cregit-Linux how code gets into the kernel

Release 4.10 fs/befs/linuxvfs.c

Directory: fs/befs
/*
 * linux/fs/befs/linuxvfs.c
 *
 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
 *
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/stat.h>
#include <linux/nls.h>
#include <linux/buffer_head.h>
#include <linux/vfs.h>
#include <linux/parser.h>
#include <linux/namei.h>
#include <linux/sched.h>
#include <linux/exportfs.h>

#include "befs.h"
#include "btree.h"
#include "inode.h"
#include "datastream.h"
#include "super.h"
#include "io.h"

MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
MODULE_AUTHOR("Will Dyson");
MODULE_LICENSE("GPL");

/* The units the vfs expects inode->i_blocks to be in */

#define VFS_BLOCK_SIZE 512

static int befs_readdir(struct file *, struct dir_context *);
static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
static int befs_readpage(struct file *file, struct page *page);
static sector_t befs_bmap(struct address_space *mapping, sector_t block);
static struct dentry *befs_lookup(struct inode *, struct dentry *,
				  unsigned int);
static struct inode *befs_iget(struct super_block *, unsigned long);
static struct inode *befs_alloc_inode(struct super_block *sb);
static void befs_destroy_inode(struct inode *inode);
static void befs_destroy_inodecache(void);
static int befs_symlink_readpage(struct file *, struct page *);
static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
			char **out, int *out_len);
static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
			char **out, int *out_len);
static void befs_put_super(struct super_block *);
static int befs_remount(struct super_block *, int *, char *);
static int befs_statfs(struct dentry *, struct kstatfs *);
static int parse_options(char *, struct befs_mount_options *);
static struct dentry *befs_fh_to_dentry(struct super_block *sb,
				struct fid *fid, int fh_len, int fh_type);
static struct dentry *befs_fh_to_parent(struct super_block *sb,
				struct fid *fid, int fh_len, int fh_type);


static const struct super_operations befs_sops = {
	.alloc_inode	= befs_alloc_inode,	/* allocate a new inode */
	.destroy_inode	= befs_destroy_inode, /* deallocate an inode */
	.put_super	= befs_put_super,	/* uninit super */
	.statfs		= befs_statfs,	/* statfs */
	.remount_fs	= befs_remount,
	.show_options	= generic_show_options,
};

/* slab cache for befs_inode_info objects */

static struct kmem_cache *befs_inode_cachep;


static const struct file_operations befs_dir_operations = {
	.read		= generic_read_dir,
	.iterate_shared	= befs_readdir,
	.llseek		= generic_file_llseek,
};


static const struct inode_operations befs_dir_inode_operations = {
	.lookup		= befs_lookup,
};


static const struct address_space_operations befs_aops = {
	.readpage	= befs_readpage,
	.bmap		= befs_bmap,
};


static const struct address_space_operations befs_symlink_aops = {
	.readpage	= befs_symlink_readpage,
};


static const struct export_operations befs_export_operations = {
	.fh_to_dentry	= befs_fh_to_dentry,
	.fh_to_parent	= befs_fh_to_parent,
};

/*
 * Called by generic_file_read() to read a page of data
 *
 * In turn, simply calls a generic block read function and
 * passes it the address of befs_get_block, for mapping file
 * positions to disk blocks.
 */

static int befs_readpage(struct file *file, struct page *page) { return block_read_full_page(page, befs_get_block); }

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static sector_t befs_bmap(struct address_space *mapping, sector_t block) { return generic_block_bmap(mapping, block, befs_get_block); }

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alan coxalan cox24100.00%1100.00%
Total24100.00%1100.00%

