From 185503c7a2209fb3f6d487529089faadf05ed89d Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Sat, 3 Nov 2012 11:42:59 +1100 Subject: [PATCH] fat: restructure export operations Define two nfs export_operation structures,one for 'stale_rw' mounts and the other for 'nostale_ro'.The former uses the generic export_encode_fh function to encode file handle, while the latter uses fat_encode_fh(). Since inode number is not needed for nostale_ro, remove it from struct fat_fid and repack other needed info viz. i_pos and i_generation. Signed-off-by: Namjae Jeon Signed-off-by: Ravishankar N Signed-off-by: Amit Sahrawat Cc: OGAWA Hirofumi Cc: "J. Bruce Fields" Signed-off-by: Andrew Morton --- fs/fat/fat.h | 2 + fs/fat/inode.c | 12 ++--- fs/fat/nfs.c | 127 ++++++++++++++++++++++++++++++++++++++----------- 3 files changed, 104 insertions(+), 37 deletions(-) diff --git a/fs/fat/fat.h b/fs/fat/fat.h index febc1ccaae72..65f9149bed79 100644 --- a/fs/fat/fat.h +++ b/fs/fat/fat.h @@ -391,6 +391,8 @@ void fat_cache_destroy(void); /* fat/nfs.c */ struct fid; +extern const struct export_operations fat_export_ops; +extern const struct export_operations fat_export_ops_nostale; extern int fat_encode_fh(struct inode *inode, __u32 *fh, int *lenp, struct inode *parent); extern struct dentry *fat_fh_to_dentry(struct super_block *sb, struct fid *fid, diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 80c6fddee396..34253dc08aa3 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -18,7 +18,6 @@ #include #include #include -#include #include #include #include @@ -703,13 +702,6 @@ static const struct super_operations fat_sops = { .show_options = fat_show_options, }; -static const struct export_operations fat_export_ops = { - .encode_fh = fat_encode_fh, - .fh_to_dentry = fat_fh_to_dentry, - .fh_to_parent = fat_fh_to_parent, - .get_parent = fat_get_parent, -}; - static int fat_show_options(struct seq_file *m, struct dentry *root) { struct msdos_sb_info *sbi = MSDOS_SB(root->d_sb); @@ -1118,8 +1110,10 @@ out: opts->allow_utime = ~opts->fs_dmask & (S_IWGRP | S_IWOTH); if (opts->unicode_xlate) opts->utf8 = 0; - if (opts->nfs == FAT_NFS_NOSTALE_RO) + if (opts->nfs == FAT_NFS_NOSTALE_RO) { sb->s_flags |= MS_RDONLY; + sb->s_export_op = &fat_export_ops_nostale; + } return 0; } diff --git a/fs/fat/nfs.c b/fs/fat/nfs.c index 671a75d2fc59..0abfacffda71 100644 --- a/fs/fat/nfs.c +++ b/fs/fat/nfs.c @@ -15,13 +15,17 @@ #include "fat.h" struct fat_fid { - u32 ino; - u32 gen; - u64 i_pos; - u32 parent_ino; - u32 parent_gen; + u32 i_gen; + u32 i_pos_low; + u16 i_pos_hi; + u16 parent_i_pos_hi; + u32 parent_i_pos_low; + u32 parent_i_gen; } __packed; +#define FILEID_FAT_WITHOUT_PARENT (offsetof(struct fat_fid, parent_i_pos_hi)/4) +#define FILEID_FAT_WITH_PARENT (sizeof(struct fat_fid)/4) + /** * Look up a directory inode given its starting cluster. */ @@ -47,15 +51,24 @@ static struct inode *fat_dget(struct super_block *sb, int i_logstart) return inode; } +static struct inode *fat_ilookup(struct super_block *sb, u64 ino, loff_t i_pos) +{ + if (MSDOS_SB(sb)->options.nfs == FAT_NFS_NOSTALE_RO) + return fat_iget(sb, i_pos); + + else { + if ((ino < MSDOS_ROOT_INO) || (ino == MSDOS_FSINFO_INO)) + return NULL; + return ilookup(sb, ino); + } +} + static struct inode *fat_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation, loff_t i_pos) { - struct inode *inode; - if ((ino < MSDOS_ROOT_INO) || (ino == MSDOS_FSINFO_INO)) - return NULL; + struct inode *inode = fat_ilookup(sb, ino, i_pos); - inode = ilookup(sb, ino); if (inode && generation && (inode->i_generation != generation)) { iput(inode); inode = NULL; @@ -89,7 +102,8 @@ static struct inode *fat_nfs_get_inode(struct super_block *sb, int -fat_encode_fh(struct inode *inode, __u32 *fh, int *lenp, struct inode *parent) +fat_encode_fh_nostale(struct inode *inode, __u32 *fh, int *lenp, + struct inode *parent) { int len = *lenp; struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); @@ -97,24 +111,26 @@ fat_encode_fh(struct inode *inode, __u32 *fh, int *lenp, struct inode *parent) loff_t i_pos; int type = FILEID_INO32_GEN; - if (parent && (len < 5)) { - *lenp = 5; + if (parent && (len < FILEID_FAT_WITH_PARENT)) { + *lenp = FILEID_FAT_WITH_PARENT; return 255; - } else if (len < 3) { - *lenp = 3; + } else if (len < FILEID_FAT_WITHOUT_PARENT) { + *lenp = FILEID_FAT_WITHOUT_PARENT; return 255; } i_pos = fat_i_pos_read(sbi, inode); - *lenp = 3; - fid->ino = inode->i_ino; - fid->gen = inode->i_generation; - fid->i_pos = i_pos; + *lenp = FILEID_FAT_WITHOUT_PARENT; + fid->i_gen = inode->i_generation; + fid->i_pos_low = i_pos & 0xFFFFFFFF; + fid->i_pos_hi = (i_pos >> 32) & 0xFF; if (parent) { - fid->parent_ino = parent->i_ino; - fid->parent_gen = parent->i_generation; + i_pos = fat_i_pos_read(sbi, parent); + fid->parent_i_pos_hi = (i_pos >> 32) & 0xFF; + fid->parent_i_pos_low = i_pos & 0xFFFFFFFF; + fid->parent_i_gen = parent->i_generation; type = FILEID_INO32_GEN_PARENT; - *lenp = 5; + *lenp = FILEID_FAT_WITH_PARENT; } return type; @@ -128,14 +144,36 @@ struct dentry *fat_fh_to_dentry(struct super_block *sb, struct fid *fh, int fh_len, int fh_type) { struct inode *inode = NULL; - struct fat_fid *fid = (struct fat_fid *)fh; - if (fh_len < 3) + if (fh_len < 2) return NULL; switch (fh_type) { case FILEID_INO32_GEN: case FILEID_INO32_GEN_PARENT: - inode = fat_nfs_get_inode(sb, fid->ino, fid->gen, fid->i_pos); + inode = fat_nfs_get_inode(sb, fh->i32.ino, fh->i32.gen, 0); + break; + } + + return d_obtain_alias(inode); +} +struct dentry *fat_fh_to_dentry_nostale(struct super_block *sb, struct fid *fh, + int fh_len, int fh_type) +{ + struct inode *inode = NULL; + struct fat_fid *fid = (struct fat_fid *)fh; + loff_t i_pos; + + switch (fh_type) { + case FILEID_INO32_GEN: + if (fh_len < FILEID_FAT_WITHOUT_PARENT) + return NULL; + case FILEID_INO32_GEN_PARENT: + if ((fh_len < FILEID_FAT_WITH_PARENT) && + (fh_type == FILEID_INO32_GEN_PARENT)) + return NULL; + i_pos = fid->i_pos_hi; + i_pos = (i_pos << 32) | (fid->i_pos_low); + inode = fat_nfs_get_inode(sb, 0, fid->i_gen, i_pos); break; } @@ -147,18 +185,39 @@ struct dentry *fat_fh_to_dentry(struct super_block *sb, struct fid *fh, * Find the parent for a file specified by NFS handle. * This requires that the handle contain the i_ino of the parent. */ -struct dentry *fat_fh_to_parent(struct super_block *sb, struct fid *fh, +struct dentry *fat_fh_to_parent(struct super_block *sb, struct fid *fid, + int fh_len, int fh_type) +{ + struct inode *inode = NULL; + + if (fh_len < 2) + return NULL; + + switch (fh_type) { + case FILEID_INO32_GEN: + case FILEID_INO32_GEN_PARENT: + inode = fat_nfs_get_inode(sb, fid->i32.ino, fid->i32.gen, 0); + break; + } + + return d_obtain_alias(inode); +} + +struct dentry *fat_fh_to_parent_nostale(struct super_block *sb, struct fid *fh, int fh_len, int fh_type) { struct inode *inode = NULL; struct fat_fid *fid = (struct fat_fid *)fh; - if (fh_len < 5) + loff_t i_pos; + + if (fh_len < FILEID_FAT_WITH_PARENT) return NULL; switch (fh_type) { case FILEID_INO32_GEN_PARENT: - inode = fat_nfs_get_inode(sb, fid->parent_ino, fid->parent_gen, - fid->i_pos); + i_pos = fid->parent_i_pos_hi; + i_pos = (i_pos << 32) | (fid->parent_i_pos_low); + inode = fat_nfs_get_inode(sb, 0, fid->parent_i_gen, i_pos); break; } @@ -303,3 +362,15 @@ out: return d_obtain_alias(parent_inode); } + +const struct export_operations fat_export_ops = { + .fh_to_dentry = fat_fh_to_dentry, + .fh_to_parent = fat_fh_to_parent, + .get_parent = fat_get_parent, +}; +const struct export_operations fat_export_ops_nostale = { + .encode_fh = fat_encode_fh_nostale, + .fh_to_dentry = fat_fh_to_dentry_nostale, + .fh_to_parent = fat_fh_to_parent_nostale, + .get_parent = fat_get_parent, +}; -- 2.39.5