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Kernel Debug

== uio ==

OSX uio is now opaque, so we can't fiddle with the insides of uid-> anymore. Instead there are a number of API calls to use. uio_offset() etc.

In addition to that, Apple kernel defines "uio_t" as typedef struct uio *uio_t; and use it as "uio_t uio;" and ZFS defines it as typedef struct uio uio_t; and use it as "uio_t *uio;".

MacZFS uses #define uio_t struct uio

to work around that, so that is still around, however, I have generally replaced it with

uio_t *uio; -> struct uio *uio;

At the moment, including <sys/uio.h> will pull in spl/include/sys/uio.h;

#undef uio_t
#include_next <sys/uio.h>
#define uio_t struct uio

which creates a #define over the typedef. The same for sys/vnode.h

== vnode / inode ==

Linux's 'inode' are called 'vnode' on BSD systems, and on OSX it is opaque. So again, we can not see inside vnode struct.

Again we have the same "vnode_t" problem as with uio_t.

 vnode_t *vp;   ->  struct vnode *vp;

Other porting items, minus-line means the ZFS original source, to be removed, and plus-line is the replacement.

-zfs_sb_t        *zsb;
Is a linux thing, we replace with

+zfsvfs_t *zfsvfs;

-ZTOI(zp)
+ZTOV(zp);


-        iput(ZTOI(dzp));
-    VN_RELE(ZTOV(zp));
+ vnode_put(ZTOV(zp));

-flock64_t
+struct flock

-ZTOZSB(zp))
+zfsvfs_t *zfsvfs = zp->z_zfsvfs;

- ZTOZSB(zp)->i_mode
+vnode_vtype(vp)

-(S_ISDIR(ZTOI(dzp)->i_mode)
vnode_isdir(ZTOV(dzp))

-kauth_acl_t *vsecp
+vsecattr_t *vsecp


-ZFS_POSTPROCESS_ZP
+zfs_attach_vnode(xzp);


-       if (mask & AT_SIZE)
+       if (VATTR_IS_ACTIVE(vap, va_data_size))


-struct super_block *sb
-vfs_t *vfsp
+

-uio->uio_iovcnt
+uio_iovcnt(uio)

-uio->uio_iov
+uio_curriovbase(uio)

-uio->uio_resid
+uio_resid(uio)

-uio->uio_loffset
+uio_offset(uio)


-       uio_prefaultpages(MIN(n, max_blksz), uio);
+       zfs_prefault_write(n, uio);

== strdup ==

In kernel, use spa_strdup().

== API changes ==

Before

    error = dmu_objset_open(osname, DMU_OST_ZFS, mode, &zfsvfs->z_os);
         dmu_objset_close(zfsvfs->z_os);

after

 	error = dmu_objset_own(osname, DMU_OST_ZFS,
                           readonly ? B_TRUE : B_FALSE, &zfsvfs, &zfsvfs->z_os);
            dmu_objset_disown(zfsvfs->z_os, &zfsvfs);

Where "&zfsvfs" is the tag "argument" (passed along as void *)