The branch main has been updated by khng:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=3703c18883341f3ff09c42d7f3b36ab80e4a071b

commit 3703c18883341f3ff09c42d7f3b36ab80e4a071b
Author:     Ka Ho Ng <k...@freebsd.org>
AuthorDate: 2021-09-11 12:03:38 +0000
Commit:     Ka Ho Ng <k...@freebsd.org>
CommitDate: 2021-09-11 12:04:52 +0000

    md: Add MD_MUSTDEALLOC support
    
    This adds an option to detect if hole-punching is implemented by the
    underlying file system.  If this flag is set, and if the underlying file
    system does not support hole-punching, md(4) fails BIO_DELETE requests
    with EOPNOTSUPP.
    
    Sponsored by:   The FreeBSD Foundation
    Reviewed by:    markj
    Differential Revision:  https://reviews.freebsd.org/D31883
---
 sbin/mdconfig/mdconfig.8 | 35 +++++++++++++++++++++++++++++++++--
 sbin/mdconfig/mdconfig.c |  7 ++++++-
 sys/dev/md/md.c          | 18 ++++++++++++++++--
 sys/sys/mdioctl.h        |  1 +
 4 files changed, 56 insertions(+), 5 deletions(-)

diff --git a/sbin/mdconfig/mdconfig.8 b/sbin/mdconfig/mdconfig.8
index 6d9da8159723..775823fd0bc7 100644
--- a/sbin/mdconfig/mdconfig.8
+++ b/sbin/mdconfig/mdconfig.8
@@ -37,7 +37,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd November 6, 2020
+.Dd August 27, 2021
 .Dt MDCONFIG 8
 .Os
 .Sh NAME
@@ -246,6 +246,34 @@ This can be used with the
 flag to forcibly destroy an
 .Xr md 4
 disk that is still in use.
+.It Oo Cm no Oc Ns Cm mustdealloc
+For
+.Cm vnode
+backed devices: detect whether hole-punching is supported by the underlying 
file
+system.
+If the file system supports hole-punching, then to handle a
+.Dv BIO_DELETE
+request, some or all of the request's operation range may be turned into a hole
+in the file used for backing store.
+Any parts which are not turned into holes are zero-filled in
+the file.
+If the file system does not support
+hole-punching,
+.Dv BIO_DELETE
+requests to the device are not handled and will fail with
+.Er EOPNOTSUPP .
+.Pp
+When
+.Cm mustdealloc
+is not specified or
+.Oo Cm no Oc Ns Cm mustdealloc
+is specified, for a
+.Dv BIO_DELETE
+request, if the file system supports hole-punching, some or all of the 
request's
+operation range may be turned into a hole in the file used for backing store.
+Any parts which are not turned into holes are zero-filled in the file.
+If the file system of the vnode type memory disk does not support 
hole-punching,
+the request's operation range is zero-filled in the file.
 .It Oo Cm no Oc Ns Cm readonly
 Enable/disable readonly mode.
 .It Oo Cm no Oc Ns Cm verify
@@ -339,12 +367,15 @@ gnop create -o 512K md1
 mount /dev/md1.nop /mnt
 .Ed
 .Sh SEE ALSO
+.Xr fpathconf 2 ,
+.Xr fspacectl 2 ,
 .Xr open 2 ,
 .Xr md 4 ,
 .Xr ffs 7 ,
 .Xr gpart 8 ,
 .Xr mdmfs 8 ,
-.Xr malloc 9
+.Xr malloc 9 ,
+.Xr vn_deallocate 9
 .Sh HISTORY
 The
 .Nm
diff --git a/sbin/mdconfig/mdconfig.c b/sbin/mdconfig/mdconfig.c
index 0f76ca6149f1..9f4f3fc3a392 100644
--- a/sbin/mdconfig/mdconfig.c
+++ b/sbin/mdconfig/mdconfig.c
@@ -89,7 +89,8 @@ usage(void)
 "       mdconfig file\n");
        fprintf(stderr, "\t\ttype = {malloc, vnode, swap}\n");
        fprintf(stderr, "\t\toption = {cache, cluster, compress, force,\n");
-       fprintf(stderr, "\t\t          readonly, reserve, ro, verify}\n");
+       fprintf(stderr, "\t\t          mustdealloc, readonly, reserve, ro,\n");
+       fprintf(stderr, "\t\t          verify}\n");
        fprintf(stderr, "\t\tsize = %%d (512 byte blocks), %%db (B),\n");
        fprintf(stderr, "\t\t       %%dk (kB), %%dm (MB), %%dg (GB), \n");
        fprintf(stderr, "\t\t       %%dt (TB), or %%dp (PB)\n");
@@ -194,6 +195,10 @@ main(int argc, char **argv)
                                mdio.md_options |= MD_FORCE;
                        else if (!strcmp(optarg, "noforce"))
                                mdio.md_options &= ~MD_FORCE;
+                       else if (!strcmp(optarg, "mustdealloc"))
+                               mdio.md_options |= MD_MUSTDEALLOC;
+                       else if (!strcmp(optarg, "nomustdealloc"))
+                               mdio.md_options &= ~MD_MUSTDEALLOC;
                        else if (!strcmp(optarg, "readonly"))
                                mdio.md_options |= MD_READONLY;
                        else if (!strcmp(optarg, "noreadonly"))
diff --git a/sys/dev/md/md.c b/sys/dev/md/md.c
index 08fb4b0c6574..92d93f0f0f1d 100644
--- a/sys/dev/md/md.c
+++ b/sys/dev/md/md.c
@@ -90,6 +90,7 @@
 #include <sys/sf_buf.h>
 #include <sys/sysctl.h>
 #include <sys/uio.h>
+#include <sys/unistd.h>
 #include <sys/vnode.h>
 #include <sys/disk.h>
 
