Mercurial > hg > nginx
view src/os/unix/ngx_files.c @ 7668:0a04e5e4c40b
Large block sizes on Linux are now ignored (ticket #1168).
NFS on Linux is known to report wsize as a block size (in both f_bsize
and f_frsize, both in statfs() and statvfs()). On the other hand,
typical file system block sizes on Linux (ext2/ext3/ext4, XFS) are limited
to pagesize. (With FAT, block sizes can be at least up to 512k in
extreme cases, but this doesn't really matter, see below.)
To avoid too aggressive cache clearing on NFS volumes on Linux, block
sizes larger than pagesize are now ignored.
Note that it is safe to ignore large block sizes. Since 3899:e7cd13b7f759
(1.0.1) cache size is calculated based on fstat() st_blocks, and rounding
to file system block size is preserved mostly for Windows.
Note well that on other OSes valid block sizes seen are at least up
to 65536. In particular, UFS on FreeBSD is known to work well with block
and fragment sizes set to 65536.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 22 Jun 2020 18:02:58 +0300 |
parents | 577628e6b6a6 |
children | ccb5ff87ab3e |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #if (NGX_THREADS) #include <ngx_thread_pool.h> static void ngx_thread_read_handler(void *data, ngx_log_t *log); static void ngx_thread_write_chain_to_file_handler(void *data, ngx_log_t *log); #endif static ngx_chain_t *ngx_chain_to_iovec(ngx_iovec_t *vec, ngx_chain_t *cl); static ssize_t ngx_writev_file(ngx_file_t *file, ngx_iovec_t *vec, off_t offset); #if (NGX_HAVE_FILE_AIO) ngx_uint_t ngx_file_aio = 1; #endif ssize_t ngx_read_file(ngx_file_t *file, u_char *buf, size_t size, off_t offset) { ssize_t n; ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0, "read: %d, %p, %uz, %O", file->fd, buf, size, offset); #if (NGX_HAVE_PREAD) n = pread(file->fd, buf, size, offset); if (n == -1) { ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, "pread() \"%s\" failed", file->name.data); return NGX_ERROR; } #else if (file->sys_offset != offset) { if (lseek(file->fd, offset, SEEK_SET) == -1) { ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, "lseek() \"%s\" failed", file->name.data); return NGX_ERROR; } file->sys_offset = offset; } n = read(file->fd, buf, size); if (n == -1) { ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, "read() \"%s\" failed", file->name.data); return NGX_ERROR; } file->sys_offset += n; #endif file->offset += n; return n; } #if (NGX_THREADS) typedef struct { ngx_fd_t fd; ngx_uint_t write; /* unsigned write:1; */ u_char *buf; size_t size; ngx_chain_t *chain; off_t offset; size_t nbytes; ngx_err_t err; } ngx_thread_file_ctx_t; ssize_t ngx_thread_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset, ngx_pool_t *pool) { ngx_thread_task_t *task; ngx_thread_file_ctx_t *ctx; ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0, "thread read: %d, %p, %uz, %O", file->fd, buf, size, offset); task = file->thread_task; if (task == NULL) { task = ngx_thread_task_alloc(pool, sizeof(ngx_thread_file_ctx_t)); if (task == NULL) { return NGX_ERROR; } file->thread_task = task; } ctx = task->ctx; if (task->event.complete) { task->event.complete = 0; if (ctx->write) { ngx_log_error(NGX_LOG_ALERT, file->log, 0, "invalid thread call, read instead of write"); return NGX_ERROR; } if (ctx->err) { ngx_log_error(NGX_LOG_CRIT, file->log, ctx->err, "pread() \"%s\" failed", file->name.data); return NGX_ERROR; } return ctx->nbytes; } task->handler = ngx_thread_read_handler; ctx->write = 0; ctx->fd = file->fd; ctx->buf = buf; ctx->size = size; ctx->offset = offset; if (file->thread_handler(task, file) != NGX_OK) { return NGX_ERROR; } return NGX_AGAIN; } #if (NGX_HAVE_PREAD) static void ngx_thread_read_handler(void *data, ngx_log_t *log) { ngx_thread_file_ctx_t *ctx = data; ssize_t