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([71.212.142.129]) by smtp.gmail.com with ESMTPSA id h8-20020a654808000000b003f9d1c020cbsm306369pgs.51.2022.05.20.17.04.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 May 2022 17:04:10 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, alex.bennee@linaro.org Subject: [PATCH v3 07/49] semihosting: Split out guestfd.c Date: Fri, 20 May 2022 17:03:18 -0700 Message-Id: <20220521000400.454525-8-richard.henderson@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220521000400.454525-1-richard.henderson@linaro.org> References: <20220521000400.454525-1-richard.henderson@linaro.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::529; envelope-from=richard.henderson@linaro.org; helo=mail-pg1-x529.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patch=linaro.org@nongnu.org Sender: "Qemu-devel" In arm-compat-semi.c, we have more advanced treatment of guest file descriptors than we do in other implementations. Split out GuestFD and related functions to a new file so that they can be shared. Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson --- configs/targets/aarch64-linux-user.mak | 1 + configs/targets/aarch64_be-linux-user.mak | 1 + configs/targets/arm-linux-user.mak | 1 + configs/targets/armeb-linux-user.mak | 1 + configs/targets/riscv32-linux-user.mak | 1 + configs/targets/riscv64-linux-user.mak | 1 + include/semihosting/guestfd.h | 83 +++++++++++ semihosting/arm-compat-semi.c | 164 +++------------------- semihosting/guestfd.c | 118 ++++++++++++++++ semihosting/meson.build | 4 + 10 files changed, 233 insertions(+), 142 deletions(-) create mode 100644 include/semihosting/guestfd.h create mode 100644 semihosting/guestfd.c diff --git a/configs/targets/aarch64-linux-user.mak b/configs/targets/aarch64-linux-user.mak index d0c603c54e..db552f1839 100644 --- a/configs/targets/aarch64-linux-user.mak +++ b/configs/targets/aarch64-linux-user.mak @@ -2,4 +2,5 @@ TARGET_ARCH=aarch64 TARGET_BASE_ARCH=arm TARGET_XML_FILES= gdb-xml/aarch64-core.xml gdb-xml/aarch64-fpu.xml TARGET_HAS_BFLT=y +CONFIG_SEMIHOSTING=y CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y diff --git a/configs/targets/aarch64_be-linux-user.mak b/configs/targets/aarch64_be-linux-user.mak index 7794424745..dc78044fb1 100644 --- a/configs/targets/aarch64_be-linux-user.mak +++ b/configs/targets/aarch64_be-linux-user.mak @@ -3,4 +3,5 @@ TARGET_BASE_ARCH=arm TARGET_BIG_ENDIAN=y TARGET_XML_FILES= gdb-xml/aarch64-core.xml gdb-xml/aarch64-fpu.xml TARGET_HAS_BFLT=y +CONFIG_SEMIHOSTING=y CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y diff --git a/configs/targets/arm-linux-user.mak b/configs/targets/arm-linux-user.mak index 3e10d6b15d..7f5d65794c 100644 --- a/configs/targets/arm-linux-user.mak +++ b/configs/targets/arm-linux-user.mak @@ -3,4 +3,5 @@ TARGET_SYSTBL_ABI=common,oabi TARGET_SYSTBL=syscall.tbl TARGET_XML_FILES= gdb-xml/arm-core.xml gdb-xml/arm-vfp.xml gdb-xml/arm-vfp3.xml gdb-xml/arm-vfp-sysregs.xml gdb-xml/arm-neon.xml gdb-xml/arm-m-profile.xml gdb-xml/arm-m-profile-mve.xml TARGET_HAS_BFLT=y +CONFIG_SEMIHOSTING=y CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y diff --git a/configs/targets/armeb-linux-user.mak b/configs/targets/armeb-linux-user.mak index a249cc2e29..943d0d87bf 100644 --- a/configs/targets/armeb-linux-user.mak +++ b/configs/targets/armeb-linux-user.mak @@ -4,4 +4,5 @@ TARGET_SYSTBL=syscall.tbl TARGET_BIG_ENDIAN=y TARGET_XML_FILES= gdb-xml/arm-core.xml gdb-xml/arm-vfp.xml gdb-xml/arm-vfp3.xml gdb-xml/arm-vfp-sysregs.xml gdb-xml/arm-neon.xml gdb-xml/arm-m-profile.xml gdb-xml/arm-m-profile-mve.xml TARGET_HAS_BFLT=y +CONFIG_SEMIHOSTING=y CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y diff --git a/configs/targets/riscv32-linux-user.mak b/configs/targets/riscv32-linux-user.mak index bd2f1fd497..9761618e67 100644 --- a/configs/targets/riscv32-linux-user.mak +++ b/configs/targets/riscv32-linux-user.mak @@ -2,4 +2,5 @@ TARGET_ARCH=riscv32 TARGET_BASE_ARCH=riscv TARGET_ABI_DIR=riscv TARGET_XML_FILES= gdb-xml/riscv-32bit-cpu.xml gdb-xml/riscv-32bit-fpu.xml gdb-xml/riscv-64bit-fpu.xml gdb-xml/riscv-32bit-virtual.xml +CONFIG_SEMIHOSTING=y CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y diff --git a/configs/targets/riscv64-linux-user.mak b/configs/targets/riscv64-linux-user.mak index 4aca7662ce..cfd1fd382f 100644 --- a/configs/targets/riscv64-linux-user.mak +++ b/configs/targets/riscv64-linux-user.mak @@ -2,4 +2,5 @@ TARGET_ARCH=riscv64 TARGET_BASE_ARCH=riscv TARGET_ABI_DIR=riscv TARGET_XML_FILES= gdb-xml/riscv-64bit-cpu.xml gdb-xml/riscv-32bit-fpu.xml gdb-xml/riscv-64bit-fpu.xml gdb-xml/riscv-64bit-virtual.xml +CONFIG_SEMIHOSTING=y CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y diff --git a/include/semihosting/guestfd.h b/include/semihosting/guestfd.h new file mode 100644 index 0000000000..ef268abe85 --- /dev/null +++ b/include/semihosting/guestfd.h @@ -0,0 +1,83 @@ +/* + * Hosted file support for semihosting syscalls. + * + * Copyright (c) 2005, 2007 CodeSourcery. + * Copyright (c) 2019 Linaro + * Copyright © 2020 by Keith Packard + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#ifndef SEMIHOSTING_GUESTFD_H +#define SEMIHOSTING_GUESTFD_H + +typedef enum GuestFDType { + GuestFDUnused = 0, + GuestFDHost = 1, + GuestFDGDB = 2, + GuestFDStatic = 3, +} GuestFDType; + +/* + * Guest file descriptors are integer indexes into an array of + * these structures (we will dynamically resize as necessary). + */ +typedef struct GuestFD { + GuestFDType type; + union { + int hostfd; + struct { + const uint8_t *data; + size_t len; + size_t off; + } staticfile; + }; +} GuestFD; + +/** + * alloc_guestfd: + * + * Allocate an unused GuestFD index. The associated guestfd index + * will still be GuestFDUnused until it is initialized. + */ +int alloc_guestfd(void); + +/** + * dealloc_guestfd: + * @guestfd: GuestFD index + * + * Deallocate a GuestFD index. The associated GuestFD structure + * will be recycled for a subsequent allocation. + */ +void dealloc_guestfd(int guestfd); + +/** + * get_guestfd: + * @guestfd: GuestFD index + * + * Return the GuestFD structure associated with an initialized @guestfd, + * or NULL if it has not been allocated, or hasn't been initialized. + */ +GuestFD *get_guestfd(int guestfd); + +/** + * associate_guestfd: + * @guestfd: GuestFD index + * @hostfd: host file descriptor + * + * Initialize the GuestFD for @guestfd to GuestFDHost using @hostfd. + */ +void associate_guestfd(int guestfd, int hostfd); + +/** + * staticfile_guestfd: + * @guestfd: GuestFD index + * @data: data to be read + * @len: length of @data + * + * Initialize the GuestFD for @guestfd to GuestFDStatic. + * The @len bytes at @data will be returned to the guest on reads. + */ +void