,26 @@ static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
         length = MIN(length, blk_len - offset);
     }
 
-    if (mode & FALLOC_FL_PUNCH_HOLE) {
+    if (!mode) {
+        /* We can only fallocate at the EOF with a truncate */
+        if (offset < blk_len) {
+            fuse_reply_err(req, EOPNOTSUPP);
+            return;
+        }
+
+        if (offset > blk_len) {
+            /* No preallocation needed here */
+            ret = fuse_do_truncate(exp, offset, true, PREALLOC_MODE_OFF);
+            if (ret < 0) {
+                fuse_reply_err(req, -ret);
+                return;
+            }
+        }
+
+        ret = fuse_do_truncate(exp, offset + length, true,
+                               PREALLOC_MODE_FALLOC);
+    }
+    else if (mode & FALLOC_FL_PUNCH_HOLE) {
         if (!(mode & FALLOC_FL_KEEP_SIZE)) {
             fuse_reply_err(req, EINVAL);
             return;
@@ -665,25 +684,7 @@ static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
         } while (ret == 0 && length > 0);
     }
 #endif /* CONFIG_FALLOCATE_ZERO_RANGE */
-    else if (!mode) {
-        /* We can only fallocate at the EOF with a truncate */
-        if (offset < blk_len) {
-            fuse_reply_err(req, EOPNOTSUPP);
-            return;
-        }
-
-        if (offset > blk_len) {
-            /* No preallocation needed here */
-            ret = fuse_do_truncate(exp, offset, true, PREALLOC_MODE_OFF);
-            if (ret < 0) {
-                fuse_reply_err(req, -ret);
-                return;
-            }
-        }
-
-        ret = fuse_do_truncate(exp, offset + length, true,
-                               PREALLOC_MODE_FALLOC);
-    } else {
+    else {
         ret = -EOPNOTSUPP;
     }
 
-- 
2.34.1

[PATCH v3 2/2] block/export/fuse: Fix build failure on FreeBSD

[Philippe Mathieu-Daudé via]

When building on FreeBSD we get:

  [816/6851] Compiling C object libblockdev.fa.p/block_export_fuse.c.o
  ../block/export/fuse.c:628:16: error: use of undeclared identifier 'FALLOC_FL_KEEP_SIZE'
      if (mode & FALLOC_FL_KEEP_SIZE) {
                 ^
  ../block/export/fuse.c:651:16: error: use of undeclared identifier 'FALLOC_FL_PUNCH_HOLE'
      if (mode & FALLOC_FL_PUNCH_HOLE) {
                 ^
  ../block/export/fuse.c:652:22: error: use of undeclared identifier 'FALLOC_FL_KEEP_SIZE'
          if (!(mode & FALLOC_FL_KEEP_SIZE)) {
                       ^
  3 errors generated.
  FAILED: libblockdev.fa.p/block_export_fuse.c.o

Meson indeed reported FALLOC_FL_PUNCH_HOLE is not available:

  C compiler for the host machine: cc (clang 10.0.1 "FreeBSD clang version 10.0.1")
  Checking for function "fallocate" : NO
  Checking for function "posix_fallocate" : YES
  Header <linux/falloc.h> has symbol "FALLOC_FL_PUNCH_HOLE" : NO
  Header <linux/falloc.h> has symbol "FALLOC_FL_ZERO_RANGE" : NO
  ...

Similarly to commit 304332039 ("block/export/fuse.c: fix musl build"),
guard the code requiring FALLOC_FL_KEEP_SIZE / FALLOC_FL_PUNCH_HOLE
definitions under CONFIG_FALLOCATE_PUNCH_HOLE #ifdef'ry.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 block/export/fuse.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/block/export/fuse.c b/block/export/fuse.c
index d25e478c0a2..fdda8e3c818 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -625,9 +625,11 @@ static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
         return;
     }
 
+#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
     if (mode & FALLOC_FL_KEEP_SIZE) {
         length = MIN(length, blk_len - offset);
     }
+#endif /* CONFIG_FALLOCATE_PUNCH_HOLE */
 
     if (!mode) {
         /* We can only fallocate at the EOF with a truncate */
@@ -648,6 +650,7 @@ static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
         ret = fuse_do_truncate(exp, offset + length, true,
                                PREALLOC_MODE_FALLOC);
     }
+#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
     else if (mode & FALLOC_FL_PUNCH_HOLE) {
         if (!(mode & FALLOC_FL_KEEP_SIZE)) {
             fuse_reply_err(req, EINVAL);
@@ -662,6 +665,7 @@ static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
             length -= size;
         } while (ret == 0 && length > 0);
     }
+#endif /* CONFIG_FALLOCATE_PUNCH_HOLE */
 #ifdef CONFIG_FALLOCATE_ZERO_RANGE
     else if (mode & FALLOC_FL_ZERO_RANGE) {
         if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + length > blk_len) {
-- 
2.34.1