/* * Generic function to map a file position (block) to a * disk offset (passed back in bh_result). * * Used by many higher level functions. * * Calls befs_fblock2brun() in datastream.c to do the real work. */
static int befs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create) { struct super_block *sb = inode->i_sb; befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; befs_block_run run = BAD_IADDR; int res; ulong disk_off; befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld", (unsigned long)inode->i_ino, (long)block); if (create) { befs_error(sb, "befs_get_block() was asked to write to " "block %ld in inode %lu", (long)block, (unsigned long)inode->i_ino); return -EPERM; } res = befs_fblock2brun(sb, ds, block, &run); if (res != BEFS_OK) { befs_error(sb, "<--- %s for inode %lu, block %ld ERROR", __func__, (unsigned long)inode->i_ino, (long)block); return -EFBIG; } disk_off = (ulong) iaddr2blockno(sb, &run); map_bh(bh_result, inode->i_sb, disk_off); befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu", __func__, (unsigned long)inode->i_ino, (long)block, (unsigned long)disk_off); return 0; }

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alan coxalan cox17281.90%150.00%
fabian frederickfabian frederick3818.10%150.00%
Total210100.00%2100.00%


static struct dentry * befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { struct inode *inode; struct super_block *sb = dir->i_sb; const befs_data_stream *ds = &BEFS_I(dir)->i_data.ds; befs_off_t offset; int ret; int utfnamelen; char *utfname; const char *name = dentry->d_name.name; befs_debug(sb, "---> %s name %pd inode %ld", __func__, dentry, dir->i_ino); /* Convert to UTF-8 */ if (BEFS_SB(sb)->nls) { ret = befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen); if (ret < 0) { befs_debug(sb, "<--- %s ERROR", __func__); return ERR_PTR(ret); } ret = befs_btree_find(sb, ds, utfname, &offset); kfree(utfname); } else { ret = befs_btree_find(sb, ds, name, &offset); } if (ret == BEFS_BT_NOT_FOUND) { befs_debug(sb, "<--- %s %pd not found", __func__, dentry); d_add(dentry, NULL); return ERR_PTR(-ENOENT); } else if (ret != BEFS_OK || offset == 0) { befs_error(sb, "<--- %s Error", __func__); return ERR_PTR(-ENODATA); } inode = befs_iget(dir->i_sb, (ino_t) offset); if (IS_ERR(inode)) return ERR_CAST(inode); d_add(dentry, inode); befs_debug(sb, "<--- %s", __func__); return NULL; }

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alan coxalan cox25588.24%111.11%
fabian frederickfabian frederick134.50%111.11%
salah trikisalah triki72.42%111.11%
david howellsdavid howells62.08%111.11%
al viroal viro62.08%333.33%
luis de bethencourtluis de bethencourt10.35%111.11%
trond myklebusttrond myklebust10.35%111.11%
Total289100.00%9100.00%


static int befs_readdir(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); struct super_block *sb = inode->i_sb; const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; befs_off_t value; int result; size_t keysize; char keybuf[BEFS_NAME_LEN + 1]; befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld", __func__, file, inode->i_ino, ctx->pos); while (1) { result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1, keybuf, &keysize, &value); if (result == BEFS_ERR) { befs_debug(sb, "<--- %s ERROR", __func__); befs_error(sb, "IO error reading %pD (inode %lu)", file, inode->i_ino); return -EIO; } else if (result == BEFS_BT_END) { befs_debug(sb, "<--- %s END", __func__); return 0; } else if (result == BEFS_BT_EMPTY) { befs_debug(sb, "<--- %s Empty directory", __func__); return 0; } /* Convert to NLS */ if (BEFS_SB(sb)->nls) { char *nlsname; int nlsnamelen; result = befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen); if (result < 0) { befs_debug(sb, "<--- %s ERROR", __func__); return result; } if (!dir_emit(ctx, nlsname, nlsnamelen, (ino_t) value, DT_UNKNOWN)) { kfree(nlsname); return 0; } kfree(nlsname); } else { if (!dir_emit(ctx, keybuf, keysize, (ino_t) value, DT_UNKNOWN)) return 0; } ctx->pos++; } }