staticfile_guestfd(int guestfd, const uint8_t *data, size_t len); + +#endif /* SEMIHOSTING_GUESTFD_H */ diff --git a/semihosting/arm-compat-semi.c b/semihosting/arm-compat-semi.c index dbef280b87..c6bfd4d1ba 100644 --- a/semihosting/arm-compat-semi.c +++ b/semihosting/arm-compat-semi.c @@ -32,12 +32,13 @@ */ #include "qemu/osdep.h" - #include "semihosting/semihost.h" #include "semihosting/console.h" #include "semihosting/common-semi.h" +#include "semihosting/guestfd.h" #include "qemu/timer.h" #include "exec/gdbstub.h" + #ifdef CONFIG_USER_ONLY #include "qemu.h" @@ -123,27 +124,6 @@ static int open_modeflags[12] = { O_RDWR | O_CREAT | O_APPEND | O_BINARY }; -typedef enum GuestFDType { - GuestFDUnused = 0, - GuestFDHost = 1, - GuestFDGDB = 2, - GuestFDFeatureFile = 3, -} GuestFDType; - -/* - * Guest file descriptors are integer indexes into an array of - * these structures (we will dynamically resize as necessary). - */ -typedef struct GuestFD { - GuestFDType type; - union { - int hostfd; - target_ulong featurefile_offset; - }; -} GuestFD; - -static GArray *guestfd_array; - #ifndef CONFIG_USER_ONLY /** @@ -268,98 +248,6 @@ common_semi_sys_exit_extended(CPUState *cs, int nr) #endif -/* - * Allocate a new guest file descriptor and return it; if we - * couldn't allocate a new fd then return -1. - * This is a fairly simplistic implementation because we don't - * expect that most semihosting guest programs will make very - * heavy use of opening and closing fds. - */ -static int alloc_guestfd(void) -{ - guint i; - - if (!guestfd_array) { - /* New entries zero-initialized, i.e. type GuestFDUnused */ - guestfd_array = g_array_new(FALSE, TRUE, sizeof(GuestFD)); - } - - /* SYS_OPEN should return nonzero handle on success. Start guestfd from 1 */ - for (i = 1; i < guestfd_array->len; i++) { - GuestFD *gf = &g_array_index(guestfd_array, GuestFD, i); - - if (gf->type == GuestFDUnused) { - return i; - } - } - - /* All elements already in use: expand the array */ - g_array_set_size(guestfd_array, i + 1); - return i; -} - -/* - * Look up the guestfd in the data structure; return NULL - * for out of bounds, but don't check whether the slot is unused. - * This is used internally by the other guestfd functions. - */ -static GuestFD *do_get_guestfd(int guestfd) -{ - if (!guestfd_array) { - return NULL; - } - - if (guestfd <= 0 || guestfd >= guestfd_array->len) { - return NULL; - } - - return &g_array_index(guestfd_array, GuestFD, guestfd); -} - -/* - * Associate the specified guest fd (which must have been - * allocated via alloc_fd() and not previously used) with - * the specified host/gdb fd. - */ -static void associate_guestfd(int guestfd, int hostfd) -{ - GuestFD *gf = do_get_guestfd(guestfd); - - assert(gf); - gf->type = use_gdb_syscalls() ? GuestFDGDB : GuestFDHost; - gf->hostfd = hostfd; -} - -/* - * Deallocate the specified guest file descriptor. This doesn't - * close the host fd, it merely undoes the work of alloc_fd(). - */ -static void dealloc_guestfd(int guestfd) -{ - GuestFD *gf = do_get_guestfd(guestfd); - - assert(gf); - gf->type = GuestFDUnused; -} - -/* - * Given a guest file descriptor, get the associated struct. - * If the fd is not valid, return NULL. This is the function - * used by the various semihosting calls to validate a handle - * from the guest. - * Note: calling alloc_guestfd() or dealloc_guestfd() will - * invalidate