@@ -259,6 +260,7 @@ struct md_s {
        struct g_provider *pp;
        int (*start)(struct md_s *sc, struct bio *bp);
        struct devstat *devstat;
+       bool candelete;
 
        /* MD_MALLOC related fields */
        struct indir *indir;
@@ -885,9 +887,12 @@ mdstart_vnode(struct md_s *sc, struct bio *bp)
        case BIO_WRITE:
                auio.uio_rw = UIO_WRITE;
                break;
-       case BIO_DELETE:
        case BIO_FLUSH:
                break;
+       case BIO_DELETE:
+               if (sc->candelete)
+                       break;
+               /* FALLTHROUGH */
        default:
                return (EOPNOTSUPP);
        }
@@ -1176,7 +1181,7 @@ md_handleattr(struct md_s *sc, struct bio *bp)
            (g_handleattr_int(bp, "GEOM::fwsectors", sc->fwsectors) != 0 ||
            g_handleattr_int(bp, "GEOM::fwheads", sc->fwheads) != 0))
                return;
-       if (g_handleattr_int(bp, "GEOM::candelete", 1) != 0)
+       if (g_handleattr_int(bp, "GEOM::candelete", sc->candelete) != 0)
                return;
        if (sc->ident[0] != '\0' &&
            g_handleattr_str(bp, "GEOM::ident", sc->ident) != 0)
@@ -1405,6 +1410,7 @@ mdcreate_vnode(struct md_s *sc, struct md_req *mdr, 
struct thread *td)
        struct nameidata nd;
        char *fname;
        int error, flags;
+       long v;
 
        fname = mdr->md_file;
        if (mdr->md_file_seg == UIO_USERSPACE) {
@@ -1434,6 +1440,13 @@ mdcreate_vnode(struct md_s *sc, struct md_req *mdr, 
struct thread *td)
        error = VOP_GETATTR(nd.ni_vp, &vattr, td->td_ucred);
        if (error != 0)
                goto bad;
+       if ((mdr->md_options & MD_MUSTDEALLOC) != 0) {
+               error = VOP_PATHCONF(nd.ni_vp, _PC_DEALLOC_PRESENT, &v);
+               if (error != 0)
+                       goto bad;
+               if (v == 0)
+                       sc->candelete = false;
+       }
        if (VOP_ISLOCKED(nd.ni_vp) != LK_EXCLUSIVE) {
                vn_lock(nd.ni_vp, LK_UPGRADE | LK_RETRY);
                if (VN_IS_DOOMED(nd.ni_vp)) {
@@ -1690,6 +1703,7 @@ kern_mdattach_locked(struct thread *td, struct md_req 
*mdr)
                mdr->md_unit = sc->unit;
        sc->mediasize = mdr->md_mediasize;
        sc->sectorsize = sectsize;
+       sc->candelete = true;
        error = EDOOFUS;
        switch (sc->type) {
        case MD_MALLOC:
diff --git a/sys/sys/mdioctl.h b/sys/sys/mdioctl.h
index 9e0b0c995341..97464c11149b 100644
--- a/sys/sys/mdioctl.h
+++ b/sys/sys/mdioctl.h
@@ -92,5 +92,6 @@ struct md_ioctl {
 #define MD_ASYNC       0x40    /* Asynchronous mode */
 #define MD_VERIFY      0x80    /* Open file with O_VERIFY (vnode only) */
 #define        MD_CACHE        0x100   /* Cache vnode data */
+#define        MD_MUSTDEALLOC  0x200   /* BIO_DELETE only if dealloc is 
available */
 
 #endif /* _SYS_MDIOCTL_H_*/
_______________________________________________
dev-commits-src-main@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/dev-commits-src-main
To unsubscribe, send any mail to "dev-commits-src-main-unsubscr...@freebsd.org"

Reply via email to