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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-15 13:49:27 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-15 13:49:27 -0700 |
commit | e44740c1a94b5d39b093045920f543a7bc135584 (patch) | |
tree | 3dc097e078653cc520476ac997e1765b90703a56 /fs/hostfs/hostfs_kern.c | |
parent | d613896926be608796bb80454256a07b55fe0e87 (diff) | |
parent | fe205bdd1321f95f8f3c35d243ea7cb22af8fbe1 (diff) | |
download | op-kernel-dev-e44740c1a94b5d39b093045920f543a7bc135584.zip op-kernel-dev-e44740c1a94b5d39b093045920f543a7bc135584.tar.gz |
Merge tag 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
- hostfs saw a face lifting
- old/broken stuff was removed (SMP, HIGHMEM, SKAS3/4)
- random cleanups and bug fixes
* tag 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (26 commits)
um: Print minimum physical memory requirement
um: Move uml_postsetup in the init_thread stack
um: add a kmsg_dumper
x86, UML: fix integer overflow in ELF_ET_DYN_BASE
um: hostfs: Reduce number of syscalls in readdir
um: Remove broken highmem support
um: Remove broken SMP support
um: Remove SKAS3/4 support
um: Remove ppc cruft
um: Remove ia64 cruft
um: Remove dead code from stacktrace
hostfs: No need to box and later unbox the file mode
hostfs: Use page_offset()
hostfs: Set page flags in hostfs_readpage() correctly
hostfs: Remove superfluous initializations in hostfs_open()
hostfs: hostfs_open: Reset open flags upon each retry
hostfs: Remove superfluous test in hostfs_open()
hostfs: Report append flag in ->show_options()
hostfs: Use __getname() in follow_link
hostfs: Remove open coded strcpy()
...
Diffstat (limited to 'fs/hostfs/hostfs_kern.c')
-rw-r--r-- | fs/hostfs/hostfs_kern.c | 112 |
1 files changed, 62 insertions, 50 deletions
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c index e021188..b83a034 100644 --- a/fs/hostfs/hostfs_kern.c +++ b/fs/hostfs/hostfs_kern.c @@ -24,6 +24,7 @@ struct hostfs_inode_info { int fd; fmode_t mode; struct inode vfs_inode; + struct mutex open_mutex; }; static inline struct hostfs_inode_info *HOSTFS_I(struct inode *inode) @@ -92,16 +93,22 @@ static char *__dentry_name(struct dentry *dentry, char *name) __putname(name); return NULL; } + + /* + * This function relies on the fact that dentry_path_raw() will place + * the path name at the end of the provided buffer. + */ + BUG_ON(p + strlen(p) + 1 != name + PATH_MAX); + strlcpy(name, root, PATH_MAX); if (len > p - name) { __putname(name); return NULL; } - if (p > name + len) { - char *s = name + len; - while ((*s++ = *p++) != '\0') - ; - } + + if (p > name + len) + strcpy(name + len, p); + return name; } @@ -135,21 +142,19 @@ static char *follow_link(char *link) int len, n; char *name, *resolved, *end; - len = 64; - while (1) { + name = __getname(); + if (!name) { n = -ENOMEM; - name = kmalloc(len, GFP_KERNEL); - if (name == NULL) - goto out; - - n = hostfs_do_readlink(link, name, len); - if (n < len) - break; - len *= 2; - kfree(name); + goto out_free; } + + n = hostfs_do_readlink(link, name, PATH_MAX); if (n < 0) goto out_free; + else if (n == PATH_MAX) { + n = -E2BIG; + goto out_free; + } if (*name == '/') return name; @@ -168,13 +173,12 @@ static char *follow_link(char *link) } sprintf(resolved, "%s%s", link, name); - kfree(name); + __putname(name); kfree(link); return resolved; out_free: - kfree(name); - out: + __putname(name); return ERR_PTR(n); } @@ -225,6 +229,7 @@ static struct inode *hostfs_alloc_inode(struct super_block *sb) hi->fd = -1; hi->mode = 0; inode_init_once(&hi->vfs_inode); + mutex_init(&hi->open_mutex); return &hi->vfs_inode; } @@ -257,6 +262,9 @@ static int hostfs_show_options(struct seq_file *seq, struct dentry *root) if (strlen(root_path) > offset) seq_printf(seq, ",%s", root_path + offset); + if (append) + seq_puts(seq, ",append"); + return 0; } @@ -284,6 +292,7 @@ static int hostfs_readdir(struct file *file, struct dir_context *ctx) if (dir == NULL) return -error; next = ctx->pos; + seek_dir(dir, next); while ((name = read_dir(dir, &next, &ino, &len, &type)) != NULL) { if (!dir_emit(ctx, name, len, ino, type)) break; @@ -293,13 +302,12 @@ static int hostfs_readdir(struct file *file, struct dir_context *ctx) return 0; } -static int hostfs_file_open(struct