n; ngx_log_debug0(NGX_LOG_DEBUG_CORE, log, 0, "thread read handler"); n = pread(ctx->fd, ctx->buf, ctx->size, ctx->offset); if (n == -1) { ctx->err = ngx_errno; } else { ctx->nbytes = n; ctx->err = 0; } #if 0 ngx_time_update(); #endif ngx_log_debug4(NGX_LOG_DEBUG_CORE, log, 0, "pread: %z (err: %d) of %uz @%O", n, ctx->err, ctx->size, ctx->offset); } #else #error pread() is required! #endif #endif /* NGX_THREADS */ ssize_t ngx_write_file(ngx_file_t *file, u_char *buf, size_t size, off_t offset) { ssize_t n, written; ngx_err_t err; ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0, "write: %d, %p, %uz, %O", file->fd, buf, size, offset); written = 0; #if (NGX_HAVE_PWRITE) for ( ;; ) { n = pwrite(file->fd, buf + written, size, offset); if (n == -1) { err = ngx_errno; if (err == NGX_EINTR) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, file->log, err, "pwrite() was interrupted"); continue; } ngx_log_error(NGX_LOG_CRIT, file->log, err, "pwrite() \"%s\" failed", file->name.data); return NGX_ERROR; } file->offset += n; written += n; if ((size_t) n == size) { return written; } offset += n; size -= n; } #else if (file->sys_offset != offset) { if (lseek(file->fd, offset, SEEK_SET) == -1) { ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, "lseek() \"%s\" failed", file->name.data); return NGX_ERROR; } file->sys_offset = offset; } for ( ;; ) { n = write(file->fd, buf + written, size); if (n == -1) { err = ngx_errno; if (err == NGX_EINTR) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, file->log, err, "write() was interrupted"); continue; } ngx_log_error(NGX_LOG_CRIT, file->log, err, "write() \"%s\" failed", file->name.data); return NGX_ERROR; } file->sys_offset += n; file->offset += n; written += n; if ((size_t) n == size) { return written; } size -= n; } #endif } ngx_fd_t ngx_open_tempfile(u_char *name, ngx_uint_t persistent, ngx_uint_t access) { ngx_fd_t fd; fd = open((const char *) name, O_CREAT|O_EXCL|O_RDWR, access ? access : 0600); if (fd != -1 && !persistent) { (void) unlink((const char *) name); } return fd; } ssize_t ngx_write_chain_to_file(ngx_file_t *file, ngx_chain_t *cl, off_t offset, ngx_pool_t *pool) { ssize_t total, n; ngx_iovec_t vec; struct iovec iovs[NGX_IOVS_PREALLOCATE]; /* use pwrite() if there is the only buf in a chain */ if (cl->next == NULL) { return ngx_write_file(file, cl->buf->pos, (size_t) (cl->buf->last - cl->buf->pos), offset); } total = 0; vec.iovs = iovs; vec.nalloc = NGX_IOVS_PREALLOCATE; do { /* create the iovec and coalesce the neighbouring bufs */ cl = ngx_chain_to_iovec(&vec, cl); /* use pwrite() if there is the only iovec buffer */ if (vec.count == 1) { n = ngx_write_file(file, (u_char *) iovs[0].iov_base, iovs[0].iov_len, offset); if (n == NGX_ERROR) { return n; } return total + n; } n = ngx_writev_file(file, &vec, offset); if (n == NGX_ERROR) { return n; } offset += n; total += n; } while (cl); return total; } static ngx_chain_t * ngx_chain_to_iovec(ngx_iovec_t *vec, ngx_chain_t *cl) { size_t total, size; u_char *prev; ngx_uint_t n; struct iovec *iov; iov = NULL; prev = NULL; total = 0; n = 0; for ( /* void */ ; cl; cl = cl->next) { if (ngx_buf_special(cl->buf)) { continue; } size = cl->buf->last - cl->buf->pos; if (prev == cl->buf->pos) { iov->iov_len += size; } else { if (n == vec->nalloc) { break; } iov = &vec->iovs[n++]; iov->iov_base = (void *) cl->buf->pos; iov->iov_len = size; } prev = cl->buf->pos + size; total += size; } vec->count = n; vec->size = total; return cl; } static ssize_t ngx_writev_file(ngx_file_t *file, ngx_iovec_t *vec, off_t offset) { ssize_t n; ngx_err_t err; ngx_log_debug3(NGX_LOG_DEBUG_CORE, file->log, 0, "writev: %d, %uz, %O", file->fd, vec->size, offset); #if (NGX_HAVE_PWRITEV) eintr: n = pwritev(file->fd, vec->iovs, vec->count, offset); if (n == -1) { err = ngx_errno; if (err == NGX_EINTR) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, file->log, err, "pwritev() was interrupted"); goto eintr; } ngx_log_error(NGX_LOG_CRIT, file->log, err, "pwritev() \"%s\" failed", file->name.data); return NGX_ERROR; } if ((size_t) n != vec->size) { ngx_log_error(NGX_LOG_CRIT, file->log, 0, "pwritev() \"%s\" has written only %z of %uz", file->name.data, n, vec->size); return NGX_ERROR; } #else if (file->sys_offset != offset) { if (lseek(file->fd, offset, SEEK_SET) == -1) { ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, "lseek() \"%s\" failed", file->name.data); return NGX_ERROR; } file->sys_offset = offset; } eintr: n = writev(file->fd, vec->iovs, vec->count); if (n == -1) { err = ngx_errno; if (err == NGX_EINTR) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, file->log, err, "writev() was interrupted"); goto eintr; } ngx_log_error(NGX_LOG_CRIT, file->log, err, "writev() \"%s\" failed", file->name.data); return NGX_ERROR; } if ((size_t) n != vec->size) { ngx_log_error(NGX_LOG_CRIT, file->log, 0, "writev() \"%s\" has written only %z of %uz", file->name.data, n, vec->size); return NGX_ERROR; } file->sys_offset += n; #endif file->offset += n; return n; } #if (NGX_THREADS) ssize_t ngx_thread_write_chain_to_file(ngx_file_t *file, ngx_chain_t *cl, off_t offset, ngx_pool_t *pool) { ngx_thread_task_t *task; ngx_thread_file_ctx_t *ctx; ngx_log_debug3(NGX_LOG_DEBUG_CORE, file->log, 0, "thread write chain: %d, %p, %O", file->fd, cl, offset); task = file->thread_task; if (task == NULL) { task = ngx_thread_task_alloc(pool, sizeof(ngx_thread_file_ctx_t)); if (task == NULL) { return NGX_ERROR; } file->thread_task = task; } ctx = task->ctx; if (task->event.complete) { task->event.complete = 0; if (!ctx->write) { ngx_log_error(NGX_LOG_ALERT, file->log, 0, "invalid thread call, write instead of read"); return NGX_ERROR; } if (ctx->err || ctx->nbytes == 0) { ngx_log_error(NGX_LOG_CRIT, file->log, ctx->err, "pwritev() \"%s\" failed", file->name.data); return NGX_ERROR; } file->offset += ctx->nbytes; return ctx->nbytes; } task->handler = ngx_thread_write_chain_to_file_handler; ctx->write = 1; ctx->fd = file->fd; ctx->chain = cl; ctx->offset = offset; if (file->thread_handler(task, file) != NGX_OK) { return NGX_ERROR; } return NGX_AGAIN; } static void ngx_thread_write_chain_to_file_handler(void *data, ngx_log_t *log) { ngx_thread_file_ctx_t *ctx = data; #if (NGX_HAVE_PWRITEV) off_t offset; ssize_t n; ngx_err_t err; ngx_chain_t *cl; ngx_iovec_t vec; struct iovec iovs[NGX_IOVS_PREALLOCATE]; vec.iovs = iovs; vec.nalloc = NGX_IOVS_PREALLOCATE; cl = ctx->chain; offset = ctx->offset; ctx->nbytes = 0; ctx->err = 0; do { /* create the iovec and coalesce the neighbouring bufs */ cl = ngx_chain_to_iovec(&vec, cl); eintr: n = pwritev(ctx->fd, iovs, vec.count, offset); if (n == -1) { err = ngx_errno; if (err == NGX_EINTR) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, log, err, "pwritev() was interrupted"); goto eintr; } ctx->err = err; return; } if ((size_t) n != vec.size) { ctx->nbytes = 0; return; } ctx->nbytes += n; offset += n; } while (cl); #else ctx->err = NGX_ENOSYS; return; #endif } #endif /* NGX_THREADS */ ngx_int_t ngx_set_file_time(u_char *name, ngx_fd_t fd, time_t s) { struct timeval tv[2]; tv[0].tv_sec = ngx_time(); tv[0].tv_usec = 0; tv[1].tv_sec = s; tv[1].tv_usec = 0; if (utimes((char *) name, tv) != -1) { return NGX_OK; } return NGX_ERROR; } ngx_int_t ngx_create_file_mapping(ngx_file_mapping_t *fm) { fm->fd = ngx_open_file(fm->name, NGX_FILE_RDWR, NGX_FILE_TRUNCATE, NGX_FILE_DEFAULT_ACCESS); if (fm->fd == NGX_INVALID_FILE) { ngx_log_error(NGX_LOG_CRIT, fm->log, ngx_errno, ngx_open_file_n " \"%s\" failed", fm->name); return NGX_ERROR; } if (ftruncate(fm->fd, fm->size) == -1) { ngx_log_error(NGX_LOG_CRIT, fm->log, ngx_errno, "ftruncate() \"%s\" failed", fm->name); goto failed; } fm->addr = mmap(NULL, fm->size, PROT_READ|PROT_WRITE, MAP_SHARED, fm->fd, 0); if (fm->addr != MAP_FAILED) { return NGX_OK; } ngx_log_error(NGX_LOG_CRIT, fm->log, ngx_errno, "mmap(%uz) \"%s\" failed", fm->size, fm->name); failed: if (ngx_close_file(fm->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, fm->log, ngx_errno, ngx_close_file_n " \"%s\" failed", fm->name); } return NGX_ERROR; } void ngx_close_file_mapping(ngx_file_mapping_t *fm) { if (munmap(fm->addr, fm->size) == -1) { ngx_log_error(NGX_LOG_CRIT, fm->log, ngx_errno, "munmap(%uz) \"%s\" failed", fm->size, fm->name); } if (ngx_close_file(fm->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, fm->log, ngx_errno, ngx_close_file_n " \"%s\" failed", fm->name); } } ngx_int_t ngx_open_dir(ngx_str_t *name, ngx_dir_t *dir) { dir->dir = opendir((const char *) name->data); if (dir->dir == NULL) { return NGX_ERROR; } dir->valid_info = 0; return NGX_OK; } ngx_int_t ngx_read_dir(ngx_dir_t *dir) { dir->de = readdir(dir->dir); if (dir->de) { #if (NGX_HAVE_D_TYPE) dir->type = dir->de->d_type; #else dir->type = 0; #endif return NGX_OK; } return NGX_ERROR; } ngx_int_t ngx_open_glob(ngx_glob_t *gl) { int n; n = glob((char *) gl->pattern, 0, NULL, &gl->pglob); if (n == 0) { return NGX_OK; } #ifdef GLOB_NOMATCH if (n == GLOB_NOMATCH && gl->test) { return NGX_OK; } #endif return NGX_ERROR; } ngx_int_t ngx_read_glob(ngx_glob_t *gl, ngx_str_t *name) { size_t count; #ifdef GLOB_NOMATCH count = (size_t) gl->pglob.gl_pathc; #else count = (size_t) gl->pglob.gl_matchc; #endif if (gl->n < count) { name->len = (size_t) ngx_strlen(gl->pglob.gl_pathv[gl->n]); name->data = (u_char *) gl->pglob.gl_pathv[gl->n]; gl->n++; return NGX_OK; } return NGX_DONE; } void ngx_close_glob(ngx_glob_t *gl) { globfree(&gl->pglob); } ngx_err_t ngx_trylock_fd(ngx_fd_t fd) { struct flock fl; ngx_memzero(&fl, sizeof(struct flock)); fl.l_type = F_WRLCK; fl.l_whence = SEEK_SET; if (fcntl(fd, F_SETLK, &fl) == -1) { return ngx_errno; } return 0; } ngx_err_t ngx_lock_fd(ngx_fd_t fd) { struct flock fl; ngx_memzero(&fl, sizeof(struct flock)); fl.l_type = F_WRLCK; fl.l_whence = SEEK_SET; if (fcntl(fd, F_SETLKW, &fl) == -1) { return ngx_errno; } return 0; } ngx_err_t ngx_unlock_fd(ngx_fd_t fd) { struct flock fl; ngx_memzero(&fl, sizeof(struct flock)); fl.l_type = F_UNLCK; fl.l_whence = SEEK_SET; if (fcntl(fd, F_SETLK, &fl) == -1) { return ngx_errno; } return 0; } #if (NGX_HAVE_POSIX_FADVISE) && !(NGX_HAVE_F_READAHEAD) ngx_int_t ngx_read_ahead(ngx_fd_t fd, size_t n) { int err; err = posix_fadvise(fd, 0, 0, POSIX_FADV_SEQUENTIAL); if (err == 0) { return 0; } ngx_set_errno(err); return NGX_FILE_ERROR; } #endif #if (NGX_HAVE_O_DIRECT) ngx_int_t ngx_directio_on(ngx_fd_t fd) { int flags; flags = fcntl(fd, F_GETFL); if (flags == -1) { return NGX_FILE_ERROR; } return fcntl(fd, F_SETFL, flags | O_DIRECT); } ngx_int_t ngx_directio_off(ngx_fd_t fd) { int flags; flags = fcntl(fd, F_GETFL); if (flags == -1) { return NGX_FILE_ERROR; } return fcntl(fd, F_SETFL, flags & ~O_DIRECT); } #endif #if (NGX_HAVE_STATFS) size_t ngx_fs_bsize(u_char *name) { struct statfs fs; if (statfs((char *) name, &fs) == -1) { return 512; } if ((fs.f_bsize % 512) != 0) { return 512; } #if (NGX_LINUX) if ((size_t) fs.f_bsize > ngx_pagesize) { return 512; } #endif return (size_t) fs.f_bsize; } #elif (NGX_HAVE_STATVFS) size_t ngx_fs_bsize(u_char *name) { struct statvfs fs; if (statvfs((char *) name, &fs) == -1) { return 512; } if ((fs.f_frsize % 512) != 0) { return 512; } #if (NGX_LINUX) if ((size_t) fs.f_frsize > ngx_pagesize) { return 512; } #endif return (size_t) fs.f_frsize; } #else size_t ngx_fs_bsize(u_char *name) { return 512; } #endif