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alan coxalan cox24076.68%111.11%
al viroal viro5116.29%555.56%
fabian frederickfabian frederick144.47%111.11%
luis de bethencourtluis de bethencourt82.56%222.22%
Total313100.00%9100.00%


static struct inode * befs_alloc_inode(struct super_block *sb) { struct befs_inode_info *bi; bi = kmem_cache_alloc(befs_inode_cachep, GFP_KERNEL); if (!bi) return NULL; return &bi->vfs_inode; }

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alan coxalan cox4097.56%150.00%
christoph lameterchristoph lameter12.44%150.00%
Total41100.00%2100.00%


static void befs_i_callback(struct rcu_head *head) { struct inode *inode = container_of(head, struct inode, i_rcu); kmem_cache_free(befs_inode_cachep, BEFS_I(inode)); }

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alan coxalan cox1850.00%150.00%
nick pigginnick piggin1850.00%150.00%
Total36100.00%2100.00%


static void befs_destroy_inode(struct inode *inode) { call_rcu(&inode->i_rcu, befs_i_callback); }

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nick pigginnick piggin21100.00%1100.00%
Total21100.00%1100.00%


static void init_once(void *foo) { struct befs_inode_info *bi = (struct befs_inode_info *) foo; inode_init_once(&bi->vfs_inode); }

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alan coxalan cox2790.00%150.00%
christoph lameterchristoph lameter310.00%150.00%
Total30100.00%2100.00%


static struct inode *befs_iget(struct super_block *sb, unsigned long ino) { struct buffer_head *bh; befs_inode *raw_inode; struct befs_sb_info *befs_sb = BEFS_SB(sb); struct befs_inode_info *befs_ino; struct inode *inode; befs_debug(sb, "---> %s inode = %lu", __func__, ino); inode = iget_locked(sb, ino); if (!inode) return ERR_PTR(-ENOMEM); if (!(inode->i_state & I_NEW)) return inode; befs_ino = BEFS_I(inode); /* convert from vfs's inode number to befs's inode number */ befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino); befs_debug(sb, " real inode number [%u, %hu, %hu]", befs_ino->i_inode_num.allocation_group, befs_ino->i_inode_num.start, befs_ino->i_inode_num.len); bh = sb_bread(sb, inode->i_ino); if (!bh) { befs_error(sb, "unable to read inode block - " "inode = %lu", inode->i_ino); goto unacquire_none; } raw_inode = (befs_inode *) bh->b_data; befs_dump_inode(sb, raw_inode); if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) { befs_error(sb, "Bad inode: %lu", inode->i_ino); goto unacquire_bh; } inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode); /* * set uid and gid. But since current BeOS is single user OS, so * you can change by "uid" or "gid" options. */ inode->i_uid = befs_sb->mount_opts.use_uid ? befs_sb->mount_opts.uid : make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid)); inode->i_gid = befs_sb->mount_opts.use_gid ? befs_sb->mount_opts.gid : make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid)); set_nlink(inode, 1); /* * BEFS's time is 64 bits, but current VFS is 32 bits... * BEFS don't have access time. Nor inode change time. VFS * doesn't have creation time. * Also, the lower 16 bits of the last_modified_time and * create_time are just a counter to help ensure uniqueness * for indexing purposes. (PFD, page 54) */ inode->i_mtime.tv_sec = fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16; inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */ inode->i_ctime = inode->i_mtime; inode->i_atime = inode->i_mtime; befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num); befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent); befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes); befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags); if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){ inode->i_size = 0; inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE; strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink, BEFS_SYMLINK_LEN); } else { int num_blks; befs_ino->i_data.ds = fsds_to_cpu(sb, &raw_inode->data.datastream); num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds); inode->i_blocks = num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE); inode->i_size = befs_ino->i_data.ds.size; } inode->i_mapping->a_ops = &befs_aops; if (S_ISREG(inode->i_mode)) { inode->i_fop = &generic_ro_fops; } else if (S_ISDIR(inode->i_mode)) { inode->i_op = &befs_dir_inode_operations; inode->i_fop = &befs_dir_operations; } else if (S_ISLNK(inode->i_mode)) { if (befs_ino->i_flags & BEFS_LONG_SYMLINK) { inode->i_op = &page_symlink_inode_operations; inode_nohighmem(inode); inode->i_mapping->a_ops = &befs_symlink_aops; } else { inode->i_link = befs_ino->i_data.symlink; inode->i_op = &simple_symlink_inode_operations; } } else { befs_error(sb, "Inode %lu is not a regular file, " "directory or symlink. THAT IS WRONG! BeFS has no " "on disk special files", inode->i_ino); goto unacquire_bh; } brelse(bh); befs_debug(sb, "<--- %s", __func__); unlock_new_inode(inode); return inode; unacquire_bh: brelse(bh); unacquire_none: iget_failed(inode); befs_debug(sb, "<--- %s - Bad inode", __func__); return ERR_PTR(-EIO); }

