| Message ID | 20240821125137.36304-1-andrii.polianytsia@globallogic.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] fs/exfat: add NFS export support | expand |
On Wed, Aug 21, 2024 at 03:51:37PM +0300, andrii.polianytsia@globallogic.com wrote: > From: Andrii Polianytsia <andrii.polianytsia@globallogic.com> > > Add NFS export support to the exFAT filesystem by implementing > the necessary export operations in fs/exfat/super.c. Enable > exFAT filesystems to be exported and accessed over NFS, enhancing > their utility in networked environments. > > Introduce the exfat_export_ops structure, which includes > functions to handle file handles and inode lookups necessary for NFS > operations. > > Given the similarities between exFAT and FAT filesystems, and that FAT > supports exporting via NFS, this implementation is based on the existing logic > in the FAT filesystem's NFS export code (fs/fat/nfs.c). > > Signed-off-by: Andrii Polianytsia <andrii.polianytsia@globallogic.com> > Signed-off-by: Sergii Boryshchenko <sergii.boryshchenko@globallogic.com> > --- > v2 > Add information about similar implementation logic > from fs/fat/nfs.c to the commit message. > > fs/exfat/super.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 65 insertions(+) > > diff --git a/fs/exfat/super.c b/fs/exfat/super.c > index 323ecebe6f0e..cb6dcafc3007 100644 > --- a/fs/exfat/super.c > +++ b/fs/exfat/super.c > @@ -18,6 +18,7 @@ > #include <linux/nls.h> > #include <linux/buffer_head.h> > #include <linux/magic.h> > +#include <linux/exportfs.h> > > #include "exfat_raw.h" > #include "exfat_fs.h" > @@ -195,6 +196,69 @@ static const struct super_operations exfat_sops = { > .show_options = exfat_show_options, > }; > > +/** > + * exfat_export_get_inode - Get inode for export operations > + * @sb: Superblock pointer > + * @ino: Inode number > + * @generation: Generation number > + * > + * Returns pointer to inode or error pointer in case of an error. > + */ > +static struct inode *exfat_export_get_inode(struct super_block *sb, u64 ino, > + u32 generation) > +{ > + struct inode *inode = NULL; > + > + if (ino == 0) > + return ERR_PTR(-ESTALE); > + > + inode = ilookup(sb, ino); > + if (inode && generation && inode->i_generation != generation) { > + iput(inode); > + return ERR_PTR(-ESTALE); > + } > + > + return inode; > +} > + > +/** > + * exfat_fh_to_dentry - Convert file handle to dentry > + * @sb: Superblock pointer > + * @fid: File identifier > + * @fh_len: Length of the file handle > + * @fh_type: Type of the file handle > + * > + * Returns dentry corresponding to the file handle. > + */ > +static struct dentry *exfat_fh_to_dentry(struct super_block *sb, > + struct fid *fid, int fh_len, int fh_type) > +{ > + return generic_fh_to_dentry(sb, fid, fh_len, fh_type, > + exfat_export_get_inode); > +} > + > +/** > + * exfat_fh_to_parent - Convert file handle to parent dentry > + * @sb: Superblock pointer > + * @fid: File identifier > + * @fh_len: Length of the file handle > + * @fh_type: Type of the file handle > + * > + * Returns parent dentry corresponding to the file handle. > + */ > +static struct dentry *exfat_fh_to_parent(struct super_block *sb, > + struct fid *fid, int fh_len, int fh_type) > +{ > + return generic_fh_to_parent(sb, fid, fh_len, fh_type, > + exfat_export_get_inode); > +} > + > +static const struct export_operations exfat_export_ops = { > + .encode_fh = generic_encode_ino32_fh, > + .fh_to_dentry = exfat_fh_to_dentry, > + .fh_to_parent = exfat_fh_to_parent, > +}; > + > enum { > Opt_uid, > Opt_gid, > @@ -633,6 +697,7 @@ static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) > sb->s_flags |= SB_NODIRATIME; > sb->s_magic = EXFAT_SUPER_MAGIC; > sb->s_op = &exfat_sops; > + sb->s_export_op = &exfat_export_ops; > > sb->s_time_gran = 10 * NSEC_PER_MSEC; > sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS; > -- > 2.25.1 > > If NamJae is interested in taking this patch -- Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
diff --git a/fs/exfat/super.c b/fs/exfat/super.c index 323ecebe6f0e..cb6dcafc3007 100644 --- a/fs/exfat/super.c +++ b/fs/exfat/super.c @@ -18,6 +18,7 @@ #include <linux/nls.h> #include <linux/buffer_head.h> #include <linux/magic.h> +#include <linux/exportfs.h> #include "exfat_raw.h" #include "exfat_fs.h" @@ -195,6 +196,69 @@ static const struct super_operations exfat_sops = { .show_options = exfat_show_options, }; +/** + * exfat_export_get_inode - Get inode for export operations + * @sb: Superblock pointer + * @ino: Inode number + * @generation: Generation number + * + * Returns pointer to inode or error pointer in case of an error. + */ +static struct inode *exfat_export_get_inode(struct super_block *sb, u64 ino, + u32 generation) +{ + struct inode *inode = NULL; + + if (ino == 0) + return ERR_PTR(-ESTALE); + + inode = ilookup(sb, ino); + if (inode && generation && inode->i_generation != generation) { + iput(inode); + return ERR_PTR(-ESTALE); + } + + return inode; +} + +/** + * exfat_fh_to_dentry - Convert file handle to dentry + * @sb: Superblock pointer + * @fid: File identifier + * @fh_len: Length of the file handle + * @fh_type: Type of the file handle + * + * Returns dentry corresponding to the file handle. + */ +static struct dentry *exfat_fh_to_dentry(struct super_block *sb, + struct fid *fid, int fh_len, int fh_type) +{ + return generic_fh_to_dentry(sb, fid, fh_len, fh_type, + exfat_export_get_inode); +} + +/** + * exfat_fh_to_parent - Convert file handle to parent dentry + * @sb: Superblock pointer + * @fid: File identifier + * @fh_len: Length of the file handle + * @fh_type: Type of the file handle + * + * Returns parent dentry corresponding to the file handle. + */ +static struct dentry *exfat_fh_to_parent(struct super_block *sb, + struct fid *fid, int fh_len, int fh_type) +{ + return generic_fh_to_parent(sb, fid, fh_len, fh_type, + exfat_export_get_inode); +} + +static const struct export_operations exfat_export_ops = { + .encode_fh = generic_encode_ino32_fh, + .fh_to_dentry = exfat_fh_to_dentry, + .fh_to_parent = exfat_fh_to_parent, +}; + enum { Opt_uid, Opt_gid, @@ -633,6 +697,7 @@ static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_flags |= SB_NODIRATIME; sb->s_magic = EXFAT_SUPER_MAGIC; sb->s_op = &exfat_sops; + sb->s_export_op = &exfat_export_ops; sb->s_time_gran = 10 * NSEC_PER_MSEC; sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS;