Mercurial > hg > nginx-quic
view src/core/ngx_output_chain.c @ 8743:5d09596909c6 stable-1.20
Upstream: fixed timeouts with gRPC, SSL and select (ticket #2229).
With SSL it is possible that an established connection is ready for
reading after the handshake. Further, events might be already disabled
in case of level-triggered event methods. If this happens and
ngx_http_upstream_send_request() blocks waiting for some data from
the upstream, such as flow control in case of gRPC, the connection
will time out due to no read events on the upstream connection.
Fix is to explicitly check the c->read->ready flag if sending request
blocks and post a read event if it is set.
Note that while it is possible to modify ngx_ssl_handshake() to keep
read events active, this won't completely resolve the issue, since
there can be data already received during the SSL handshake
(see 573bd30e46b4).
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Fri, 20 Aug 2021 03:53:56 +0300 |
parents | a7ff19afbb14 |
children | 862f6130d357 |
line wrap: on
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #if 0 #define NGX_SENDFILE_LIMIT 4096 #endif /* * When DIRECTIO is enabled FreeBSD, Solaris, and MacOSX read directly * to an application memory from a device if parameters are aligned * to device sector boundary (512 bytes). They fallback to usual read * operation if the parameters are not aligned. * Linux allows DIRECTIO only if the parameters are aligned to a filesystem * sector boundary, otherwise it returns EINVAL. The sector size is * usually 512 bytes, however, on XFS it may be 4096 bytes. */ #define NGX_NONE 1 static ngx_inline ngx_int_t ngx_output_chain_as_is(ngx_output_chain_ctx_t *ctx, ngx_buf_t *buf); #if (NGX_HAVE_AIO_SENDFILE) static ngx_int_t ngx_output_chain_aio_setup(ngx_output_chain_ctx_t *ctx, ngx_file_t *file); #endif static ngx_int_t ngx_output_chain_add_copy(ngx_pool_t *pool, ngx_chain_t **chain, ngx_chain_t *in); static ngx_int_t ngx_output_chain_align_file_buf(ngx_output_chain_ctx_t *ctx, off_t bsize); static ngx_int_t ngx_output_chain_get_buf(ngx_output_chain_ctx_t *ctx, off_t bsize); static ngx_int_t ngx_output_chain_copy_buf(ngx_output_chain_ctx_t *ctx); ngx_int_t ngx_output_chain(ngx_output_chain_ctx_t *ctx, ngx_chain_t *in) { off_t bsize; ngx_int_t rc, last; ngx_chain_t *cl, *out, **last_out; if (ctx->in == NULL && ctx->busy == NULL #if (NGX_HAVE_FILE_AIO || NGX_THREADS) && !ctx->aio #endif ) { /* * the short path for the case when the ctx->in and ctx->busy chains * are empty, the incoming chain is empty too or has the single buf * that does not require the copy */ if (in == NULL) { return ctx->output_filter(ctx->filter_ctx, in); } if (in->next == NULL #if (NGX_SENDFILE_LIMIT) && !(in->buf->in_file && in->buf->file_last > NGX_SENDFILE_LIMIT) #endif && ngx_output_chain_as_is(ctx, in->buf)) { return ctx->output_filter(ctx->filter_ctx, in); } } /* add the incoming buf to the chain ctx->in */ if (in) { if (ngx_output_chain_add_copy(ctx->pool, &ctx->in, in) == NGX_ERROR) { return NGX_ERROR; } } out = NULL; last_out = &out; last = NGX_NONE; for ( ;; ) { #if (NGX_HAVE_FILE_AIO || NGX_THREADS) if (ctx->aio) { return NGX_AGAIN; } #endif while (ctx->in) { /* * cycle while there are the ctx->in bufs * and there are the free output bufs to copy in */ bsize = ngx_buf_size(ctx->in->buf); if (bsize == 0 && !ngx_buf_special(ctx->in->buf)) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, 0, "zero size buf in output " "t:%d r:%d f:%d %p %p-%p %p %O-%O", ctx->in->buf->temporary, ctx->in->buf->recycled, ctx->in->buf->in_file, ctx->in->buf->start, ctx->in->buf->pos, ctx->in->buf->last, ctx->in->buf->file, ctx->in->buf->file_pos, ctx->in->buf->file_last); ngx_debug_point(); ctx->in = ctx->in->next; continue; } if (bsize < 0) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, 0, "negative size buf in output " "t:%d r:%d f:%d %p %p-%p %p %O-%O", ctx->in->buf->temporary, ctx->in->buf->recycled, ctx->in->buf->in_file, ctx->in->buf->start, ctx->in->buf->pos, ctx->in->buf->last, ctx->in->buf->file, ctx->in->buf->file_pos, ctx->in->buf->file_last); ngx_debug_point(); return NGX_ERROR; } if (ngx_output_chain_as_is(ctx, ctx->in->buf)) { /* move the chain link to the output chain */ cl = ctx->in; ctx->in = cl->next; *last_out = cl; last_out = &cl->next; cl->next = NULL; continue; } if (ctx->buf == NULL) { rc = ngx_output_chain_align_file_buf(ctx, bsize); if (rc == NGX_ERROR) { return NGX_ERROR; } if (rc != NGX_OK) { if (ctx->free) { /* get the free buf */ cl = ctx->free; ctx->buf = cl->buf; ctx->free = cl->next; ngx_free_chain(ctx->pool, cl); } else if (out || ctx->allocated == ctx->bufs.num) { break; } else if (ngx_output_chain_get_buf(ctx, bsize) != NGX_OK) { return NGX_ERROR; } } } rc = ngx_output_chain_copy_buf(ctx); if (rc == NGX_ERROR) { return rc; } if (rc == NGX_AGAIN) { if (out) { break; } return rc; } /* delete the completed buf from the ctx->in chain */ if (ngx_buf_size(ctx->in->buf) == 0) { ctx->in = ctx->in->next; } cl = ngx_alloc_chain_link(ctx->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = ctx->buf; cl->next = NULL; *last_out = cl; last_out = &cl->next; ctx->buf = NULL; } if (out == NULL && last != NGX_NONE) { if (ctx->in) { return NGX_AGAIN; } return last; } last = ctx->output_filter(ctx->filter_ctx, out); if (last == NGX_ERROR || last == NGX_DONE) { return last; } ngx_chain_update_chains(ctx->pool, &ctx->free, &ctx->busy, &out, ctx->tag); last_out = &out; } } static ngx_inline ngx_int_t ngx_output_chain_as_is(ngx_output_chain_ctx_t *ctx, ngx_buf_t *buf) { ngx_uint_t sendfile; if (ngx_buf_special(buf)) { return 1; } #if (NGX_THREADS) if (buf->in_file) { buf->file->thread_handler = ctx->thread_handler; buf->file->thread_ctx = ctx->filter_ctx; } #endif if (buf->in_file && buf->file->directio) { return 0; } sendfile = ctx->sendfile; #if (NGX_SENDFILE_LIMIT) if (buf->in_file && buf->file_pos >= NGX_SENDFILE_LIMIT) { sendfile = 0; } #endif if (!sendfile) { if (!ngx_buf_in_memory(buf)) { return 0; } buf->in_file = 0; } #if (NGX_HAVE_AIO_SENDFILE) if (ctx->aio_preload && buf->in_file) { (void) ngx_output_chain_aio_setup(ctx, buf->file); } #endif if (ctx->need_in_memory && !ngx_buf_in_memory(buf)) { return 0; } if (ctx->need_in_temp && (buf->memory || buf->mmap)) { return 0; } return 1; } #if (NGX_HAVE_AIO_SENDFILE) static ngx_int_t ngx_output_chain_aio_setup(ngx_output_chain_ctx_t *ctx, ngx_file_t *file) { ngx_event_aio_t *aio; if (file->aio == NULL && ngx_file_aio_init(file, ctx->pool) != NGX_OK) { return NGX_ERROR; } aio = file->aio; aio->data = ctx->filter_ctx; aio->preload_handler = ctx->aio_preload; return NGX_OK; } #endif static ngx_int_t ngx_output_chain_add_copy(ngx_pool_t *pool, ngx_chain_t **chain, ngx_chain_t *in) { ngx_chain_t *cl, **ll; #if (NGX_SENDFILE_LIMIT) ngx_buf_t *b, *buf; #endif ll = chain; for (cl = *chain; cl; cl = cl->next) { ll = &cl->next; } while (in) { cl = ngx_alloc_chain_link(pool); if (cl == NULL) { return NGX_ERROR; } #if (NGX_SENDFILE_LIMIT) buf = in->buf; if (buf->in_file && buf->file_pos < NGX_SENDFILE_LIMIT && buf->file_last > NGX_SENDFILE_LIMIT) { /* split a file buf on two bufs by the sendfile limit */ b = ngx_calloc_buf(pool); if (b == NULL) { return NGX_ERROR; } ngx_memcpy(b, buf, sizeof(ngx_buf_t)); if (ngx_buf_in_memory(buf)) { buf->pos += (ssize_t) (NGX_SENDFILE_LIMIT - buf->file_pos); b->last = buf->pos; } buf->file_pos = NGX_SENDFILE_LIMIT; b->file_last = NGX_SENDFILE_LIMIT; cl->buf = b; } else { cl->buf = buf; in = in->next; } #else cl->buf = in->buf; in = in->next; #endif cl->next = NULL; *ll = cl; ll = &cl->next; } return NGX_OK; } static ngx_int_t ngx_output_chain_align_file_buf(ngx_output_chain_ctx_t *ctx, off_t bsize) { size_t size; ngx_buf_t *in; in = ctx->in->buf; if (in->file == NULL || !in->file->directio) { return NGX_DECLINED; } ctx->directio = 1; size = (size_t) (in->file_pos - (in->file_pos & ~(ctx->alignment - 1))); if (size == 0) { if (bsize >= (off_t) ctx->bufs.size) { return NGX_DECLINED; } size = (size_t) bsize; } else { size = (size_t) ctx->alignment - size; if ((off_t) size > bsize) { size = (size_t) bsize; } } ctx->buf = ngx_create_temp_buf(ctx->pool, size); if (ctx->buf == NULL) { return NGX_ERROR; } /* * we do not set ctx->buf->tag, because we do not want * to reuse the buf via ctx->free list */ #if (NGX_HAVE_ALIGNED_DIRECTIO) ctx->unaligned = 1; #endif return NGX_OK; } static ngx_int_t ngx_output_chain_get_buf(ngx_output_chain_ctx_t *ctx, off_t bsize) { size_t size; ngx_buf_t *b, *in; ngx_uint_t recycled; in = ctx->in->buf; size = ctx->bufs.size; recycled = 1; if (in->last_in_chain) { if (bsize < (off_t) size) { /* * allocate a small temp buf for a small last buf * or its small last part */ size = (size_t) bsize; recycled = 0; } else if (!ctx->directio && ctx->bufs.num == 1 && (bsize < (off_t) (size + size / 4))) { /* * allocate a temp buf that equals to a last buf, * if there is no directio, the last buf size is lesser * than 1.25 of bufs.size and the temp buf is single */ size = (size_t) bsize; recycled = 0; } } b = ngx_calloc_buf(ctx->pool); if (b == NULL) { return NGX_ERROR; } if (ctx->directio) { /* * allocate block aligned to a disk sector size to enable * userland buffer direct usage conjunctly with directio */ b->start = ngx_pmemalign(ctx->pool, size, (size_t) ctx->alignment); if (b->start == NULL) { return NGX_ERROR; } } else { b->start = ngx_palloc(ctx->pool, size); if (b->start == NULL) { return NGX_ERROR; } } b->pos = b->start; b->last = b->start; b->end = b->last + size; b->temporary = 1; b->tag = ctx->tag; b->recycled = recycled; ctx->buf = b; ctx->allocated++; return NGX_OK; } static ngx_int_t ngx_output_chain_copy_buf(ngx_output_chain_ctx_t *ctx) { off_t size; ssize_t n; ngx_buf_t *src, *dst; ngx_uint_t sendfile; src = ctx->in->buf; dst = ctx->buf; size = ngx_buf_size(src); size = ngx_min(size, dst->end - dst->pos); sendfile = ctx->sendfile && !ctx->directio; #if (NGX_SENDFILE_LIMIT) if (src->in_file && src->file_pos >= NGX_SENDFILE_LIMIT) { sendfile = 0; } #endif if (ngx_buf_in_memory(src)) { ngx_memcpy(dst->pos, src->pos, (size_t) size); src->pos += (size_t) size; dst->last += (size_t) size; if (src->in_file) { if (sendfile) { dst->in_file = 1; dst->file = src->file; dst->file_pos = src->file_pos; dst->file_last = src->file_pos + size; } else { dst->in_file = 0; } src->file_pos += size; } else { dst->in_file = 0; } if (src->pos == src->last) { dst->flush = src->flush; dst->last_buf = src->last_buf; dst->last_in_chain = src->last_in_chain; } } else { #if (NGX_HAVE_ALIGNED_DIRECTIO) if (ctx->unaligned) { if (ngx_directio_off(src->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, ngx_errno, ngx_directio_off_n " \"%s\" failed", src->file->name.data); } } #endif #if (NGX_HAVE_FILE_AIO) if (ctx->aio_handler) { n = ngx_file_aio_read(src->file, dst->pos, (size_t) size, src->file_pos, ctx->pool); if (n == NGX_AGAIN) { ctx->aio_handler(ctx, src->file); return NGX_AGAIN; } } else #endif #if (NGX_THREADS) if (ctx->thread_handler) { src->file->thread_task = ctx->thread_task; src->file->thread_handler = ctx->thread_handler; src->file->thread_ctx = ctx->filter_ctx; n = ngx_thread_read(src->file, dst->pos, (size_t) size, src->file_pos, ctx->pool); if (n == NGX_AGAIN) { ctx->thread_task = src->file->thread_task; return NGX_AGAIN; } } else #endif { n = ngx_read_file(src->file, dst->pos, (size_t) size, src->file_pos); } #if (NGX_HAVE_ALIGNED_DIRECTIO) if (ctx->unaligned) { ngx_err_t err; err = ngx_errno; if (ngx_directio_on(src->file->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, ngx_errno, ngx_directio_on_n " \"%s\" failed", src->file->name.data); } ngx_set_errno(err); ctx->unaligned = 0; } #endif if (n == NGX_ERROR) { return (ngx_int_t) n; } if (n != size) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, 0, ngx_read_file_n " read only %z of %O from \"%s\"", n, size, src->file->name.data); return NGX_ERROR; } dst->last += n; if (sendfile) { dst->in_file = 1; dst->file = src->file; dst->file_pos = src->file_pos; dst->file_last = src->file_pos + n; } else { dst->in_file = 0; } src->file_pos += n; if (src->file_pos == src->file_last) { dst->flush = src->flush; dst->last_buf = src->last_buf; dst->last_in_chain = src->last_in_chain; } } return NGX_OK; } ngx_int_t ngx_chain_writer(void *data, ngx_chain_t *in) { ngx_chain_writer_ctx_t *ctx = data; off_t size; ngx_chain_t *cl, *ln, *chain; ngx_connection_t *c; c = ctx->connection; for (size = 0; in; in = in->next) { if (ngx_buf_size(in->buf) == 0 && !ngx_buf_special(in->buf)) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, 0, "zero size buf in chain writer " "t:%d r:%d f:%d %p %p-%p %p %O-%O", in->buf->temporary, in->buf->recycled, in->buf->in_file, in->buf->start, in->buf->pos, in->buf->last, in->buf->file, in->buf->file_pos, in->buf->file_last); ngx_debug_point(); continue; } if (ngx_buf_size(in->buf) < 0) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, 0, "negative size buf in chain writer " "t:%d r:%d f:%d %p %p-%p %p %O-%O", in->buf->temporary, in->buf->recycled, in->buf->in_file, in->buf->start, in->buf->pos, in->buf->last, in->buf->file, in->buf->file_pos, in->buf->file_last); ngx_debug_point(); return NGX_ERROR; } size += ngx_buf_size(in->buf); ngx_log_debug2(NGX_LOG_DEBUG_CORE, c->log, 0, "chain writer buf fl:%d s:%uO", in->buf->flush, ngx_buf_size(in->buf)); cl = ngx_alloc_chain_link(ctx->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = in->buf; cl->next = NULL; *ctx->last = cl; ctx->last = &cl->next; } ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "chain writer in: %p", ctx->out); for (cl = ctx->out; cl; cl = cl->next) { if (ngx_buf_size(cl->buf) == 0 && !ngx_buf_special(cl->buf)) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, 0, "zero size buf in chain writer " "t:%d r:%d f:%d %p %p-%p %p %O-%O", cl->buf->temporary, cl->buf->recycled, cl->buf->in_file, cl->buf->start, cl->buf->pos, cl->buf->last, cl->buf->file, cl->buf->file_pos, cl->buf->file_last); ngx_debug_point(); continue; } if (ngx_buf_size(cl->buf) < 0) { ngx_log_error(NGX_LOG_ALERT, ctx->pool->log, 0, "negative size buf in chain writer " "t:%d r:%d f:%d %p %p-%p %p %O-%O", cl->buf->temporary, cl->buf->recycled, cl->buf->in_file, cl->buf->start, cl->buf->pos, cl->buf->last, cl->buf->file, cl->buf->file_pos, cl->buf->file_last); ngx_debug_point(); return NGX_ERROR; } size += ngx_buf_size(cl->buf); } if (size == 0 && !c->buffered) { return NGX_OK; } chain = c->send_chain(c, ctx->out, ctx->limit); ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "chain writer out: %p", chain); if (chain == NGX_CHAIN_ERROR) { return NGX_ERROR; } for (cl = ctx->out; cl && cl != chain; /* void */) { ln = cl; cl = cl->next; ngx_free_chain(ctx->pool, ln); } ctx->out = chain; if (ctx->out == NULL) { ctx->last = &ctx->out; if (!c->buffered) { return NGX_OK; } } return NGX_AGAIN; }