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alan coxalan cox54276.99%14.35%
david howellsdavid howells588.24%14.35%
al viroal viro456.39%417.39%
eric w. biedermaneric w. biederman121.70%14.35%
fabian frederickfabian frederick121.70%417.39%
andi kleenandi kleen101.42%14.35%
rakesh panditrakesh pandit60.85%14.35%
adrian bunkadrian bunk50.71%14.35%
miklos szeredimiklos szeredi40.57%14.35%
salah trikisalah triki30.43%28.70%
andrew mortonandrew morton30.43%28.70%
jesper juhljesper juhl10.14%14.35%
christoph hellwigchristoph hellwig10.14%14.35%
luis de bethencourtluis de bethencourt10.14%14.35%
rusty russellrusty russell10.14%14.35%
Total704100.00%23100.00%

/* Initialize the inode cache. Called at fs setup. * * Taken from NFS implementation by Al Viro. */
static int __init befs_init_inodecache(void) { befs_inode_cachep = kmem_cache_create("befs_inode_cache", sizeof (struct befs_inode_info), 0, (SLAB_RECLAIM_ACCOUNT| SLAB_MEM_SPREAD|SLAB_ACCOUNT), init_once); if (befs_inode_cachep == NULL) return -ENOMEM; return 0; }

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alan coxalan cox3982.98%116.67%
paul jacksonpaul jackson48.51%233.33%
vladimir davydovvladimir davydov24.26%116.67%
andrew mortonandrew morton12.13%116.67%
fabian frederickfabian frederick12.13%116.67%
Total47100.00%6100.00%

/* Called at fs teardown. * * Taken from NFS implementation by Al Viro. */
static void befs_destroy_inodecache(void) { /* * Make sure all delayed rcu free inodes are flushed before we * destroy cache. */ rcu_barrier(); kmem_cache_destroy(befs_inode_cachep); }

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alan coxalan cox1376.47%150.00%
kirill a. shutemovkirill a. shutemov423.53%150.00%
Total17100.00%2100.00%

/* * The inode of symbolic link is different to data stream. * The data stream become link name. Unless the LONG_SYMLINK * flag is set. */
static int befs_symlink_readpage(struct file *unused, struct page *page) { struct inode *inode = page->mapping->host; struct super_block *sb = inode->i_sb; struct befs_inode_info *befs_ino = BEFS_I(inode); befs_data_stream *data = &befs_ino->i_data.ds; befs_off_t len = data->size; char *link = page_address(page); if (len == 0 || len > PAGE_SIZE) { befs_error(sb, "Long symlink with illegal length"); goto fail; } befs_debug(sb, "Follow long symlink"); if (befs_read_lsymlink(sb, data, link, len) != len) { befs_error(sb, "Failed to read entire long symlink"); goto fail; } link[len - 1] = '\0'; SetPageUptodate(page); unlock_page(page); return 0; fail: SetPageError(page); unlock_page(page); return -EIO; }