inode *ino, struct file *file) +static int hostfs_open(struct inode *ino, struct file *file) { - static DEFINE_MUTEX(open_mutex); char *name; - fmode_t mode = 0; + fmode_t mode; int err; - int r = 0, w = 0, fd; + int r, w, fd; mode = file->f_mode & (FMODE_READ | FMODE_WRITE); if ((mode & HOSTFS_I(ino)->mode) == mode) @@ -308,12 +316,12 @@ static int hostfs_file_open(struct inode *ino, struct file *file) mode |= HOSTFS_I(ino)->mode; retry: + r = w = 0; + if (mode & FMODE_READ) r = 1; if (mode & FMODE_WRITE) - w = 1; - if (w) - r = 1; + r = w = 1; name = dentry_name(file->f_path.dentry); if (name == NULL) @@ -324,15 +332,16 @@ retry: if (fd < 0) return fd; - mutex_lock(&open_mutex); + mutex_lock(&HOSTFS_I(ino)->open_mutex); /* somebody else had handled it first? */ if ((mode & HOSTFS_I(ino)->mode) == mode) { - mutex_unlock(&open_mutex); + mutex_unlock(&HOSTFS_I(ino)->open_mutex); + close_file(&fd); return 0; } if ((mode | HOSTFS_I(ino)->mode) != mode) { mode |= HOSTFS_I(ino)->mode; - mutex_unlock(&open_mutex); + mutex_unlock(&HOSTFS_I(ino)->open_mutex); close_file(&fd); goto retry; } @@ -342,12 +351,12 @@ retry: err = replace_file(fd, HOSTFS_I(ino)->fd); close_file(&fd); if (err < 0) { - mutex_unlock(&open_mutex); + mutex_unlock(&HOSTFS_I(ino)->open_mutex); return err; } } HOSTFS_I(ino)->mode = mode; - mutex_unlock(&open_mutex); + mutex_unlock(&HOSTFS_I(ino)->open_mutex); return 0; } @@ -382,7 +391,7 @@ static const struct file_operations hostfs_file_fops = { .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, - .open = hostfs_file_open, + .open = hostfs_open, .release = hostfs_file_release, .fsync = hostfs_fsync, }; @@ -391,6 +400,8 @@ static const struct file_operations hostfs_dir_fops = { .llseek = generic_file_llseek, .iterate = hostfs_readdir, .read = generic_read_dir, + .open = hostfs_open, + .fsync = hostfs_fsync, }; static int hostfs_writepage(struct page *page, struct writeback_control *wbc) @@ -398,7 +409,7 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc) struct address_space *mapping = page->mapping; struct inode *inode = mapping->host; char *buffer; - unsigned long long base; + loff_t base = page_offset(page); int count = PAGE_CACHE_SIZE; int end_index = inode->i_size >> PAGE_CACHE_SHIFT; int err; @@ -407,7 +418,6 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc) count = inode->i_size & (PAGE_CACHE_SIZE-1); buffer = kmap(page); - base = ((unsigned long long) page->index) << PAGE_CACHE_SHIFT; err = write_file(HOSTFS_I(inode)->fd, &base, buffer, count); if (err != count) { @@ -432,26 +442,29 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc) static int hostfs_readpage(struct file *file, struct page *page) { char *buffer; - long long start; - int err = 0; + loff_t start = page_offset(page); + int bytes_read, ret = 0; - start = (long long) page->index << PAGE_CACHE_SHIFT; buffer = kmap(page); - err = read_file(FILE_HOSTFS_I(file)->fd, &start, buffer, + bytes_read = read_file(FILE_HOSTFS_I(file)->fd, &start, buffer, PAGE_CACHE_SIZE); - if (err < 0) + if (bytes_read < 0) { + ClearPageUptodate(page); + SetPageError(page); + ret = bytes_read; goto out; + } - memset(&buffer[err], 0, PAGE_CACHE_SIZE - err); + memset(buffer + bytes_read, 0, PAGE_CACHE_SIZE - bytes_read); - flush_dcache_page(page); + ClearPageError(page); SetPageUptodate(page); - if (PageError(page)) ClearPageError(page); - err = 0; + out: + flush_dcache_page(page); kunmap(page); unlock_page(page); - return err; + return ret; } static int hostfs_write_begin(struct file *file, struct address_space *mapping, @@ -528,11 +541,13 @@ static int read_name(struct inode *ino, char *name) init_special_inode(ino, st.mode & S_IFMT, rdev); ino->i_op = &hostfs_iops; break; - - default: + case S_IFREG: ino->i_op = &hostfs_iops; ino->i_fop = &hostfs_file_fops; ino->i_mapping->a_ops = &hostfs_aops; + break; + default: + return -EIO; } ino->i_ino = st.ino; @@ -566,10 +581,7 @@ static int hostfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, if (name == NULL) goto out_put; - fd = file_create(name, - mode & S_IRUSR, mode & S_IWUSR, mode & S_IXUSR, - mode & S_IRGRP, mode & S_IWGRP, mode & S_IXGRP, - mode & S_IROTH, mode & S_IWOTH, mode & S_IXOTH); + fd = file_create(name, mode & S_IFMT); if (fd < 0) error = fd; else |