any GuestFD* obtained by calling this function. - */ -static GuestFD *get_guestfd(int guestfd) -{ - GuestFD *gf = do_get_guestfd(guestfd); - - if (!gf || gf->type == GuestFDUnused) { - return NULL; - } - return gf; -} - /* * The semihosting API has no concept of its errno being thread-safe, * as the API design predates SMP CPUs and was intended as a simple @@ -665,22 +553,13 @@ static const uint8_t featurefile_data[] = { SH_EXT_EXIT_EXTENDED | SH_EXT_STDOUT_STDERR, /* Feature byte 0 */ }; -static void init_featurefile_guestfd(int guestfd) -{ - GuestFD *gf = do_get_guestfd(guestfd); - - assert(gf); - gf->type = GuestFDFeatureFile; - gf->featurefile_offset = 0; -} - -static uint32_t featurefile_closefn(CPUState *cs, GuestFD *gf) +static uint32_t staticfile_closefn(CPUState *cs, GuestFD *gf) { /* Nothing to do */ return 0; } -static uint32_t featurefile_writefn(CPUState *cs, GuestFD *gf, +static uint32_t staticfile_writefn(CPUState *cs, GuestFD *gf, target_ulong buf, uint32_t len) { /* This fd can never be open for writing */ @@ -689,7 +568,7 @@ static uint32_t featurefile_writefn(CPUState *cs, GuestFD *gf, return set_swi_errno(cs, -1); } -static uint32_t featurefile_readfn(CPUState *cs, GuestFD *gf, +static uint32_t staticfile_readfn(CPUState *cs, GuestFD *gf, target_ulong buf, uint32_t len) { CPUArchState *env = cs->env_ptr; @@ -703,11 +582,11 @@ static uint32_t featurefile_readfn(CPUState *cs, GuestFD *gf, } for (i = 0; i < len; i++) { - if (gf->featurefile_offset >= sizeof(featurefile_data)) { + if (gf->staticfile.off >= gf->staticfile.len) { break; } - s[i] = featurefile_data[gf->featurefile_offset]; - gf->featurefile_offset++; + s[i] = gf->staticfile.data[gf->staticfile.off]; + gf->staticfile.off++; } unlock_user(s, buf, len); @@ -716,21 +595,21 @@ static uint32_t featurefile_readfn(CPUState *cs, GuestFD *gf, return len - i; } -static uint32_t featurefile_isattyfn(CPUState *cs, GuestFD *gf) +static uint32_t staticfile_isattyfn(CPUState *cs, GuestFD *gf) { return 0; } -static uint32_t featurefile_seekfn(CPUState *cs, GuestFD *gf, +static uint32_t staticfile_seekfn(CPUState *cs, GuestFD *gf, target_ulong offset) { - gf->featurefile_offset = offset; + gf->staticfile.off = offset; return 0; } -static uint32_t featurefile_flenfn(CPUState *cs, GuestFD *gf) +static uint32_t staticfile_flenfn(CPUState *cs, GuestFD *gf) { - return sizeof(featurefile_data); + return gf->staticfile.len; } typedef struct GuestFDFunctions { @@ -759,13 +638,13 @@ static const GuestFDFunctions guestfd_fns[] = { .seekfn = gdb_seekfn, .flenfn = gdb_flenfn, }, - [GuestFDFeatureFile] = { - .closefn = featurefile_closefn, - .writefn = featurefile_writefn, - .readfn = featurefile_readfn, - .isattyfn = featurefile_isattyfn, - .seekfn = featurefile_seekfn, - .flenfn = featurefile_flenfn, + [GuestFDStatic] = { + .closefn = staticfile_closefn, + .writefn = staticfile_writefn, + .readfn = staticfile_readfn, + .isattyfn = staticfile_isattyfn, + .seekfn = staticfile_seekfn, + .flenfn = staticfile_flenfn, }, }; @@ -886,7 +765,8 @@ target_ulong do_common_semihosting(CPUState *cs) errno = EACCES; return set_swi_errno(cs, -1); } - init_featurefile_guestfd(guestfd); + staticfile_guestfd(guestfd, featurefile_data, + sizeof(featurefile_data)); return guestfd; } diff --git a/semihosting/guestfd.c b/semihosting/guestfd.c new file mode 100644 index 0000000000..b6405f5663 --- /dev/null +++ b/semihosting/guestfd.c @@ -0,0 +1,118 @@ +/* + * Hosted file support for semihosting syscalls. + * + * Copyright (c) 2005, 2007 CodeSourcery. + * Copyright (c) 2019 Linaro + * Copyright © 2020 by Keith Packard + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "qemu/osdep.h" +#include "exec/gdbstub.h" +#include "semihosting/guestfd.h" + +static GArray *guestfd_array; + +/* + * Allocate a new guest file descriptor and return it; if we + * couldn't allocate a new fd then return -1. + * This is a fairly simplistic implementation because we don't + * expect that most semihosting guest programs will make very + * heavy use of opening and closing fds. + */ +int alloc_guestfd(void) +{ + guint i; + + if (!guestfd_array) { + /* New entries zero-initialized, i.e. type GuestFDUnused */ + guestfd_array = g_array_new(FALSE, TRUE, sizeof(GuestFD)); + } + + /* SYS_OPEN should return nonzero handle on success. Start guestfd from 1 */ + for (i = 1; i < guestfd_array->len; i++) { + GuestFD *gf = &g_array_index(guestfd_array, GuestFD, i); + + if (gf->type == GuestFDUnused) { + return i; + } + } + + /* All elements already in use: expand the array */ + g_array_set_size(guestfd_array, i + 1); + return i; +} + +/* + * Look up the guestfd in the data structure; return NULL + * for out of bounds, but don't check whether the slot is unused. + * This is used internally by the other guestfd functions. + */ +static GuestFD *do_get_guestfd(int guestfd) +{ + if (!guestfd_array) { + return NULL; + } + + if (guestfd <= 0 || guestfd >= guestfd_array->len) { + return NULL; + } + + return &g_array_index(guestfd_array, GuestFD, guestfd); +} + +/* + * Given a guest file descriptor, get the associated struct. + * If the fd is not valid, return NULL. This is the function + * used by the various semihosting calls to validate a handle + * from the guest. + * Note: calling alloc_guestfd() or dealloc_guestfd() will + * invalidate any GuestFD* obtained by calling this function. + */ +GuestFD *get_guestfd(int guestfd) +{ + GuestFD *gf = do_get_guestfd(guestfd); + + if (!gf || gf->type == GuestFDUnused) { + return NULL; + } + return gf; +} + +/* + * Associate the specified guest fd (which must have been + * allocated via alloc_fd() and not previously used) with + * the specified host/gdb fd. + */ +void associate_guestfd(int guestfd, int hostfd) +{ + GuestFD *gf = do_get_guestfd(guestfd); + + assert(gf); + gf->type = use_gdb_syscalls() ? GuestFDGDB : GuestFDHost; + gf->hostfd = hostfd; +} + +void staticfile_guestfd(int guestfd, const uint8_t *data, size_t len) +{ + GuestFD *gf = do_get_guestfd(guestfd); + + assert(gf); + gf->type = GuestFDStatic; + gf->staticfile.data = data; + gf->staticfile.len = len; + gf->staticfile.off = 0; +} + +/* + * Deallocate the specified guest file descriptor. This doesn't + * close the host fd, it merely undoes the work of alloc_fd(). + */ +void dealloc_guestfd(int guestfd) +{ + GuestFD *gf = do_get_guestfd(guestfd); + + assert(gf); + gf->type = GuestFDUnused; +} diff --git a/semihosting/meson.build b/semihosting/meson.build index 10b3b99921..d2c1c37bfd 100644 --- a/semihosting/meson.build +++ b/semihosting/meson.build @@ -1,3 +1,7 @@ +specific_ss.add(when: 'CONFIG_SEMIHOSTING', if_true: files( + 'guestfd.c', +)) + specific_ss.add(when: ['CONFIG_SEMIHOSTING', 'CONFIG_SOFTMMU'], if_true: files( 'config.c', 'console.c',