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al viroal viro8047.90%555.56%
alan coxalan cox6237.13%111.11%
timo warnstimo warns158.98%111.11%
duane griffinduane griffin95.39%111.11%
fabian frederickfabian frederick10.60%111.11%
Total167100.00%9100.00%

/* * UTF-8 to NLS charset convert routine * * Uses uni2char() / char2uni() rather than the nls tables directly */
static int befs_utf2nls(struct super_block *sb, const char *in, int in_len, char **out, int *out_len) { struct nls_table *nls = BEFS_SB(sb)->nls; int i, o; unicode_t uni; int unilen, utflen; char *result; /* The utf8->nls conversion won't make the final nls string bigger * than the utf one, but if the string is pure ascii they'll have the * same width and an extra char is needed to save the additional \0 */ int maxlen = in_len + 1; befs_debug(sb, "---> %s", __func__); if (!nls) { befs_error(sb, "%s called with no NLS table loaded", __func__); return -EINVAL; } *out = result = kmalloc(maxlen, GFP_NOFS); if (!*out) return -ENOMEM; for (i = o = 0; i < in_len; i += utflen, o += unilen) { /* convert from UTF-8 to Unicode */ utflen = utf8_to_utf32(&in[i], in_len - i, &uni); if (utflen < 0) goto conv_err; /* convert from Unicode to nls */ if (uni > MAX_WCHAR_T) goto conv_err; unilen = nls->uni2char(uni, &result[o], in_len - o); if (unilen < 0) goto conv_err; } result[o] = '\0'; *out_len = o; befs_debug(sb, "<--- %s", __func__); return o; conv_err: befs_error(sb, "Name using character set %s contains a character that " "cannot be converted to unicode.", nls->charset); befs_debug(sb, "<--- %s", __func__); kfree(result); return -EILSEQ; }

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alan coxalan cox22285.38%114.29%
alan sternalan stern145.38%114.29%
fabian frederickfabian frederick124.62%114.29%
rusty russellrusty russell51.92%114.29%
andrew mortonandrew morton41.54%228.57%
diego calleja garciadiego calleja garcia31.15%114.29%
Total260100.00%7100.00%

/** * befs_nls2utf - Convert NLS string to utf8 encodeing * @sb: Superblock * @in: Input string buffer in NLS format * @in_len: Length of input string in bytes * @out: The output string in UTF-8 format * @out_len: Length of the output buffer * * Converts input string @in, which is in the format of the loaded NLS map, * into a utf8 string. * * The destination string @out is allocated by this function and the caller is * responsible for freeing it with kfree() * * On return, *@out_len is the length of @out in bytes. * * On success, the return value is the number of utf8 characters written to * the output buffer @out. * * On Failure, a negative number coresponding to the error code is returned. */
static int befs_nls2utf(struct super_block *sb, const char *in, int in_len, char **out, int *out_len) { struct nls_table *nls = BEFS_SB(sb)->nls; int i, o; wchar_t uni; int unilen, utflen; char *result; /* * There are nls characters that will translate to 3-chars-wide UTF-8 * characters, an additional byte is needed to save the final \0 * in special cases */ int maxlen = (3 * in_len) + 1; befs_debug(sb, "---> %s\n", __func__); if (!nls) { befs_error(sb, "%s called with no NLS table loaded.", __func__); return -EINVAL; } *out = result = kmalloc(maxlen, GFP_NOFS); if (!*out) { *out_len = 0; return -ENOMEM; } for (i = o = 0; i < in_len; i += unilen, o += utflen) { /* convert from nls to unicode */ unilen = nls->char2uni(&in[i], in_len - i, &uni); if (unilen < 0) goto conv_err; /* convert from unicode to UTF-8 */ utflen = utf32_to_utf8(uni, &result[o]