Re: [PATCH v3 2/2] block/export/fuse: Fix build failure on FreeBSD

[Hanna Reitz]

On 01.02.22 12:26, Philippe Mathieu-Daudé wrote:
> When building on FreeBSD we get:
>
>    [816/6851] Compiling C object libblockdev.fa.p/block_export_fuse.c.o
>    ../block/export/fuse.c:628:16: error: use of undeclared identifier 'FALLOC_FL_KEEP_SIZE'
>        if (mode & FALLOC_FL_KEEP_SIZE) {
>                   ^
>    ../block/export/fuse.c:651:16: error: use of undeclared identifier 'FALLOC_FL_PUNCH_HOLE'
>        if (mode & FALLOC_FL_PUNCH_HOLE) {
>                   ^
>    ../block/export/fuse.c:652:22: error: use of undeclared identifier 'FALLOC_FL_KEEP_SIZE'
>            if (!(mode & FALLOC_FL_KEEP_SIZE)) {
>                         ^
>    3 errors generated.
>    FAILED: libblockdev.fa.p/block_export_fuse.c.o
>
> Meson indeed reported FALLOC_FL_PUNCH_HOLE is not available:
>
>    C compiler for the host machine: cc (clang 10.0.1 "FreeBSD clang version 10.0.1")
>    Checking for function "fallocate" : NO
>    Checking for function "posix_fallocate" : YES
>    Header <linux/falloc.h> has symbol "FALLOC_FL_PUNCH_HOLE" : NO
>    Header <linux/falloc.h> has symbol "FALLOC_FL_ZERO_RANGE" : NO
>    ...
>
> Similarly to commit 304332039 ("block/export/fuse.c: fix musl build"),
> guard the code requiring FALLOC_FL_KEEP_SIZE / FALLOC_FL_PUNCH_HOLE
> definitions under CONFIG_FALLOCATE_PUNCH_HOLE #ifdef'ry.
>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>   block/export/fuse.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/block/export/fuse.c b/block/export/fuse.c
> index d25e478c0a2..fdda8e3c818 100644
> --- a/block/export/fuse.c
> +++ b/block/export/fuse.c
> @@ -625,9 +625,11 @@ static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
>           return;
>       }
>   
> +#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
>       if (mode & FALLOC_FL_KEEP_SIZE) {
>           length = MIN(length, blk_len - offset);
>       }
> +#endif /* CONFIG_FALLOCATE_PUNCH_HOLE */
>   
>       if (!mode) {
>           /* We can only fallocate at the EOF with a truncate */
> @@ -648,6 +650,7 @@ static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
>           ret = fuse_do_truncate(exp, offset + length, true,
>                                  PREALLOC_MODE_FALLOC);
>       }
> +#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
>       else if (mode & FALLOC_FL_PUNCH_HOLE) {
>           if (!(mode & FALLOC_FL_KEEP_SIZE)) {
>               fuse_reply_err(req, EINVAL);
> @@ -662,6 +665,7 @@ static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
>               length -= size;
>           } while (ret == 0 && length > 0);
>       }
> +#endif /* CONFIG_FALLOCATE_PUNCH_HOLE */
>   #ifdef CONFIG_FALLOCATE_ZERO_RANGE
>       else if (mode & FALLOC_FL_ZERO_RANGE) {
>           if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + length > blk_len) {

I believe CONFIG_FALLOCATE_ZERO_RANGE only guarantees the presence of 
FALLOC_FL_ZERO_RANGE, so we probably should check for 
CONFIG_FALLOCATE_PUNCH_HOLE, too, here.

(Maybe in practice FALLOC_FL_ZERO_RANGE guarantees that 
FALLOC_FL_KEEP_SIZE exists, too, but then a check just wouldn’t hurt.)

Hanna

Re: [PATCH v3 0/2] block/export/fuse: Fix build failure on FreeBSD

[Kevin Wolf]

Am 01.02.2022 um 12:26 hat Philippe Mathieu-Daudé geschrieben:
> Since v2:
> - Rearrange if-else-if ladder first (Kevin)
> 
> Philippe Mathieu-Daudé (2):
>   block/export/fuse: Rearrange if-else-if ladder in fuse_fallocate()
>   block/export/fuse: Fix build failure on FreeBSD

Thanks, applied to the block branch.

Kevin